[{"content":"First Steps with Thermoptim There are several ways to start working with Thermoptim.\nIn any case, you will need to install the software on your computer, which can be done with the demonstration version. This version allows you to define models, but you will not be able to save them. For that, you need a paid license version.\nA special demo version including the Thermoptim Console with most of the examples from both books and those used in the Guided Explorations has been prepared for you. It\u0026rsquo;s available on the Thermoptim download site.\nOnce Thermoptim is installed, you can use the 45 Guided Explorations, which will allow you to gradually learn how to model many energy systems.\nAs indicated abobe the Thermoptim Console, gives you access to a large number of existing models, including those of the Guided Explorations and most of the examples from the books mentioned on this site.\nFinally, you can use an Example catalog, an older and simplified version of the Console.\nInstallation of Thermoptim Demo Version To use Thermoptim without a paid license, you can install one of the demo versions available at: 🔗 Download Thermoptim\nThermoptim requires the Java Runtime Environment (JRE), preferably version 1.8, to be installed on your machine. If Java is not installed, download it here: 🔗 Download Java\nLaunching Thermoptim To open Thermoptim, double-click the ThoptExec.jar file.\nFor guidance on getting started—such as opening existing project files or using an example catalog—visit this page on the Thermoptim-Unit portal: 🔗 Getting Started with Thermoptim\nGuided Explorations Thermoptim offers about 45 guided model explorations to help you get a handle on the software and introduce you to the modeling of energy systems.\nFor more details, visit: 🔗 Guided Explorations\nInstalling the Thermoptim Console The Thermoptim Console is a dashboard for users of the Thermoptim software.\nIt provides organised access to series of models distributed with the guided explorations or the books: project files, diagram files, exergy structure files, and cycle files. To install the Thermoptim Console, follow these steps:\nDownload the Console archive. Extract it in Thermoptim\u0026rsquo;s installation directory. Double-click file ThermoptimConsole.jar. Then select the type of project that interests you to narrow down the list of those offered to you. Double-click on the one of your choice. Thermoptim is then launched and the project and diagram files are opened.\nThe complete documentation of the Thermoptim Console is available at this address: 🔗 Thermoptim Console\nInstalling an Example Catalog To install an example catalog, follow these steps:\nPlace the catalog folder (containing the proj and schema directories, as well as the text file defining the links to these files) in the Thermoptim installation directory. Edit the loadLib.ini file to include the path to the text file mentioned above. The example catalog will be available the next time you launch Thermoptim, accessible from the Project Files menu.\n","title":"First steps with Thermoptim","uri":"https://server.s4e2.com/crc/tcnpp/resources/first-steps-thopt/"},{"content":"🛠️ Using Exergy Balances in Practice Now that the conceptual foundations are in place, this page shows how exergy balances are actually used — and what precautions to take when interpreting them. Three questions are addressed in turn: how to optimise a cycle step by step, how the choice of source temperature Tk affects the results, and how two reactors with very similar energy efficiencies can have very different exergy profiles.\nU1 — Reading a Balance to Guide Optimisation An energy balance tells you how much energy is lost. An exergy balance tells you where, how much, and in what order to act. This is a fundamental difference for the engineer.\nThe example below follows four successive configurations of a steam cycle based on the AGR design (CO₂ gas coolant, Tk = 700 °C, T₀ = 20 °C). Each configuration was chosen by reading the balance from the previous step.\nThe four configurations The exergy balance files are accessible through the links in this table.\nConfiguration η Xh η energy Dominant irreversibility Simple cycle 53.6 % 37.5 % Source / SG: 73.5 % + Reheat 57.0 % 39.9 % Source / SG: 74.1 % + Reheat + 1 FWH 60.4 % 42.2 % Source / SG: 63.4 % — FWH: 7.4 % + Reheat + 2 FWH 60.7 % 42.4 % Source / SG: 62.3 % — FWH: 8.1 % What is striking is the evolution of the overall exergy efficiency as technological modifications take place.\nStep-by-step reasoning Simple cycle — η Xh = 53.6 %\nThe balance is immediately readable: the source (steam generator) accounts for 73.5 % of total irreversibilities. The economiser alone absorbs 49 %. Turbines represent only 20.7 %, the condenser 5.7 %. The message is unambiguous: the main lever is not in the turbines — it is in the heat transfer from the gas to the steam.\n+ Reheat — η Xh = 57.0 % (+3.4 pts)\nIn a cycle with reheats, we begin by partially expanding the steam, then it passes again into the boiler, where it is heated at the new pressure to approximately the maximum cycle temperature.\nThis results in efficiency gains of a few percent and, most importantly, as shown in the diagram, increased quality at the end of expansion, which is always beneficial for extending the life of turbine blades.\nReheat redistributes some of the SG heat through an additional turbine stage and improves mean isentropic efficiency. Yet the source remains dominant at 74.1 % — its relative weight has barely changed. A different lever is needed.\n+ 1 feedwater extraction (FWH) — η Xh = 60.4 % (+3.4 pts)\nIn a steam cycle, it is possible to undertake partial regeneration by using part of the heat rejected during expansion for preheating the pressurized liquid water before it enters the boiler.\nConsider a cycle with reheat. If we extract a small quantity of steam, called extraction steam or bleed steam, at the outlet of the first expansion, at point 4a in the figure, its pressure remains high enough to condense it at a temperature that allows preheating the pressurized water leaving the pump at point 2.\nThe enthalpy of the vapor is much greater than that of the liquid, due to the latent heat of vaporization. It is then possible to preheat the liquid using a small extraction of steam during expansion.\nThis operation is carried out in specific components called feedwater reheaters FWH.\nThis cycle is called a regenerative Rankine cycle, also known as an extraction and reheat steam cycle.\nNow the source falls to 63.4 % (−10.7 pts). Preheating the feedwater reduces the temperature gap in the economiser, which had been the dominant component since the start. The FWH carries its own irreversibility cost (7.4 %) but saves far more on the source.\n+ 2nd extraction — η Xh = 60.7 % (+0.3 pts only)\nThe source falls slightly again (62.3 %), but the marginal gain collapses. The balance signals that diminishing returns have been reached: the second extraction costs almost as much as it saves.\nSteam extraction allows the feedwater to be preheated (via the FWH) before it enters the economizer. By reducing the temperature difference in the economizer, exergy analysis shows that its irreversibilities have been halved (from 278.5 kW to 129.4 kW).\nThe lesson: at each step, the exergy balance indicated which lever to pull by tracking the dominant component. It serves as a guide for optimization.\nU2 — The Source Temperature Convention: the Choice That Changes Everything All the balances in this section use a source temperature Tk chosen according to the type of heat exchange between the coolant and the steam. The convention is:\nExchange type ΔT Rationale Liquid coolant → boiling (WCR) +35 °C Typical pinch for liquid/boiling exchange Liquid sodium → steam (SFR) +50 °C Larger pinch for liquid/vapour exchange Supercritical water → steam (SCWR) +50 °C Same Gas → steam (AGR, HTR) +60 °C Larger pinch for gas/vapour exchange This convention has a direct consequence: a higher Tk mechanically reduces η Xh, because more of the core irreversibilities are attributed to the source component. Two reactors cannot be compared on η Xh alone without knowing their respective Tk values.\nA concrete illustration — what happens when Tk increases on the Flamanville EPR:\nThe ExergyTkSensitivity tool sweeps Tk from the balance value to 1000 °C, keeping T₀ and all other irreversibilities fixed. Applied to the EPR Flamanville detailed balance (Tk = 334 °C, T₀ = 15 °C):\nSensitivity of η Xh (blue), source % (red) and condenser % (green) to source temperature Tk for the EPR Flamanville detailed model.\nAt Tk = 334 °C (reference): η Xh = 73.4 %, source = 30.0 %, condenser = 22.7 % At Tk ≈ 445 °C: source and condenser curves cross (~30 % each) — the source becomes dominant At Tk = 700 °C: η Xh ≈ 54 %, source ≈ 49 %, condenser ≈ 12 % At Tk = 1000 °C: η Xh ≈ 35 %, source ≈ 57 %, condenser ≈ 9 % The cycle has not changed. Only the accounting of the source has changed. This is why the AGR (Tk = 699 °C, η Xh = 61.8 %) and the EPR (Tk = 334 °C, η Xh = 73.9 %) cannot be compared directly: the AGR balance includes the irreversibilities of the entire CO₂ coolant circuit, while the EPR balance only includes the near-boiling heat exchange at 334 °C.\nThe crossing point at ~445 °C is particularly informative: below this temperature, the condenser is the larger structural loss term; above it, the source dominates.\nThe physical basis: Carnot factors and what Tk really controls\nThe source temperature Tk enters the exergy balance through the Carnot factor (1 − T₀/Tk), which converts a heat flow Q into its exergy equivalent:\nXh = Q × (1 − T₀/Tk)\nChanging Tk therefore changes the exergy attributed to a heat exchange — and this has very different consequences depending on whether it is the hot source or the cold source that is varied.\nVarying the hot source temperature Tk affects only the components that exchange heat with the hot source — typically the steam generator, economiser, core, or IHX. All other irreversibilities in the balance (turbines, feedwater heaters, mixing valves, pumps) are computed from fluid state differences and do not depend on Tk. This is exactly what the ExergyTkSensitivity tool exploits: it sweeps Tk over a range and recomputes only the source component contributions, keeping everything else fixed. The result is a clean sensitivity curve that answers the question \u0026ldquo;how much of the η Xh difference between two reactors is due to the Tk convention?\u0026rdquo;\nIt is precisely because the thermal power Q transferred by the hot source can be back-calculated from the source exergy and Tk — via Q = Xh_source / (1 − T₀/Tk) — that the values Q_th and η energy have been appended to the bottom of the exergy balance files. Knowing Q_th allows the energy efficiency to be derived directly from the balance, without requiring a separate energy model. The ExerBalanceHX post-processing tool computes and writes these two values automatically when it processes a balance.\nVarying the cold source temperature Tcond is an entirely different matter. Tcond is the temperature of the condenser cooling fluid. If it changes, the condenser thermal equilibrium shifts, its condensation pressure changes, and — through the turbine expansion ratios — the pressures and enthalpies at every turbine stage are modified. The irreversibilities of all turbine stages change, the extraction flows to the feedwater heaters change, and the entire cycle operates at a new off-design point. This cannot be studied by a simple balance recalculation: it requires a full thermodynamic cycle model operating at the new conditions.\nThis is one of the specific strengths of Nuscle: because it models the complete secondary circuit thermodynamically, it can simulate the effect of a change in condensation temperature and generate a new consistent exergy balance for the modified operating point — something that a post-processing tool like ExergyTkSensitivity cannot do. The NuScale US460 and ABWR cases (both designed with air-cooled condensers at 35 °C rather than the standard 15 °C) will be studied this way when the corresponding Nuscle parametric models are available.\nTwo valid questions, two valid conventions:\n\u0026ldquo;How good is the secondary cycle alone?\u0026rdquo; → Use a Tk close to the actual heat exchange temperature (Tprimary + ΔT). Differences between reactors reflect cycle quality. \u0026ldquo;How efficiently does the full plant convert nuclear heat?\u0026rdquo; → Use a common Tk for all reactors. Differences reflect the combination of core and cycle performance. Both are legitimate. The key is to state which question is being answered before presenting the numbers.\nU3 — Exergy Balances as a Diagnostic Instrument The AGR four-step example in U1 illustrates a general principle: as a cycle approaches its thermodynamic optimum, the dominant irreversibility shifts from the source to the components that are harder to reduce.\nThe EPR Flamanville 3 is a 1 650 MWe pressurised water reactor, primary at 300 °C / 155 bar, steam at 294 °C / 75 bar, with eight feedwater heaters, double reheat, and six LP turbine stages. It is the most powerful reactor currently operating in France.\nFor the EPR Flamanville detailed model (η Xh = 73.9 %), the exergy balance shows:\nComponent % of total irreversibilities Source (SG + economiser) 30.0 % Turbines 32.2 % Condenser 22.7 % Feedwater heaters (FWH) 0.7 % Reheaters 3.8 % Remaining 10.6 % No single component dominates. The balance is well distributed — a signature of a well-optimised cycle. Any further improvement would require acting on multiple components simultaneously for marginal gains.\nThe VVER-70 is the first Soviet pressurised water reactor design, installed at the Novovoronezh plant (units 1–2, 1964–1969). Three K-70-29 turbines of 70 MWe each give a total output of 210 MWe from a thermal power of 760 MWth. The primary coolant operates at approximately 248 °C, steam is produced at 29 bar — saturated, with no superheat. Between the HP and LP turbine sections, a moisture separator reduces liquid content to ~1 % but does not raise steam temperature.\nFor the VVER-70 (η Xh = 57.5 %, Nuscle model), the exergy balance shows:\nComponent % Source 39.5 % Turbines 36.6 % Condenser 19.2 % FWH 1.6 % Here the source is clearly dominant (39.5 %) and the FWH contribution is almost negligible (1.6 %). The balance immediately points to two actions: reduce the temperature gap in the steam generator (e.g., by adding superheat) and increase the regenerative feedwater heating. These are precisely the changes made in the VVER-1000, which achieves η Xh = 68.0 % — a gain of 10.5 points.\nTwo modelling notes for the VVER-70 are important for correct interpretation:\nNo reheat after the separator. The K-70-29 turbine uses a moisture separator only — there is no steam reheater between the HP and LP sections. The separator reduces liquid content to approximately 1 %, but without raising the steam temperature. The Nuscle model reflects this by setting the reheat flow to effectively zero; the corresponding lines have been removed from the published balance. This means the VVER-70 and VVER-1000 are not simply two generations of the same design — they represent two fundamentally different cycle philosophies (saturated steam + separator vs superheated steam + MSR).\nTalim is estimated. The feedwater inlet temperature to the steam generator (Talim) is not documented in available sources for the Novovoronezh unit 1-2. It has been estimated from the known thermal power (760 MWth) and electrical output (210 MWe). A ±20 °C uncertainty on Talim propagates to approximately ±3 pts on the source % and FWH % individually, but affects η Xh global by less than ±0.5 pt. The η Xh = 57.5 % figure is therefore robust; the component breakdown carries a moderate uncertainty on the source/FWH split.\nThe exergy balance is a diagnostic instrument. It does not prescribe solutions, but it ranks the components by their contribution to total irreversibility — and that ranking is the starting point for any systematic optimisation effort.\nU4 — η Xh and η Energy: Two Readings of the Same Cycle η Xh and η energy (= net electrical output / thermal power input Q_th) are two important indicators. This is why we have included both in all balances.\nHere are some results:\nReactor Tk (°C) η Xh η energy Ratio η Xh / η energy EPR Flamanville (detailed) 334 73.9 % 38.5 % 1.92 Canadian SCWR 670 68.5 % 47.6 % 1.44 AGR Hartlepool 699 61.8 % 43.5 % 1.42 Superphénix 600 64.7 % 43.3 % 1.49 CANDU 292 68.4 % 33.5 % 2.04 RBMK 324 65.2 % 33.7 % 1.93 HTR-PM 624 59.2 % — — The ratio η Xh / η energy is roughly constant (~1.9–2.0) for WCR designs with Tk near 300–340 °C, but falls significantly for high-temperature reactors (SCWR: 1.44, AGR: 1.42). This reflects the fact that at high Tk, the source Carnot factor (1 − T₀/Tk) is large — the exergy of the heat supplied approaches its energy value — so η Xh and η energy converge.\nFor low-Tk WCR designs, Q_th must be much larger than the electrical output to provide the same exergy resource, so η Xh appears much higher than η energy. This is thermodynamically consistent: the available work fraction of heat at 300 °C is only ~50 %, meaning the reactor must supply roughly twice the exergy to produce a given electrical output.\nPractical implication: η energy is the efficiency most familiar to plant operators and regulators. η Xh is the efficiency most useful for cycle optimisation and inter-design comparison. Neither is \u0026ldquo;more correct\u0026rdquo; — they answer different questions.\nU5 — Exergy Diagrams: Visualising Irreversibility Numbers in a table tell the story. Diagrams make it immediately visible. Three complementary representations are used in this section.\nThe Grassmann / exergy Sankey diagram The Grassmann diagram is the exergy counterpart of the Sankey energy flow diagram. Each arrow is proportional to the exergy flow it represents. Irreversibilities appear as arrows branching off to the side — they literally show exergy \u0026ldquo;leaking out\u0026rdquo; of the system at each component.\nFor the four AGR configurations (U1), a Grassmann diagram shows the economizer branch shrinking between configurations 1 and 3 as the FWH reduces the temperature gap — while a new branch appears for the FWH itself. The net reduction in total branch width is the gain in η Xh.\nThe Grassmann diagram is most readable for simple cycles (4–8 components). For complex cycles like the EPR (40+ components), it becomes dense; the stacked bar chart is then more practical.\nGrassmann diagrams for the AGR configurations will be added here when available.\nStacked bar charts of irreversibility distribution This is the representation used in U1. Each bar shows the percentage distribution of irreversibilities across component groups (source, turbines, condenser, FWH, reheaters) for one configuration. Overlaying the η Xh curve on a second axis makes the link between component-level changes and global efficiency immediately visible.\nThe stacked bar chart is the most practical format for comparing multiple configurations or multiple reactors, because it is compact, easy to read, and directly generated from the balance data. It answers the question \u0026ldquo;where do the losses go?\u0026rdquo; at a glance.\n*Evolution of irreversibility distribution across four AGR cycle configurations. The source (green) dominates until feedwater heating is introduced (step 3). The marginal gain from the second extraction (step 4) is immediately visible.* Sensitivity curves (ExergyTkSensitivity) The ExergyTkSensitivity is a tool that accepts any Thermoptim exergy balance (pasted into a text area), and sweeps Tk from the balance value to 1000 °C, and plots three quantities in real time: η Xh, source %, and condenser %. An Export CSV button allows the data to be retrieved for further processing.\nThe tool is distributed as a standalone JAR and accepts both the modern RAW_FORMAT (UTF-8, dot decimal) and legacy locale-formatted balances.\nA JAR or Java Archive is a software package that bundles all the compiled Java class files, resources and metadata needed to run an application into a single compressed file. Like a ZIP archive, it can be opened and inspected with any standard archive tool. To run it, the user only needs a Java Runtime Environment (JRE) installed on their machine — no installation, no dependencies to manage. A double-click or the command java -jar filename.jar is sufficient.\nThe ExergyTkSensitivity tool applied to the EPR Flamanville detailed balance. η Xh (blue) falls from 73.4 % at Tk = 334 °C to ~35 % at 1000 °C. Source % (red) rises from 30 % to ~57 %. Condenser % (green) falls from 22.7 % to ~9 %. The source and condenser curves cross at ~445 °C.\nThis diagram answers a specific question: how much of the apparent η Xh difference between two reactor types is due to the Tk convention, and how much reflects genuine cycle quality? Sweeping Tk from 334 °C (EPR convention) to 699 °C (AGR convention) shows η Xh falling from 73.4 % to approximately 54 % — entirely due to the change in accounting, with no change to the cycle itself.\nFor the NuScale US460 and ABWR, which use a condenser at 35 °C (air-cooled design basis), the sensitivity to Tcond will be demonstrated when the corresponding Nuscle parametric models are available.\nU6 — The Five Pillars of Exergy Analysis In U1, we used exergy balances to optimise an AGR cycle. But optimisation is only the entry point. Beyond it, exergy analysis opens five fundamental pillars where it provides something no other method can.\n1. Advanced Diagnostics and Physical Analysis Exergy acts as a \u0026ldquo;medical scanner\u0026rdquo; for industrial processes, making \u0026ldquo;invisible\u0026rdquo; losses visible.\nAnomaly Detection: It identifies components with disproportionate irreversibilities, such as a feedwater heater with low isentropic efficiency or a turbine struggling with wet steam conditions, which would remain hidden in a standard energy analysis.\nInternal vs. External Losses: It distinguishes between exergy rejected to the environment (exhaust) and exergy destroyed internally due to friction, chemical reactions, or heat transfer across large temperature gaps.\n2. Universal Benchmarking and Technology Comparison Exergy provides a \u0026ldquo;unique currency\u0026rdquo; that enables rigorous comparison of disparate energy flows and systems.\nHeterogeneous Systems: It allows designers to compare the efficiency of a biomass boiler with an electric heat pump or a solar thermal system on equal footing.\nArchitectural Benchmarking: It facilitates the comparison of different reactor architectures (e.g., VVER-70 vs. VVER-1000) or low-carbon technologies (e.g., nuclear vs. combined-cycle gas turbines) by using consistent reference temperatures ((T_k)).\n3. Strategic Design and \u0026ldquo;Blank Page\u0026rdquo; Engineering In the early stages of design, exergy balances guide the choice of system architecture before detailed engineering begins.\nIdentifying Leverage Points: Simplified models can immediately reveal if a design is \u0026ldquo;source-dominated\u0026rdquo; or \u0026ldquo;turbine-dominated\u0026rdquo;, indicating whether the designer should focus on upstream primary temperatures or downstream turbine efficiency.\nSystems Integration: It forms the foundation of Pinch Analysis, helping to identify optimal couplings between processes—such as using 200°C waste heat as a resource for a process requiring 150°C—to create coherent multi-energy networks.\n4. Sustainability and Environmental Impact Exergy is a primary indicator of resource depletion and true environmental efficiency.\nSustainability Metrics: It measures what is irreversibly lost versus what could potentially be recovered, such as identifying the cogeneration potential of waste heat rejected by a condenser.\nExergy-Based Life Cycle Assessment (ELCA): It serves as the basis for Exergy-Based Life Cycle Assessments (ELCA), quantifying the exergy footprint of industrial processes and the degradation of raw materials.\n5. Economic Valuation and Policy Governance Because exergy is correlated with the economic value of an energy flow, it serves as a tool for strategic decision-making.\nInvestment Prioritization: Higher exergy flows (like electricity) command higher economic value than low-exergy flows (low-temperature heat), allowing factories to establish internal pricing and prioritize investments.\nTechnological Arbitrage: It provides a scientific basis for policy decisions, such as demonstrating why using hydrogen for domestic heating is a \u0026ldquo;strategic heresy\u0026rdquo; due to exergy destruction, whereas its use in heavy industry is justified.\nPedagogical Tool: It clarifies the fundamental difference between energy quantity and quality, helping to explain the structure of losses in any complex system.\nU7 — Nuscle Models vs Detailed Models: What the Gap Means When the same reactor is modelled with both Nuscle and a full Thermoptim model, the η Xh values differ systematically — by 6 to 8 points for WCR designs. This is not a flaw; it is a known and quantifiable property of the simplified model.\nEPR Flamanville — two models, same reactor:\nModel η Xh η energy Source % Condenser % Turbines % Detailed 73.9 % 38.5 % 30.0 % 22.7 % 32.2 % Nuscle 65.8 % 34.6 % 22.7 % 18.6 % 39.5 % Gap −8.1 pts −3.9 pts −7.3 pts −4.1 pts +7.3 pts The Nuscle model uses fewer feedwater heaters and larger extractions to reach the same feedwater temperature. This pushes more of the work through the turbines (hence the higher turbine percentage) and reduces the apparent source and condenser contributions. The η Xh is lower not because the reactor is worse, but because the cycle model is simplified.\nWhy this matters for comparisons: when comparing a Nuscle model with a detailed model, the gap is real but not a direct measure of reactor quality. The Nuscle result tells you where the cycle sits relative to other WCR designs modelled the same way. The detailed result gives the absolute reference.\nNuscle is best understood as a rapid prototyping and pedagogical tool — it answers \u0026ldquo;how does this WCR design compare to others under the same modelling assumptions?\u0026rdquo; rather than \u0026ldquo;what is the exact η Xh of this reactor?\u0026rdquo;\nThis page corresponds to posts U1 through U7 of the companion LinkedIn series on exergy analysis of nuclear reactor thermodynamic cycles.\n","title":"Using Exergy Balances","uri":"https://server.s4e2.com/crc/tcnpp/resources/exergy/usage/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\nAppendix 1 – Reminders A1.1 Thermodynamic Property Diagrams of Pure Substances A1.2 Calculation of Heat Exchangers by the NTU Method A1.3 Conclusion A1.4 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/appendix1/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\nAppendix 2 – Turbines A2.1 Steam Turbines A2.2 Gas Turbines A2.3 Conclusion A2.4 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/appendix2/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n1. Presentation of the Approach 1.1 A Two-Level Methodology 1.1.1 Physical Phenomena Taking Place in a Gas Turbine 1.1.2 Energy Technologies: Component Assemblies 1.2 Practical Implementation of the Double Analytical–Systems Approach 1.2.1 Use of the Thermoptim Software 1.2.2 Functional and Exergy Structures 1.3 Thermoptim Primitive Types 1.3.1 Component Modeling 1.3.2 Thermoptim Primitive Types 1.3.3 Thermoptim Assets 1.4 Conclusion 1.5 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter1/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n2. Physical Phenomena Involved in Nuclear Reactors, Panorama of Nuclear Reactors 2.1 Physical Phenomena Involved in Nuclear Reactors 2.1.1 Structure of an Atom 2.1.2 Fission of Uranium 2.1.3 Operating Principles of Nuclear Reactors with Uranium Fission 2.1.4 Conclusion 2.2 Overview of Nuclear Fission Reactors 2.2.1 Introduction 2.2.2 Generations of Nuclear Reactors 2.2.3 Reactor Containment 2.2.4 Pressurized Water Reactors (PWRs) 2.2.5 VVER Reactors 2.2.6 Boiling Water Reactors (BWRs) 2.2.7 RBMK Reactors 2.2.8 Supercritical Water-Cooled Reactors (SCWRs) 2.2.9 Advanced Gas-Cooled Reactors (AGRs) 2.2.10 Pressurized Heavy Water Reactors (PHWRs) or CANDUs 2.2.11 Sodium-Cooled Fast Reactors (SFRs) 2.2.12 Fast Neutron Reactors (FNRs) 2.2.13 Lead-Cooled Fast Reactors (LFRs) 2.2.14 High Temperature Reactors (HTRs) 2.2.15 Very High Temperature Reactors (VHTRs) 2.2.16 Molten Salt Reactors (MSRs) 2.2.17 Fast Molten Salt Reactors (FMSRs) 2.2.18 Relative Sizes of Reactors 2.2.19 Summary 2.2.20 Mind Maps 2.3 Conclusion 2.4 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter2/toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n3. Steam and Gas Power Cycles: Understanding, Analysis, and Improvement Methodologies 3.1 Introduction to Steam and Gas Power Cycles 3.1.1 Conversion of Heat into Work 3.1.2 Carnot Cycle 3.2 Steam Power Plant and Gas Turbine Cycles 3.2.1 Simple Steam Power Plant 3.2.2 Simple Closed Gas Turbine Cycle 3.3 Comparison with the Carnot Cycle in the Entropy Diagram 3.3.1 Steam Power Plant 3.3.2 Gas Turbine 3.4 Methodological Tools for Analysis and Improvement 3.4.1 Introduction to Thermoptim 3.4.2 Thermoptim Model of the Steam Cycle 3.4.3 Thermoptim Model of the Gas Turbine Cycle 3.4.4 Exergy Balances, Exergy Structures 3.4.5 Process Integration by the Pinch Method 3.5 Conclusion 3.6 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter3/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n4. Improvement of Steam Power Cycles 4.1 High-Temperature Steam Power Cycles 4.1.1 Basic Hirn or Rankine Cycle with Superheat 4.1.2 Exergy Balance 4.1.3 Thermodynamic Limits of the Simple Hirn Cycle 4.1.4 Cycle with Reheat 4.1.5 Cycle with Extraction 4.1.6 Technical Constraints in AGRs 4.1.7 SFR, FNR, HTR-PM, MSR, FMSR Cycles 4.2 Supercritical Cycles 4.3 Conclusion 4.4 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter4/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n5. Medium Temperature Steam Power Cycles 5.1 Main Categories of Water-Cooled Nuclear Reactors 5.2 Architecture of PWRs 5.3 Architecture of BWRs 5.4 Architecture of RBMK Reactors 5.5 Architecture of CANDU Reactors 5.6 Implications for the Secondary Circuit 5.7 Moisture Separator Reheater 5.8 Expansion in the Wet Steam Region 5.8.1 Reduced Polytropic Efficiency 5.8.2 Increased Mechanical and Chemical Stress on Turbine Blades 5.8.3 Condensate Removal in Turbines 5.8.4 Suboptimal Flow Rates for Feedwater Heating 5.9 Secondary Circuits of Water-Cooled Reactors 5.9.1 Naval Propulsion 5.9.2 Thermodynamic Cycles of Electricity Generation WCRs 5.10 ORC Power Plants 5.11 Binary Cycles 5.12 Conclusion 5.13 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter5/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n6. Improvement of Closed Cycle Gas Turbines 6.1 Energy and Exergy Balances of the Simple Cycle 6.1.1 Energy and Exergy Balances of the Simple Cycle 6.1.2 Cycle Improvements 6.2 Supercritical CO₂ Cycles 6.2.1 Characteristics of sCO₂ Cycles 6.2.2 Simple Regeneration Cycle 6.2.3 Pre-Compression Cycle 6.2.4 Recompression Cycle 6.2.5 Partial Cooling Cycle 6.2.6 Conclusion 6.3 Technology Readiness Level of Gas Cycles 6.3.1 TRL of Turbomachinery 6.3.2 TRL of High-Temperature Reactors 6.4 Conclusion 6.5 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter6/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n7. Specific Applications and Perspectives: Combined Cycles, Desalination, Hydrogen Production, Cogeneration 7.1 Combined Cycles 7.1.1 General Overview 7.1.2 Single Pressure Combined Cycle 7.1.3 Dual Pressure Level Combined Cycle 7.1.4 Supercritical CO₂ Combined Cycle 7.1.5 Kalina Cycle 7.2 Desalination of Seawater 7.2.1 Boiling Point Elevation 7.2.3 Single Effect Distillation 7.2.4 Multiple Effect Distillation 7.2.5 Multi-Stage Flash Desalination Cycle 7.2.6 Reverse Osmosis Desalination 7.2.7 Mechanical Vapor Compression 7.3 Hydrogen Production, Methane Reforming, Electrolysis 7.3.1 Hydrogen Production Processes 7.3.2 Reforming 7.3.3 Electrolysers 7.4 Cogeneration or Combined Heat and Power (CHP) 7.4.1 Performance Indicators 7.4.2 Boilers and Steam Turbines 7.4.3 Nuclear Cogeneration 7.5 Conclusion 7.6 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter7/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n8. Case Studies 8.1 Detailed Model of the AGR 650 MW NPP 8.2 Detailed Model of the NUSCALE 50 MW NPP 8.3 Detailed Model of the NUSCALE 77 MW NPP 8.4 Detailed Model of the ABWR 1350 MW NPP 8.5 Detailed Model of the RBMK 1000 MW NPP 8.6 Detailed Model of the VVER 1000 MW NPP 8.7 Detailed Model of the CANDU 550 MW NPP 8.8 Detailed Model of the Superphenix 1175 MW NPP 8.9 Detailed Model of the HTR-PM 67 MW NPP 8.10 Detailed Model of the Canadian SCWR 1250 MW NPP 8.11 Flamanville 3 EPR Steam Generator Model 8.12 Conclusion ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter8/_toc/"},{"content":"Table of Contents — Volume 2 Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants\n9. Systemic Modeling: A Strategic Imperative for Energy Engineering Education Introduction 9.1 Strategic Value of Thermodynamic Expertise 9.2 An Enduring Professional Asset ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter9/_toc/"},{"content":"Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants Introduction A Unique Work An Industrial and Strategic Challenge Pedagogical and Methodological Context Systemic and Analytical Modeling Supported by Powerful Methodological Tools Technology Readiness Level Content of the Book Conclusion References 1. Systems Approach and Innovative Teaching of Thermodynamic Cycles of Nuclear Power Plants with Thermoptim 1.1 Analysis of Energy Systems 1.1.1 Introduction to Energy Systems 1.1.2 Illustration: The Steam Power Plant 1.1.3 Functional Structure and Diagram of the Steam Power Plant 1.1.4 Exergy Structure and Diagram of the Steam Power Plant 1.1.5 Complementarity and Duality of Structures 1.2 A New Pedagogical Paradigm for Thermodynamic Cycles of Nuclear Power Plants 1.2.1 Context and Pedagogical Challenges 1.2.2 Limits of Classical Cycle Teaching 1.2.3 An Innovative Pedagogical Approach 1.2.4 A Pedagogy Adapted to Different Audiences 1.2.5 CFRP Approach: An Inductive Progression 1.2.6 Which Equations to Teach? 1.2.7 Comparison with the Anglo-Saxon Approach 1.2.8 Example: Modeling a Steam Turbine 1.3 Thermoptim, a Tool for Modeling and Teaching TCNPPs 1.3.1 Presentation of Thermoptim 1.3.2 Pedagogical Advantages of Thermoptim 1.3.3 Getting Started with Thermoptim 1.4 Conclusion 1.5 References 2. Physical Phenomena Involved in Nuclear Reactors, Panorama of Nuclear Reactors 2.1 Physical Phenomena Involved in Nuclear Reactors 2.1.1 Structure of an Atom 2.1.2 Fission of Uranium 2.1.3 Operating Principles of Nuclear Reactors with Uranium Fission 2.1.4 Conclusion 2.2 Overview of Nuclear Fission Reactors 2.2.1 Introduction 2.2.2 Generations of Nuclear Reactors 2.2.3 Reactor Containment 2.2.4 Pressurized Water Reactors (PWRs) 2.2.5 VVER Reactors 2.2.6 Boiling Water Reactors (BWRs) 2.2.7 RBMK Reactors 2.2.8 Supercritical Water-Cooled Reactors (SCWRs) 2.2.9 Advanced Gas-Cooled Reactors (AGRs) 2.2.10 Pressurized Heavy Water Reactors (PHWRs) or CANDUs 2.2.11 Sodium-Cooled Fast Reactors (SFRs) 2.2.12 Fast Neutron Reactors (FNRs) 2.2.13 Lead-Cooled Fast Reactors (LFRs) 2.2.14 High Temperature Reactors (HTRs) 2.2.15 Very High Temperature Reactors (VHTRs) 2.2.16 Molten Salt Reactors (MSRs) 2.2.17 Fast Molten Salt Reactors (FMSRs) 2.2.18 Relative Sizes of Reactors 2.2.19 Summary 2.2.20 Mind Maps 2.3 Conclusion 2.4 References 3. Steam and Gas Power Cycles: Understanding, Analysis, and Improvement Methodologies 3.1 Introduction to Steam and Gas Power Cycles 3.1.1 Conversion of Heat into Work 3.1.2 Carnot Cycle 3.2 Steam Power Plant and Gas Turbine Cycles 3.2.1 Simple Steam Power Plant 3.2.2 Simple Closed Gas Turbine Cycle 3.3 Comparison with the Carnot Cycle in the Entropy Diagram 3.3.1 Steam Power Plant 3.3.2 Gas Turbine 3.4 Methodological Tools for Analysis and Improvement 3.4.1 Introduction to Thermoptim 3.4.2 Thermoptim Model of the Steam Cycle 3.4.3 Thermoptim Model of the Gas Turbine Cycle 3.4.4 Exergy Balances, Exergy Structures 3.4.5 Process Integration by the Pinch Method 3.5 Conclusion 3.6 References 4. Improvement of Steam Power Cycles 4.1 High-Temperature Steam Power Cycles 4.1.1 Basic Hirn or Rankine Cycle with Superheat 4.1.2 Exergy Balance 4.1.3 Thermodynamic Limits of the Simple Hirn Cycle 4.1.4 Cycle with Reheat 4.1.5 Cycle with Extraction 4.1.6 Technical Constraints in AGRs 4.1.7 SFR, FNR, HTR-PM, MSR, FMSR Cycles 4.2 Supercritical Cycles 4.3 Conclusion 4.4 References 5. Medium Temperature Steam Power Cycles 5.1 Main Categories of Water-Cooled Nuclear Reactors 5.2 Architecture of PWRs 5.3 Architecture of BWRs 5.4 Architecture of RBMK Reactors 5.5 Architecture of CANDU Reactors 5.6 Implications for the Secondary Circuit 5.7 Moisture Separator Reheater 5.8 Expansion in the Wet Steam Region 5.8.1 Reduced Polytropic Efficiency 5.8.2 Increased Mechanical and Chemical Stress on Turbine Blades 5.8.3 Condensate Removal in Turbines 5.8.4 Suboptimal Flow Rates for Feedwater Heating 5.9 Secondary Circuits of Water-Cooled Reactors 5.9.1 Naval Propulsion 5.9.2 Thermodynamic Cycles of Electricity Generation WCRs 5.10 ORC Power Plants 5.11 Binary Cycles 5.12 Conclusion 5.13 References 6. Improvement of Closed Cycle Gas Turbines 6.1 Energy and Exergy Balances of the Simple Cycle 6.1.1 Energy and Exergy Balances of the Simple Cycle 6.1.2 Cycle Improvements 6.2 Supercritical CO₂ Cycles 6.2.1 Characteristics of sCO₂ Cycles 6.2.2 Simple Regeneration Cycle 6.2.3 Pre-Compression Cycle 6.2.4 Recompression Cycle 6.2.5 Partial Cooling Cycle 6.2.6 Conclusion 6.3 Technology Readiness Level of Gas Cycles 6.3.1 TRL of Turbomachinery 6.3.2 TRL of High-Temperature Reactors 6.4 Conclusion 6.5 References 7. Specific Applications and Perspectives: Combined Cycles, Desalination, Hydrogen Production, Cogeneration 7.1 Combined Cycles 7.1.1 General Overview 7.1.2 Single Pressure Combined Cycle 7.1.3 Dual Pressure Level Combined Cycle 7.1.4 Supercritical CO₂ Combined Cycle 7.1.5 Kalina Cycle 7.2 Desalination of Seawater 7.2.1 Boiling Point Elevation 7.2.3 Single Effect Distillation 7.2.4 Multiple Effect Distillation 7.2.5 Multi-Stage Flash Desalination Cycle 7.2.6 Reverse Osmosis Desalination 7.2.7 Mechanical Vapor Compression 7.3 Hydrogen Production, Methane Reforming, Electrolysis 7.3.1 Hydrogen Production Processes 7.3.2 Reforming 7.3.3 Electrolysers 7.4 Cogeneration or Combined Heat and Power (CHP) 7.4.1 Performance Indicators 7.4.2 Boilers and Steam Turbines 7.4.3 Nuclear Cogeneration 7.5 Conclusion 7.6 References 8. Case Studies 8.1 Detailed Model of the AGR 650 MW NPP 8.2 Detailed Model of the NUSCALE 50 MW NPP 8.3 Detailed Model of the NUSCALE 77 MW NPP 8.4 Detailed Model of the ABWR 1350 MW NPP 8.5 Detailed Model of the RBMK 1000 MW NPP 8.6 Detailed Model of the VVER 1000 MW NPP 8.7 Detailed Model of the CANDU 550 MW NPP 8.8 Detailed Model of the Superphenix 1175 MW NPP 8.9 Detailed Model of the HTR-PM 67 MW NPP 8.10 Detailed Model of the Canadian SCWR 1250 MW NPP 8.11 Flamanville 3 EPR Steam Generator Model 8.12 Conclusion 9. Systemic Modeling: A Strategic Imperative for Energy Engineering Education Introduction 9.1 Strategic Value of Thermodynamic Expertise 9.2 An Enduring Professional Asset Appendices Appendix 1 – Reminders A1.1 Thermodynamic Property Diagrams of Pure Substances A1.2 Calculation of Heat Exchangers by the NTU Method A1.3 Conclusion A1.4 References Appendix 2 – Turbines A2.1 Steam Turbines A2.2 Gas Turbines A2.3 Conclusion A2.4 References ","title":"Table of Contents","uri":"https://server.s4e2.com/crc/tcnpp/_toc/"},{"content":"🔬 Detailed Models — Component-by-Component Analysis This page presents the exergy balances of all reactors modelled with full Thermoptim detail. All balances were generated using Thermoptim exergy structures and processed with ExerBalanceHX. The thermal power Q_th and energy efficiency η energy are computed from the source components as:\nQ_th = Σ Xh_resource / (1 − T₀/Tk) η energy = W_net / Q_th\nT₀ = 15 °C for all balances. Several reactors use a condensation temperature different from 15 °C — this is noted in the table and discussed in each section.\nThis page complements the one that presents the datasheets by reactors and provides access to their flowsheets.\nThis chart summarises at a glance the diversity of the 12 cycles analysed — from low-temperature WCR designs to gas-cooled and supercritical reactors, via sodium and helium cycles. Each polygon is a thermodynamic signature. Hover over a name in the legend to isolate a cycle.\nSummary Table Reactor Tk (°C) Tc (°C) η Xh η energy Source % Cond % Turbines % FWH % EPR Flamanville 3 334 15 73.4 % 38.5 % 30.0 % 22.7 % 32.8 % 1.5 % ABWR 330 35* 72.4 % 37.8 % 31.2 % 18.6 % 33.5 % 7.9 % CANDU Pickering 292 15 68.4 % 33.5 % 24.1 % 25.7 % 34.1 % 3.2 % NuScale US600 339 31* 67.6 % 35.8 % 56.6 % 12.8 % 25.9 % 4.6 % VVER-1000 313 15 65.9 % 33.5 % 19.7 % 17.8 % 46.8 % 9.3 % RBMK-1000 324 15 65.2 % 33.7 % 30.1 % 17.0 % 38.2 % 7.1 % Superphénix 600 15 64.7 % 43.3 % 25.6 % 16.0 % 16.0 % 3.2 % AGR Hartlepool 699 15 61.8 % 43.5 % 37.3 % 9.7 % 18.1 % 3.5 % HTR-PM 800 15 58.6 % 41.7 % 40.0 %† 8.6 % 13.6 % 8.3 % NuScale US460 (77 MWe) 318 28* 59.8 % 30.7 % 36.1 % 9.8 % 38.9 % 2.8 % VVER-70 283 15 57.5 % 27.7 % 39.5 % 19.2 % 36.6 % 1.6 %‡ * Air-cooled condenser (ABWR, NuScale US460) or model-specific condensation temperature (NuScale US600: Tc = 31 °C). † HTR-PM source % = reactor core only (43.5 %). The steam generator He→steam (20.6 %) is modelled as an internal exchanger without Tk annotation. Core + SG = 64.1 %. ‡ VVER-70 FWH %: estimated — feedwater temperature Talim not documented; see modelling note below.\nThis parallel coordinates chart traces in a single view the 12 cycles analysed. Each polyline is a second thermodynamic signature: where lines cross between two axes, reactors swap their ranking on that criterion. Hover over a name in the legend to isolate a cycle.\nAGR Hartlepool — Tk = 699 °C η Xh = 61.8 %, η energy = 43.5 %. CO₂ gas-cooled, four-section SG. Steam at 541 °C / 170 bar.\nComponent group % Reactor core (Tk = 699 °C) 37.3 % SG economiser 11.1 % SG evaporator 6.7 % SG reheater 6.0 % SG superheater 6.9 % SG total 30.7 % Condenser 9.7 % Turbines 18.1 % FWH 1–4 3.5 % The condenser (9.7 %) is the lowest in the corpus — direct benefit of the high steam temperature. FWH1 has an exergy efficiency of 52.7 %, the least efficient heater in the corpus, operating over the largest temperature difference.\n📐 Exergy Balance Hartlepool NuScale US600 (50 MWe) — Tk = 339 °C, Tc = 31 °C η Xh = 67.6 %, η energy = 35.8 %. Integral PWR, natural circulation, 300 °C / 34 bar, three feedwater heaters. Tc = 31 °C is the model-specific condensation temperature.\nComponent group % Steam generator (Tk = 339 °C) 56.6 % Turbines (7 stages) 25.9 % Condenser (Tc = 31 °C) 12.8 % FWH (LP2, LP3, HP4) 4.6 % The steam generator dominates at 56.6 % — the structural cost of a low-temperature natural-circulation design at 300 °C. Three FWH stages limit regenerative complexity.\n📐 Exergy Balance NuScale US600 (50 MWe) --- NuScale US460 (77 MWe) — Tk = 318 °C, Tc = 28 °C η Xh = 59.8 %, η energy = 30.7 %. Integral PWR, natural circulation, 300 °C / 34 bar, three feedwater heaters. Tc = 28 °C is the actual condensation temperature of the model (0.038 bar). Air-cooled condenser design basis per NRC SDAA.\nComponent group % Steam generator (Tk = 318 °C) 36.1 % Turbines (4 stages) 38.9 % Condenser (Tc = 28 °C) 9.8 % FWH (FWH1–3) 2.8 % Turbine 4 alone carries 15.7 % of total irreversibilities, with a polytropic efficiency of 60.5 % — physically correct for wet steam (quality 0.885) at 0.581 bar expanding at a pressure ratio of 8.3 to a condenser at 0.038 bar.\n📐 Exergy Balance NuScale US460 (77 MWe) ABWR — Tk = 330 °C, Tc = 35 °C η Xh = 72.4 %, η energy = 37.8 %. Direct-cycle BWR: steam generated directly in the core, no steam generator. The condensation temperature of 35 °C reflects the air-cooled condenser design basis per NRC SDAA.\nComponent group % Source (Tk = 330 °C) 31.2 % Turbines 33.5 % Condenser (Tc = 35 °C) 18.6 % FWH (LP1–LP4, HP5, HP6) 7.9 % Reheater (net) 4.3 % The direct-cycle architecture eliminates steam generator irreversibilities. The source (31.2 %) is comparable to the EPR despite a simpler secondary circuit. With Tc = 35 °C, the condenser share (18.6 %) is lower than would appear at 15 °C.\n📐 Exergy Balance ABWR RBMK-1000 — Tk = 324 °C η Xh = 65.2 %, η energy = 33.7 %. Direct-cycle boiling water channel reactor, 284 °C / 285 bar.\nComponent group % Steam Generator (Tk = 324 °C) 30.1 % Turbines (HP1–HP4, LP1–LP4) 38.2 % Condenser 17.0 % FWH (LP1–LP5, MP1) 7.1 % Reheaters 1 and 2 (net) 5.4 % Six feedwater heaters (7.1 %) operate over a wide temperature range. HP1 turbine is the most loaded individual stage (10.3 %), fed by direct-cycle steam at moderate quality.\n📐 Exergy Balance RBMK-1000 VVER-1000 — Tk = 313 °C η Xh = 65.9 %, η energy = 33.5 %. Modern horizontal steam generator (PGV-1000M), primary at 278 °C / 160 bar.\nComponent group % Steam generator + economiser (Tk = 313 °C) 19.7 % Turbines (HP1–HP3, LP1–LP5) 46.8 % Condenser 17.8 % FWH (HP1, HP3, HP4, LP1–LP4) 9.3 % Reheaters 1 and 2 (net) 3.4 % The source (19.7 %) is the lowest among all WCR detailed models, reflecting the well-matched primary temperature and horizontal SG design. The turbines (46.8 %) are consequently the dominant component — a paradoxical sign of a well-optimised source side.\n📐 Exergy Balance VVER-1000 VVER-70 — Tk = 283 °C η Xh = 57.5 %, η energy = 27.7 %. K-70-29 turbine, saturated steam at 29 bar, moisture separator only (no reheater). Novovoronezh units 1–2, 210 MWe (3 × 70 MWe), 1964 design.\nComponent group % Source (generator + economiser, Tk = 283 °C) 39.5 % Turbines 36.6 % Condenser 19.2 % FWH 1.6 % Modelling note: The K-70-29 turbine operates on saturated steam with a moisture separator only — no reheater. The feedwater temperature Talim is not documented in available sources for the Novovoronezh plant; it has been estimated from the known thermal power (760 MWth) and electrical output (210 MWe). A ±20 °C uncertainty on Talim propagates to approximately ±3 pts on the source % and FWH % individually, but affects η Xh by less than ±0.5 pt.\n📐 Exergy Balance VVER-70 CANDU Pickering — Tk = 292 °C η Xh = 68.4 %, η energy = 33.5 %. Natural-uranium reactor, primary at 260 °C / 45 bar.\nComponent group % Steam Generator (Tk = 292 °C) 24.1 % Turbines (HP1, HP2, LP1–LP5) 34.1 % Condenser 25.7 % FWH (LP1–LP3, HP5, HP6) 3.2 % Reheater 2 (net) 4.8 % The condenser (25.7 %) is the highest among all detailed WCR models — a consequence of the low primary temperature (260 °C) and a relatively simple feedwater heating circuit.\n📐 Exergy Balance CANDU Pickering Superphénix — Tk = 600 °C η Xh = 64.7 %, η energy = 43.3 %. Sodium-cooled fast reactor with intermediate Na–Na heat exchanger (IHX). Steam at 487 °C.\nComponent group % Reactor core (Tk = 600 °C) 25.6 % IHX (Na primary → Na secondary) 4.1 % SG economiser 9.8 % SG evaporator 5.4 % SG superheater 11.5 % SG total 26.7 % Reheater (net) 4.5 % FWH (HP1, HP2, FWH2) 3.2 % Condenser 16.0 % Turbines (HP1–HP4, LP1–LP3) 16.0 % The SG superheater (11.5 %) is the dominant SG component — steam rising from saturation (~310 °C) to 487 °C against secondary sodium. The turbines (16.0 %) are the most balanced of all reactors. The IHX costs only 4.1 % for its fundamental safety function.\n📐 Exergy Balance Superphénix HTR-PM — Tk = 624 °C η Xh = 58.6 %, η energy = 41.7 %. Helium coolant at 750 °C outlet, six-stage turbine, steam at 566 °C / 138 bar.\nComponent group % Reactor core (Tk = 800 °C) 40.0 % Steam generator He→steam 27.7 % Condenser 8.6 % Turbines T1–T6 13.6 % FWH (HPH4 + LPH1–3) 8.3 % He blower + pumps 0.8 % Note on source accounting: The steam generator (20.6 %) is modelled as an internal exchanger without a Tk annotation and is not counted in the Source % column above.\nThe full source chain (core + SG) represents 64.1 % of total irreversibilities — comparable to the AGR structure, where the CO₂ circuit also contributes significantly to the source term.\nHTR-PM Shindao Bay: a second exergy balance has been computed from operational data published by Dong et al. (Nat. Commun. 16, 2778, 2025), based on the HMI readings of the actual plant. The Shindao Bay plant was operating at ~80 % of rated power, with turbine polytropic efficiencies of ~70 % (vs 83–93 % at nominal). The exergy balance reveals a drop from η Xh = 60.9 % to 50.4 % — entirely attributable to the turbines, which rise from 18.9 % to 30.5 % of total irreversibilities. The source and condenser contributions are barely affected.\nA full comparison between the nominal design and the Shindao Bay operating data is presented on the dedicated HTR-PM page.\n📐 Exergy Balances HTR-PM nominal HTR-PM Shindao Bay — model based on HMI data from Dong et al. (2025), not validated by original authors → See also: HTR-PM — Design vs Shindao Bay operating data\nCanadian SCWR — Tk = 670 °C η Xh = 68.5 %, η energy = 47.6 %. Supercritical water-cooled reactor, direct cycle, coolant outlet at 625 °C / 25 MPa. The highest η energy of all reactors in the corpus — a direct consequence of the supercritical steam conditions.\nComponent group % Source (Tk = 670 °C) 51.9 % Turbines (HP1, IP1–IP2, LP1–LP3) 20.1 % Condenser 11.1 % FWH (LP1–LP4, deaerator, HP5–HP8) 10.5 % Reheater (net) 4.1 % Pumps, vanes 2.3 % The source dominates at 51.9 % — seemingly paradoxical for a high-efficiency reactor, but thermodynamically consistent: at Tk = 670 °C the Carnot factor (1 − T₀/Tk) is 0.570, so even a well-matched heat exchange still attributes a large fraction of the exergy budget to the source. The condenser (11.1 %) is among the lowest in the corpus — only the AGR and HTR-PM go lower — a direct benefit of the high steam temperature.\nThe FWH contribution (10.5 %) is notable: nine feedwater heating stages (4 LP heaters, a deaerator and 4 HP heaters) operating over a wide temperature range from the condenser (~30 °C) to the supercritical feedwater inlet (~314 °C) generate significant mixing irreversibilities. This is the thermodynamic price of regenerative heating in a supercritical direct cycle.\nNote on the SCWR model: the Canadian SCWR design studied here is based on the pre-conceptual design described in Chatoorgoon (2008) and Leung et al. (2010). Primary data for a validated prototype are not yet available. The exergy balance reflects the thermodynamic model used in Chapter 8 of the book.\n📐 Exergy Balance Canadian SCWR EPR Flamanville 3 — Tk = 334 °C η Xh = 73.4 %, η energy = 38.5 %. Eight feedwater heaters, double reheat, steam at 294 °C / 78 bar. The most thermodynamically efficient reactor in the corpus.\nComponent group % Steam generator + economiser (Tk = 334 °C) 30.0 % Turbines (HP1–HP3, IP1–IP2, LP1–LP4) 32.8 % Condenser 22.7 % Feedwater heaters (FWH6, FWH7, LP1–LP4) 1.5 % Reheaters (net) 3.7 % Vanes, mixers, pumps 9.3 % The FWH contribution (1.5 %) is the lowest in the corpus — eight stages each operating at a small temperature difference. No single component dominates: this well-distributed balance is the signature of a highly optimised cycle.\n📐 Exergy Balance EPR Flamanville 3 Cross-Reactor Observations Condenser and η energy: as η energy increases, condenser % systematically decreases — from 25.7 % (CANDU, 33.5 %) to 9.7–10.4 % (AGR, HTR, 41–44 %). High-temperature cycles reject proportionally less heat to the cold source.\nFWH importance: VVER-1000 (9.3 %) and RBMK (7.1 %) show significantly higher FWH contributions than the EPR (1.5 %) — reflecting wider temperature ranges in their feedwater heating systems.\nTurbine loading paradox: the VVER-1000 (46.8 %) has the highest turbine % of all detailed models despite its good η Xh (65.9 %). A well-optimised source (19.7 %) leaves more relative weight to the turbines — this is a sign of balance quality, not inefficiency.\n","title":"Detailed Models — Component Analysis","uri":"https://server.s4e2.com/crc/tcnpp/resources/exergy/detailed/"},{"content":"Resources 📘 Chapter 2: Official Nuclear Energy Resources Key Organizations, Regulatory Bodies, Research Institutions, and Innovative Projects\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 2 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nThese links point to official websites and databases of international organizations, national regulatory bodies, and research institutions. Some projects listed here are ongoing or under review — please refer to the linked sources for the most up-to-date information. 📌 International Organizations Key Concepts Covered: Global nuclear governance, safety standards, and international cooperation. Complementary Resources: 🌐 Global Nuclear Governance and Safety International Atomic Energy Agency (IAEA) — The world\u0026rsquo;s central intergovernmental forum for scientific and technical cooperation in the nuclear field. IAEA Official Website →\nNuclear Energy Agency (NEA) – OECD — Facilitates cooperation among countries with advanced nuclear technology infrastructures. NEA Official Website →\nWorld Nuclear Association (WNA) — Provides global nuclear industry information and promotes nuclear energy. WNA Official Website →\n📌 National Nuclear Regulatory Bodies Key Concepts Covered: Safety regulation of nuclear power plants and materials at the national level. Complementary Resources: 🏛️ Safety and Regulation U.S. Nuclear Regulatory Commission (NRC) — Regulates commercial nuclear power plants and the use of nuclear materials in the United States. NRC Official Website →\nFrench Nuclear Safety Authority (ASN) — Ensures nuclear safety and radiation protection in France. ASN Official Website →\nUK Office for Nuclear Regulation (ONR) — Regulates nuclear safety and security in the United Kingdom. ONR Official Website →\n📌 Nuclear Research and Development Key Concepts Covered: Scientific and technical resources for nuclear energy research. Complementary Resources: 🔬 Scientific and Technical Resources European Nuclear Society (ENS) — Promotes the advancement of nuclear science and technology in Europe. ENS Official Website →\nIdaho National Laboratory (INL) – U.S. DOE — A leading center for nuclear energy research and development in the United States. INL Official Website →\nCEA (French Alternative Energies and Atomic Energy Commission) — A key player in nuclear research, energy, and technology in France. CEA Official Website →\n📌 Nuclear Energy Education and Training Key Concepts Covered: Education, training, and professional development in nuclear science and engineering. Complementary Resources: 🎓 Learning and Professional Development MIT Nuclear Reactor Laboratory — Provides education, research, and training in nuclear science and engineering. MIT NRL Official Website →\nEuropean Nuclear Education Network (ENEN) — Promotes higher education and training in the nuclear field across Europe. ENEN Official Website →\nWorld Nuclear University (WNU) — Offers leadership development and education for the global nuclear industry. WNU Official Website →\n📌 Nuclear Energy Data and Statistics Key Concepts Covered: Reports and databases on nuclear power reactors and fuel cycles worldwide. Complementary Resources: 📊 Reports and Databases IAEA PRIS (Power Reactor Information System) — Provides comprehensive data on nuclear power reactors worldwide. IAEA PRIS Database →\nWorld Nuclear Association – Nuclear Power Reactors — Detailed information on nuclear reactors, fuel cycles, and global nuclear energy trends. WNA Reactor Database →\nOECD-NEA Data Bank — Provides nuclear data, computer programs, and services for the nuclear community. NEA Data Bank →\n📌 Innovative Nuclear Projects Key Concepts Covered: Advanced reactor technologies, including SMRs, Generation IV reactors, fusion, and hybrid systems. Complementary Resources: ⚛️ Small Modular Reactors (SMRs) NuScale Power (USA) — Developer of the first SMR to receive U.S. design certification. NuScale Official Website →\nRolls-Royce SMR (UK) — UK-based SMR project aiming for scalable, low-cost nuclear energy. Rolls-Royce SMR Official Website →\nEDF – Nuward (France) — French SMR project designed for flexibility and safety. EDF Nuward Official Website →\n⚛️ Generation IV Reactors TerraPower (USA) – Natrium Reactor — Development of advanced sodium-cooled fast reactors. TerraPower Official Website →\nASTRID Project (France/CEA) — Prototype for sodium-cooled fast reactors (project currently under review). CEA ASTRID Information →\n🔆 Nuclear Fusion Projects ITER (International Thermonuclear Experimental Reactor) — The world\u0026rsquo;s largest fusion experiment, aiming to demonstrate the feasibility of fusion energy. ITER Official Website →\nSPARC (MIT \u0026amp; Commonwealth Fusion Systems) — Compact tokamak project targeting net energy gain from fusion. CFS SPARC Official Website →\nWendelstein 7-X (Germany) — Stellarator fusion device exploring steady-state plasma operation. Max Planck Institute – Wendelstein 7-X →\n♻️ Innovative Fuel Cycles and Waste Management MYRRHA (Belgium) — Accelerator-driven system for nuclear waste transmutation and research. MYRRHA Official Website →\nTransmutation and Advanced Fuel Research (CEA, France) — Research on closing the nuclear fuel cycle and reducing radioactive waste. CEA Fuel Cycle Research →\n🔗 Hybrid and Cross-Disciplinary Projects U.S. DOE – GAIN Initiative — Promotes integration of nuclear energy with renewable sources. DOE GAIN Initiative →\nHigh-Temperature Steam Electrolysis (HTSE) — Using nuclear heat for efficient hydrogen production. INL Hydrogen Production Research →\n📌 Overview of Nuclear Fission Reactors Key Concepts Covered: Main types of nuclear reactors, classified by fuel type, neutron spectrum, moderator, coolant, thermodynamic cycle, and working fluid. Complementary Resources: 🔄 Guided Exploration GE: TCNPP-1: Overview of Nuclear Fission Reactors — A non-exhaustive presentation of the main types of nuclear reactors and their distinguishing characteristics. GE: TCNPP-1: Overview of Nuclear Fission Reactors →\n📌 Startups and Private Initiatives Key Concepts Covered: Emerging private sector contributions to advanced nuclear energy. Complementary Resources: Oklo (USA) — Developing micro-reactors for clean, off-grid power. Oklo Official Website →\nNewcleo (Italy/UK) — Focused on lead-cooled fast reactors and MOX fuel. Newcleo Official Website →\nSeaborg Technologies (Denmark) — Compact molten salt reactors for floating power plants. Seaborg Official Website →\n📩 Need Help or Further Clarification? If you have questions about these resources, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter2/_resources/"},{"content":"Important Information 📚 Complementary Digital Resources On these pages, you will find links and guidance to digital resources designed to enrich and expand the explanations provided in the book. These materials are intended to deepen your understanding and offer practical applications of the concepts discussed.\nTypes of Resources Available We provide several types of complementary materials, including:\nDiapason audio sessions (guided explanations and discussions), Guided explorations (step-by-step interactive simulations), Thematic pages from the Thermoptim-Unit portal. 🔍 Important Notes 1. About Diapason Sessions Many of the Diapason sessions were created several years ago. As a result:\nSome Thermoptim screenshots may appear outdated. Certain titles and terms have been updated to align with current Anglo-Saxon terminology (for example, \u0026ldquo;controller\u0026rdquo; instead of older French-inspired terms like \u0026ldquo;driver\u0026rdquo; or \u0026ldquo;pilot\u0026rdquo;). These differences are minor and should not hinder comprehension—the core concepts and methodologies remain fully relevant. 2. About Guided Explorations The links to guided explorations will take you to their online versions, which are not directly coupled with Thermoptim. To work with the full interactive application:\nDownload and install the Thermoptim version on your computer. Access the explorations directly from the application’s menu. 💡 How to Use These Resources For learners and students: Use these materials to reinforce your understanding of key concepts through practical examples and guided exercises. For educators and professionals: Integrate these resources into your teaching or training programs to provide hands-on, real-world applications of thermodynamic principles. For all users: If you encounter any technical terms or interfaces that seem unfamiliar, refer to the latest version of Thermoptim or the Thermoptim-Unit portal for updated information. 📩 Need Help? If you have questions about accessing or using these resources, or if you’d like further clarification on any of the materials, please don’t hesitate to contact us.\nRenaud Gicquel – Bridging theory and practice in energy systems education.\n","title":"Important Information","uri":"https://server.s4e2.com/crc/tcnpp/general/_avertissement/"},{"content":"Resources 📘 Appendix 1: Thermodynamic Diagrams and Heat Exchangers Complementary Resources, Guided Explorations, and Methodological Guides\n⚠️ Important Notes About These Resources The resources on this page complement the content of Appendix 1 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. Some resources are historical examples from the Thermoptim portal, while others are updated models developed specifically for the book. They should not have any consequences on the understanding of the presented concepts. 📌 A1.1 Thermodynamic Diagrams of Pure Substances Key Concepts Covered: Properties of pure substances and their representation in thermodynamic diagrams. Use of standard charts (e.g., T-s, h-s, P-h diagrams) for cycle analysis. Complementary Resources: 📄 Thermodynamic Diagrams Collection Links to Various Thermodynamic Diagrams — Thermoptim provides a collection of thermodynamic diagrams for pure substances, useful for visualizing and analyzing cycles. (Available directly within the Thermoptim software.)\n📊 Diapason Session: Properties of Substances and Standard Charts (S04aEn) Session S04aEn — Explains the properties of pure substances and how to use standard thermodynamic charts for analysis. Diapason Session: Properties of Substances and Standard Charts →\n📌 A1.2 Thermodynamics of Heat Exchangers Key Concepts Covered: Fundamentals of heat exchanger thermodynamics. Analysis of heat transfer processes and efficiency. Application of the NTU method. Complementary Resources: 📊 Diapason Session: Thermodynamics of Heat Exchangers (S18En) Session S18En — Explores the thermodynamic principles of heat exchangers, including heat transfer mechanisms, efficiency calculations, and design considerations. Diapason Session: Thermodynamics of Heat Exchangers →\n📌 Design of Thermal Systems: Steam Plant Condenser Key Concepts Covered: Design and analysis of steam plant condensers. Heat rejection processes and thermal efficiency. Integration of condensers in steam power cycles. Complementary Resources: 🔄 Guided Exploration: Design of a Steam Plant Condenser (STEAM-2) GE: STEAM-2 — Guides you through the design and analysis of a steam plant condenser using a realistic model in Thermoptim. GE: STEAM-2: Design of a Steam Plant Condenser →\n📌 Methodological Page: Heat Exchangers Key Concepts Covered: Methodological approach to modeling and analyzing heat exchangers. Practical guidance for design and optimization. Case studies and real-world applications. Complementary Resources: 📖 Methodological Page Heat Exchangers – Methodological Approach — Provides a detailed methodological approach to modeling heat exchangers, including design principles, efficiency analysis, and practical applications. Methodological Page: Heat Exchangers →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/appendix1/_resources/"},{"content":"Resources 📘 Appendix 2: Turbines and Stodola\u0026rsquo;s Law Complementary Resources and Methodological Guides\n⚠️ Important Notes About These Resources The resources on this page complement the content of Appendix 2 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. Some resources are historical examples from the Thermoptim portal, while others are updated models developed specifically for the book. They should not have any consequences on the understanding of the presented concepts. 📌 Turbines and Stodola\u0026rsquo;s Law Key Concepts Covered: Analysis of flow and efficiency in turbines and compressors. Transition from the polytropic approach to the isentropic approach Application of Stodola\u0026rsquo;s law in turbomachinery. Integration of Stodola\u0026rsquo;s law in Thermoptim models. Complementary Resources: 🔄 Guided Exploration C-M1-V3: Steam power plants with reheat GE: C-M1-V3: Steam power plants with reheat → This GE provides explanations on the polytropic concept.\n📖 Thematic Page: Turbines Turbines and Stodola\u0026rsquo;s Law — Explains the fundamentals of turbines and presents Stodola\u0026rsquo;s law, including its practical application in turbomachinery modeling. Explore Turbines and Stodola\u0026rsquo;s Law →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/appendix2/_resources/"},{"content":"Resources 📘 Chapter 1: Analysis of Energy Systems Complementary Resources, Guided Explorations, and Simulation Tools\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 1 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. Some resources are historical examples from the Thermoptim portal, while others are updated models developed specifically for the book. It is therefore possible that there are discrepancies between the examples provided in the portal and those selected for this book. They should not have any consequences on the understanding of the presented concepts. 📌 1.1 Analysis of Energy Systems Key Concepts Covered: Modeling of simple and complex energy systems. General methodological approach to energy analysis. Complementary Resources: 📖 Methodological Guides Modeling Simple and Complex Systems — A guide presenting how to model simple and complex thermodynamic systems. Guide: Modeling simple and complex systems →\nGeneral Methodological Approach — An overview of the methodological approach used throughout the book. Methodological approach →\n📌 1.1.2 Illustration: The Steam Power Plant Key Concepts Covered: Steam power plant cycles as an introductory illustration. Complementary Resources: 📖 Thematic Page Steam Power Plant Cycles — An overview of thermodynamic cycles used in steam power plants. Steam power plant cycles →\n📌 1.2.1 Complete Cycle Example: Fla3 Key Concepts Covered: Flamanville 3 full cycle as a practical example. Complementary Resources: 🔄 Flowsheet Flamanville 3 Full Load Flowsheet — A detailed flowsheet of the complete Flamanville 3 cycle at full load. Flamanville 3 Full Load Flowsheet →\n📌 1.2.8 Example: Modeling a Steam Turbine Key Concepts Covered: Equation generation for a steam turbine model. Solving in EES and IT environments. Complementary Resources: 🔄 Guided Exploration EQUA-01: Generating the Equations of a Steam Turbine Model — Development of a standalone steam turbine model, including generation of equations and solving in EES and IT (refer to the demo version of EES for practical implementation). GE: EQUA_01: Generating the Equations of a Steam Turbine Model →\n📌 1.3.3 Discovering Thermoptim Key Concepts Covered: Introduction to Thermoptim through a vapor cycle example. Complementary Resources: 🔄 Guided Exploration Discovery of Thermoptim (Vapor Cycle) — A first guided exploration introducing Thermoptim through a vapor power cycle. Thermoptim Discovery (Vapor Cycle) →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter1/_resources/"},{"content":"Resources 📘 Chapter 3: Steam Power Plant and Gas Turbine Cycles Complementary Resources, Guided Explorations, and Simulation Tools\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 3 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. Some resources are historical examples from the Thermoptim portal, while others are updated models developed specifically for the book. They should not have any consequences on the understanding of the presented concepts. 📌 3.2 Steam Power Plant and Gas Turbine Cycles Key Concepts Covered: Simple steam power plant cycles as an introduction to the basic steam cycle. Simple helium closed-cycle gas turbine as an introduction to nuclear gas turbine cycles. Complementary Resources: 🔄 Guided Explorations Exploration of a Simple Steam Power Plant — Serves as an introduction to the basic steam cycle. GE: S-M3-V7: Exploration of a simple steam power plant →\nExploration of a Simple Helium Closed-Cycle Gas Turbine — Serves as an introduction to the basic high-temperature nuclear cycle. GE: TCNPP-5b: Exploring a High-Temperature Nuclear Cycle →\n📌 3.3 Comparison with the Carnot Cycle in the Entropy Diagram Key Concepts Covered: Steam plant behavior in the (T,s) entropy diagram. Gas turbine behavior in the (T,s) entropy diagram. Complementary Resources: 🔄 Guided Explorations Exploration of a Steam Plant in the Entropy Diagram — Useful for comparing with the Carnot cycle in the entropy diagram. GE: Steam Plant in (T,s) Diagram →\nExploration of a Gas Turbine in the Entropy Diagram — Useful for comparing with the Carnot cycle in the entropy diagram. GE: Gas Turbine in (T,s) Diagram →\n📌 3.4.4 Exergy Balances and Exergy Structures Key Concepts Covered: Exergy balances of steam and gas turbine cycles. Productive exergy structures for various thermodynamic cycles. Complementary Resources: 📊 Slides Diapason S06En: Exergy Balances — Covers exergy balances (does not address exergy structures).\n🔄 Guided Explorations BESP-1: Exergy Balance and Productive Structure of a Simple Steam Cycle — Introduction to exergy balance and productive structure for steam cycles. GE: BESP-1 Steam Cycle →\nBESP-2: Exergy Balances and Productive Structures of Different Cycles — Exergy analysis across various thermodynamic cycles. GE: BESP-2 Different Cycles →\n📌 3.4.5 Process Integration by the Pinch Method Key Concepts Covered: Introduction to the pinch method for thermal process integration. Application of the pinch method to an industrial example. Complementary Resources: 📊 Slides Diapason IT1En: Introduction to the Pinch Method — Introduces the theoretical foundations of the pinch method. IT1En: Introduction to the pinch method →\nDiapason IT2En: Thermal Integration of the Gourlia Example with Thermoptim — Application of the pinch method to a practical industrial case. IT2En: Application of the pinch method to the Gourlia case →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter3/_resources/"},{"content":"Resources 📘 Chapter 4: Advanced Steam Cycles Complementary Resources, Guided Explorations, and Simulation Tools\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 4 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. Some resources are historical examples from the Thermoptim portal, while others are updated models developed specifically for the book. They should not have any consequences on the understanding of the presented concepts. 📌 4.1.4 Cycle with Reheat Key Concepts Covered: Reheat steam cycles and their thermodynamic advantages. Extraction steam cycles for feedwater heating. Exergy balance and productive structure of steam cycles. Complementary Resources: 🔄 Guided Explorations Introduction to Reheat Steam Cycles — Serves as an introduction to reheat steam cycles (even if the boiler is not nuclear). GE: VapeurResurch7cci1_en →\nIntroduction to Extraction Steam Cycles — Serves as an introduction to extraction (regenerative feedwater heating) steam cycles. GE: VapeurResurPrel7cci1_en →\nExergy Balance and Productive Structure of a Simple Steam Cycle — Introduction to exergy balance and productive structure. GE: BESP-1 Steam Cycle →\n📖 Models and Additional Information Model of a Closed Feedwater Heater with Cascaded Drains — Details the cascaded drain feedwater reheater model used in steam cycle simulations. Model: Closed Feedwater Heater →\n📌 4.2 Supercritical Cycles Key Concepts Covered: Supercritical steam cycles and their performance characteristics. Complementary Resources: 📖 Thematic Page Supercritical Cycles Overview — A comprehensive overview of supercritical steam cycles and their applications. Supercritical Cycles →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter4/_resources/"},{"content":"Resources 📘 Chapter 5: Medium Temperature Steam Power Cycles Complementary Resources, Guided Explorations, and Simulation Tools\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 5 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. Some resources are historical examples from the Thermoptim portal, while others are updated models developed specifically for the book. They should not have any consequences on the understanding of the presented concepts. 📌 5.7 Moisture Separator Reheater (MSR) Key Concepts Covered: Moisture Separator Reheater (MSR) principles and design. Simplified Pressurized Water Reactor (PWR) cycle thermodynamics. Complementary Resources: 🔄 Guided Exploration GE: TCNPP-2: Cycle of Pressurized Water Reactors (PWR) — Introduction to the principles of the Moisture Separator Reheater and the simplified PWR cycle. GE: TCNPP-2: Cycle of Pressurized Water Reactors (PWR) →\n📌 5.9.2 Thermodynamic Cycles of Electricity-Generating Water-Cooled Reactors Key Concepts Covered: WCR thermodynamic cycles for electricity generation. NUSCLE reactor cycle modeling. Complementary Resources: 📖 Resources on WCR Thermodynamic Cycles Complementary Resources: 📖 NUSCLE Software Information Information on the NUSCLE software, relevant for understanding Water Cooled Reactors (WCR). Explore NUSCLE →\n🔄 Guided Exploration TCNPP-3: Feedwater System of a PWR Nuclear Power Plant GE: TCNPP-3: Feedwater System of a PWR Nuclear Power Plant →\n📌 5.10 ORC Power Plants Key Concepts Covered: Organic Rankine Cycle (ORC) power plants and their applications. Complementary Resources: 📖 Thematic Page ORC Power Plants Overview — A comprehensive resource on Organic Rankine Cycle power plants and their applications. Thematic Page: ORC Cycles →\n📌 5.11 Binary Cycles Key Concepts Covered: In water-ammonia binary cycles, steam is replaced in the final stage of its low-pressure expansion by ammonia, which under the same temperature conditions is approximately 120 times denser.\nComplementary Resources: 🔄 Guided Exploration TCNPP-4: Exploring a Water-Ammonia Binary Cycle GE: TCNPP-4: Exploring a Water-Ammonia Binary Cycle →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter5/_resources/"},{"content":"Resources 📘 Chapter 6: Gas Turbine Cycles and Supercritical CO₂ Complementary Resources, Guided Explorations, and Simulation Tools\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 6 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. Some resources are historical examples from the Thermoptim portal, while others are updated models developed specifically for the book. They should not have any consequences on the understanding of the presented concepts. 📌 6.1.1 Energy and Exergy Balances of the Simple Cycle Key Concepts Covered: Exergy balances and exergy structures of different thermodynamic cycles. Complementary Resources: 🔄 Guided Exploration Exergy Balances and Exergy Structures of Different Cycles — Focuses on exergy balances and productive structures for various thermodynamic cycles. GE: BESP-2: Exergy Balances and Productive Structures of Different Cycles →\n📌 6.1.2 Cycle Improvements Key Concepts Covered: Regenerative cycle variant and its thermodynamic benefits. Fractional compression cycle for improved efficiency. High-temperature nuclear cycle using a helium-nitrogen mixture Brayton cycle. Complementary Resources: 🔄 Guided Explorations Regenerative Cycle Variant — Exploration of a regenerative gas turbine cycle. GE: C-M2-V2: Regeneration gas turbine →\nFractional Compression Cycle Variant — Exploration of a fractional compression cycle. GE: BESP-2: Exergy balances and productive structures of different cycles →\nHigh-Temperature Nuclear Cycle — Exploration of a helium-nitrogen mixture Brayton cycle with an intermediate heat exchanger, applied to a high-temperature nuclear cycle. GE: C-M4-V4: High temperature nuclear cycle →\n📌 6.2 Supercritical CO₂ Cycles Key Concepts Covered: Supercritical CO₂ (sCO₂) cycles and their nuclear applications. Span-Wagner CO₂ model for high-precision thermodynamic calculations. Complementary Resources: 📖 Models and Thematic Pages Span-Wagner CO₂ Model in CTPlib — High-precision CO₂ model for supercritical thermodynamic calculations. CTPlib: CO₂ Model →\nThematic Page: Supercritical CO₂ Cycles — Comprehensive overview of supercritical CO₂ cycles and their applications. sCO₂ Cycles →\n🔄 Guided Exploration GE: TCNPP-6: Exploring Supercritical CO₂ Nuclear Cycles — Focuses on exergy balances and structures for various thermodynamic cycles, with detailed explanations on external diagrams. GE: TCNPP-6: Exploring Supercritical CO₂ Nuclear Cycles →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter6/_resources/"},{"content":"Resources 📘 Chapter 7: Combined Cycles, Desalination, and Hydrogen Production Complementary Resources, Guided Explorations, and Simulation Tools\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 7 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. Some resources are historical examples from the Thermoptim portal, while others are updated models developed specifically for the book. They should not have any consequences on the understanding of the presented concepts. 📌 7.1.2 Single Pressure Combined Cycle Key Concepts Covered: Single pressure combined cycle design and thermodynamic analysis. Complementary Resources: 🔄 Guided Exploration Single Pressure Combined Cycle — Introduction to the thermodynamics and modeling of a single pressure combined cycle. GE: C-M3-V1: Single pressure combined cycle →\n📊 Slides Single Pressure Combined Cycle Exercise — A slide set accompanying the combined cycle exercise. Diapason: S41En →\n📌 7.1.3 Dual Pressure Level Combined Cycle Key Concepts Covered: Optimization of a dual pressure combined cycle using the pinch analysis method. Complementary Resources: 🔄 Guided Exploration Optimization of a Dual Pressure Combined Cycle by Pinch Analysis — Applies the pinch method to optimize a dual pressure level combined cycle. GE: OPT-2: Optimization of a combined cycle by the pinch method →\n📌 7.1.5 Kalina Cycle Key Concepts Covered: Kalina cycle thermodynamics and applications. Complementary Resources: 📖 Thematic Page Kalina Cycle Overview — An introduction to the Kalina cycle and its thermodynamic principles. Kalina Cycle →\n📌 7.2 Desalination of Seawater Key Concepts Covered: Desalination processes and evapoconcentration techniques. Salt water thermodynamic model for simulation. Complementary Resources: 📖 Thematic Pages and Models Desalination and Evapoconcentration — An overview of desalination processes and evapoconcentration methods. Desalination Overview →\nSalt Water Model — Thermodynamic model for salt water used in desalination simulations. Salt Water Model →\n📌 7.3.3 Electrolysers Key Concepts Covered: Electrolyser modeling for hydrogen production using nuclear heat. Complementary Resources: 📖 Model Electrolyser Model — Thermodynamic model for high-temperature steam electrolysis used in hydrogen production. Electrolyzer Model →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter7/_resources/"},{"content":"Resources 📘 Chapter 8: Detailed Flowsheets of Nuclear Power Plant Cycles Complementary Resources and SVG Flowsheets\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 8 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nThe flowsheets below are SVG diagrams accessible directly in a browser. Most reactor types are provided in two layouts: horizontal (full-width view) and stacked (compact view). 8.1 — AGR Hartlepool · 625 MWe United Kingdom · Gas-cooled · Graphite moderated · CO₂ · British design\nComplementary Resources: 🔄 Flowsheets Figure 8.1.1 — Horizontal flowsheet Figure 8.1.1 — Stacked flowsheet 📌 8.2 NuScale Small Modular Reactor (50 MW) Complementary Resources: 🔄 Flowsheets Figure 8.2.1: Detailed Flowsheet of the 50 MW NuScale Cycle (horizontal) NuScale 50 MW Cycle – Horizontal →\n📌 8.3 NuScale Small Modular Reactor (77 MW) Complementary Resources: 🔄 Flowsheets Figure 8.3.1: Detailed Flowsheet of the 77 MW NuScale Cycle NuScale 77 MW Cycle – Horizontal →\n📌 8.4 Advanced Boiling Water Reactor (ABWR – 1350 MW) Complementary Resources: 🔄 Flowsheets Figure 8.4.1: Detailed Flowsheet of the 1350 MW ABWR Cycle (horizontal) ABWR 1350 MW Cycle – Horizontal →\nFigure 8.4.1: Detailed Flowsheet of the 1350 MW ABWR Cycle (stacked) ABWR 1350 MW Cycle – Stacked →\n--- 📌 8.5 RBMK Reactor (1000 MW) Complementary Resources: 🔄 Flowsheets Figure 8.5.1: Detailed Flowsheet of the 1000 MW RBMK Cycle (horizontal) RBMK 1000 MW Cycle – Horizontal →\nFigure 8.5.1: Detailed Flowsheet of the 1000 MW RBMK Cycle (stacked) RBMK 1000 MW Cycle – Stacked →\n--- 📌 8.6 VVER Reactor (1000 MW) Complementary Resources: 🔄 Flowsheets Figure 8.6.1: Detailed Flowsheet of the 1000 MW VVER Cycle (horizontal) VVER 1000 MW Cycle – Horizontal →\nFigure 8.6.1: Detailed Flowsheet of the 1000 MW VVER Cycle (stacked) VVER 1000 MW Cycle – Stacked →\n--- 📌 8.7 CANDU Pickering Reactor (550 MW) Complementary Resources: 🔄 Flowsheets Figure 8.7.1: Detailed Flowsheet of the 550 MW CANDU Pickering Cycle (horizontal) CANDU Pickering 550 MW Cycle – Horizontal →\nFigure 8.7.1: Detailed Flowsheet of the 550 MW CANDU Pickering Cycle (stacked) CANDU Pickering 550 MW Cycle – Stacked →\n--- 📌 8.8 Superphénix Fast Breeder Reactor (1175 MW) Complementary Resources: 🔄 Flowsheets Figure 8.8.1: Detailed Flowsheet of the 1175 MW Superphénix Cycle (horizontal) Superphénix 1175 MW Cycle – Horizontal →\nFigure 8.8.1: Detailed Flowsheet of the 1175 MW Superphénix Cycle (stacked) Superphénix 1175 MW Cycle – Stacked →\n📌 8.9 HTR-PM High-Temperature Gas-Cooled Reactor (67 MW) The Shindao Bay Operating Data Very little information is publicly available about the HTR-PM secondary circuit. The Shindao Bay model presented here was constructed from data visible in Figure 5 of Dong et al. (2025), which shows the Human-Machine Interface (HMI) of the plant\u0026rsquo;s coordinated control system. This operational dashboard displays helium, steam and feedwater temperatures, core power, electrical output, efficiency, power level, and mass flow rates.\nNote: this model has not been validated by the original authors. Despite several requests, it has proven impossible to obtain direct information on the secondary circuit. The extraction pressures and flow rates were assumed; a polytropic efficiency of 70 % was applied to all turbine stages — the value that alone reproduces the announced electrical output of 64 MWe.\nThe discrepancies are significant. The plant was operating at approximately 80 % of rated power, which partially explains the reduced performance.\nWe provide here the two models, the first corresponding to the available experimental data, and the second to the nominal performance.\nComplementary Resources: 🔄 Flowsheets Figure 8.9.1: Detailed Model of the 67 MW HTR-PM Cycle (horizontal) HTR-PM 67 MW Cycle – Horizontal →\nFigure 8.9.1: Detailed Model of the 67 MW HTR-PM Cycle (stacked) HTR-PM 67 MW Cycle – Stacked →\n--- 📌 8.10 Canadian Supercritical Water Reactor (SCWR – 1200 MW) Complementary Resources: 🔄 Flowsheets Figure 8.10.1: Detailed Model of the Canadian 1200 MW SCWR Cycle (horizontal) Canadian SCWR 1200 MW Cycle – Horizontal →\nFigure 8.10.1: Detailed Model of the Canadian 1200 MW SCWR Cycle (stacked) Canadian SCWR 1200 MW Cycle – Stacked →\n--- 🖥️ Steam Generator Controller for Flamanville 3 EPR PWR_SG_Controller - A controller class for the steam generator of the Flamanville 3 EPR.\n📩 Need Help or Further Clarification? If you have questions about these resources, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter8/_resources/"},{"content":"Resources 📘 Chapter 9: Methodological Approaches Complementary Resources and Methodological Guides\n⚠️ Important Notes About These Resources The resources on this page complement the content of Chapter 9 in Advanced Modeling of Thermodynamic Cycles of Nuclear Power Plants.\nModels and examples are accessible online but require the Thermoptim software for full interactivity. Download Thermoptim here to access the complete features. 📌 Methodological Guides Key Concepts Covered: Modeling of simple and complex energy systems. General methodological approach to energy system analysis. Complementary Resources: 📖 Guides Modeling Simple and Complex Systems — A guide presenting how to model simple and complex thermodynamic systems. Guide: Modeling simple and complex systems →\nGeneral Methodological Approach — An overview of the methodological approach used throughout the book. Methodological approach →\n📩 Need Help or Further Clarification? If you have questions about these resources or need assistance using Thermoptim, feel free to contact us.\n","title":"Resources","uri":"https://server.s4e2.com/crc/tcnpp/chapters/chapter9/_resources/"},{"content":"📋 Case Studies — Reactor Fact Sheets and Flowsheets These fact sheets summarise the key technical data for each of the 11 nuclear power plant case studies analysed in Chapter 8. Each sheet covers reactor technology, deployment history, key facts, and links to the detailed SVG flowsheets available on this companion site.\nThis page is complemented by the one that presents the exergy balances by reactors.\nSVG flowsheets are referenced using the same figure numbering as in the book.\n🗓️ Publication schedule — New fact sheet published every Tuesday morning.\n8.1 — AGR Hartlepool · 625 MWe United Kingdom · Gas-cooled · Graphite moderated · CO₂ · British design\n⚡ Key Parameters Parameter Value Net electric power 625 MWe Thermodynamic efficiency 41 % Coolant CO₂ Steam temperature 541 °C Steam pressure 170 bar Feedwater heaters 8 🔬 Reactor Technology The Advanced Gas-cooled Reactor (AGR) is the British successor to the Magnox reactor. It uses pressurised carbon dioxide (CO₂) as coolant and graphite as moderator. The fuel consists of lightly enriched uranium oxide (2.5–3.5 %) clad in stainless steel, which withstands higher gas temperatures (~650 °C) than Magnox (~400 °C), giving the AGR the highest thermodynamic efficiency (~41 %) among gas-cooled power reactors. The secondary steam cycle includes superheat and reheat with 8 feedwater heaters (FWH).\n🏭 Deployment History Plant Country Units Power First power Shutdown / Status Dungeness B UK 2 2 × 505 MWe 1983/85 Shutdown 2021/23 Hartlepool UK 2 2 × 605 MWe 1983/84 Scheduled Shutdown 2028 Heysham 1 UK 2 2 × 580 MWe 1983/84 Scheduled Shutdown 2028 Heysham 2 UK 2 2 × 615 MWe 1988/89 Scheduled Shutdown 2030 Hinkley Point B UK 2 2 × 480 MWe 1976 Shutdown 2022 Hunterston B UK 2 2 × 490 MWe 1976/77 Shutdown 2022 Torness UK 2 2 × 625 MWe 1988/89 Scheduled Shutdown 2030 📌 Key Facts AGR programme launched in the 1960s; 14 units commissioned between 1976 and 1989, all now permanently shut down or scheduled for decommissioning. Net efficiency ~41 %, the highest of all operational gas-cooled or light-water reactors. Hartlepool cycle modelled in the book with 8 FWH, superheat and reheat to 541 °C / 539 °C. No AGR has ever been exported; the design remains exclusively British. Relative economic failure: construction and operating costs significantly exceeded forecasts. 📐 SVG Flowsheets Figure 8.1.1 — Horizontal flowsheet Figure 8.1.1 — Stacked flowsheet 8.2 — NuScale US600 · 50 MWe USA · SMR · Natural-circulation PWR · Passive safety · NRC certified\n⚡ Key Parameters Parameter Value Electric power 50 MWe / module Total plant output 600 MWe (12 modules) Thermodynamic efficiency ~30 % Steam temperature 300 °C Steam pressure 34 bar Primary circulation Natural convection (no pumps) 🔬 Reactor Technology The NuScale Power Module (NPM) US600 is a fully passive Small Modular Reactor (SMR) of the pressurised water type. Its key feature is the integration of the reactor core, helical-coil steam generators, and the pressure vessel within a single compact cylindrical module submerged in a shared underground pool. Primary coolant circulation relies entirely on natural convection — no pumps required. A reference plant uses 12 modules for a total output of 600 MWe. The secondary steam cycle includes feedwater heaters in a simplified configuration compared with conventional PWRs.\n🏭 Deployment History Plant Country Units Power Status CFPP (Carbon Free Power Project), Idaho Falls USA 6–12 300–600 MWe Cancelled in November 2023 📌 Key Facts First SMR to receive a Standard Design Approval from the NRC (USA) in 2020. The CFPP project (Utah Associated Municipal Power Systems) was cancelled in November 2023 due to rising cost estimates. The design integrates the core and steam generators in a single pressurised cylindrical module. Fully passive safety: automatic shutdown and cooling without electrical power or human intervention for up to 72 hours.. The module is fully factory-fabricated and transportable by rail or road. 📐 SVG Flowsheet Figure 8.2.1 — Horizontal flowsheet 8.3 — NuScale US460 · 77 MWe USA · SMR · Natural-circulation PWR · Passive safety · Gen III+\n⚡ Key Parameters Parameter Value Electric power 77 MWe / module Total plant output 924 MWe (12 modules) Thermodynamic efficiency ~30 % Thermal power 250 MWth / module Primary circulation Natural convection (no pumps) 🔬 Reactor Technology The NuScale US460 is the uprated version of the US600 module. Thermal power per module is increased to 250 MWth (vs 160 MWth for the US600), improving economics of scale while retaining the integrated architecture and natural circulation. The helical-coil steam generator design is optimised for slightly higher steam pressures and temperatures. A reference plant groups 12 modules of 77 MWe for a total of 924 MWe. A new NRC design certification process is underway for the US460.\n🏭 Deployment History Plant Country Units Power Status Projects under negotiation (Romania, Poland, etc.) Multiple 12 924 MWe 2030s 📌 Key Facts Uprated version of the US600: thermal power per module increased from 160 MWth to 250 (+56 %). The 2020 NRC certification for the US600 does not directly cover the US460; a new approval process is under way. Cancellation of CFPP in 2023 affected commercial momentum, but NuScale continues development and international contracts. Active collaboration with Romania (Doicești), Poland and Bulgaria for 2030+ deployment. Shares the integrated architecture and passive safety features of the US600. 📐 SVG Flowsheet Figure 8.3.1 — Horizontal flowsheet 8.4 — ABWR · 1350 MWe Japan · BWR · Direct cycle · Generation III · GE-Hitachi\n⚡ Key Parameters Parameter Value Electric power 1,350 MWe Thermodynamic efficiency ~34 % Steam temperature 288 °C Steam pressure 69 bar Turbine extraction stages 11 🔬 Reactor Technology The Advanced Boiling Water Reactor (ABWR) is a Generation III reactor developed by General Electric, Hitachi and Toshiba. Unlike a PWR, the cycle is direct: steam produced in the core feeds the turbines without an intermediate steam generator. Ten internal recirculation jet pumps replace the large external recirculation lines of earlier BWRs. The secondary cycle is complex: a moisture separator–reheater (MSR) between the HP and LP turbines, 11 extraction stages for feedwater heating, and three staged condensate pumps.\n🏭 Deployment History Plant Country Units Power First power Status Kashiwazaki-Kariwa 6 \u0026amp; 7 Japan 2 2 × 1,356 MWe 1996/97 In service Hamaoka 5 Japan 1 1,380 MWe 2005 Shut down in 2011 * Shika 2 Japan 1 1,206 MWe 2006 Shut down in 2011 * Lungmen 1 \u0026amp; 2 Taiwan 2 2 × 1,350 MWe Under construction Never commissioned Higashidori 1 Japan 1 1,385 MWe Under construction — * Shut down following the Fukushima accident (2011); NRA authorised restart of KK-6/7 in 2023.\n📌 Key Facts Direct cycle: core steam feeds the HP–LP turbine train directly, with no steam generator. The moisture separator–reheater (MSR) between HP and LP removes moisture and reheats steam using live steam. 11 extractions for feedwater heaters, fully optimised in the Thermoptim model presented in the book. Taiwan\u0026rsquo;s Lungmen was mothballed at ~80 % completion in 2014 following a political decision. 📐 SVG Flowsheets Figure 8.4.1 — Horizontal flowsheet Figure 8.4.1 — Stacked flowsheet 8.5 — RBMK · 1000 MWe USSR / Russia · Boiling-water graphite channel · Positive void coefficient\n⚡ Key Parameters Parameter Value Electric power 1,000 MWe Thermodynamic efficiency ~31 % Steam temperature 284 °C Steam pressure 65 bar Fuel pressure channels 1,693 🔬 Reactor Technology The RBMK (Reaktor Bolshoy Moshchnosti Kanalnyy, \u0026ldquo;high-power channel-type reactor\u0026rdquo;) is a Soviet boiling-water channel reactor moderated by graphite. Cooling water flows through 1,693 individual pressure tubes passing through a large graphite block. This architecture enables on-load refuelling (no shutdown required) but produces a positive void coefficient at low power, creating a dangerous instability. The thermodynamic cycle includes sealing steam evaporators (to remove impurities before the turbines) and several feedwater-heating stages. Fuel is lightly enriched UO₂ (2 %).\n🏭 Deployment History Plant Country Units Power First power Status Leningrad 1–4 USSR/Russia 4 4 × 1,000 MWe 1974–75/80–81 2019–2021 Chernobyl 1–4 USSR/Ukraine 4 4 × 925–1,000 MWe 1977–78/83–84 1991–2000 (Unit 4: accident 1986) Smolensk 1–3 Russia 3 3 × 1,000 MWe 1982–1990 In service Kursk 1–5 Russia 5 1,000 / 1,500 MWe 1977–2021 In service (1–2); under constr. (5) 📌 Key Facts The Chernobyl accident (26 April 1986, Unit 4) remains the most severe civil nuclear disaster in history (INES Level 7). Positive void coefficient (reactivity increases with steam voids) at low power and low load fraction: the instability responsible for the accident. Post-1986 modifications included redesigned control rods (faster insertion), fuel enrichment increased to 2.8 %, and tightened operating procedures. Several RBMK units remain in service in Russia (Leningrad, Smolensk, Kursk). The cycle uses sealing steam evaporators between the steam drum and the turbines to purge impurities. No RBMK has ever been built outside the USSR/Russia. 📐 SVG Flowsheets Figure 8.5.1 — Horizontal flowsheet Figure 8.5.1 — Stacked flowsheet 8.6 — VVER-1000 · 1000 MWe Russia / International · PWR (Russian variant) · Horizontal SG · Rosatom\n⚡ Key Parameters Parameter Value Electric power 950–1,000 MWe Thermodynamic efficiency ~33 % Steam temperature 278 °C Steam pressure 60 bar Steam generators 4 horizontal (PGV-1000) 🔬 Reactor Technology The VVER (Vodo-Vodyanoy Energeticheskiy Reaktor) is the Soviet/Russian pressurised water reactor. The VVER-1000 (model V-320 and successors) differs from Western PWRs in three key respects: hexagonal fuel assemblies rather than square, four horizontal steam generators (PGV-1000) instead of vertical ones, and a more compact primary-loop configuration. The horizontal steam generators offer better transient response. The secondary circuit includes four to five feedwater heaters.\n🏭 Deployment History Plant Country Units Power First power Status Novovoronezh 5, Balakovo 1–4, etc. Russia ~18 950–1,000 MWe 1980 → In service Zaporizhzhia 1–6 Ukraine 6 6 × 950 MWe 1985–1995 In service (Russian mil. control since 2022) Temelín 1–2 Czech Republic 2 2 × 1,000 MWe 2002/03 In service Kudankulam 1–2 India 2 2 × 917 MWe 2013/16 In service Akkuyu 1–4 (VVER-1200) Turkey 4 4 × 1,114 MWe 2028 → Under construction 📌 Key Facts Most widely deployed non-Western PWR design: ~50 VVER-1000 units in service worldwide as of 2024. Zaporizhzhia is the largest nuclear plant in Europe (6 × 950 MWe); has been under Russian military control since March 2022. The successor VVER-1200 (V-491) reaches 1,114–1,200 MWe with passive safety systems (Gen III+). Horizontal PGV-1000 steam generators: large heat-exchange area and distinct thermodynamic transient behaviour. Hexagonal fuel assemblies: 312 assemblies (vs. ~193 for an equivalent-power Western PWR). 📐 SVG Flowsheets Figure 8.6.1 — Horizontal flowsheet Figure 8.6.1 — Stacked flowsheet 8.7 — CANDU Pickering · 550 MWe Canada · PHWR · Heavy water · Natural uranium · On-load refuelling\n⚡ Key Parameters Parameter Value Electric power 515–540 MWe Thermodynamic efficiency ~30 % Steam temperature 260 °C Steam pressure 45 bar Fuel Natural uranium (0.7 % ²³⁵U) 🔬 Reactor Technology The CANDU (Canadian Deuterium Uranium) reactor uses heavy water (D₂O) as both moderator (in the calandria) and coolant (in pressure tubes). The excellent moderation provided by heavy water allows the use of natural uranium (UO₂) without enrichment — the reactor\u0026rsquo;s main strategic advantage. On-load refuelling is also possible (no outage required). Low steam conditions (~260 °C, 45 bar), compared with PWRs, yield a lower thermal efficiency (~30 %). The Pickering cycle includes 4 feedwater heaters.\n🏭 Deployment History Plant Country Units Power First power Status Pickering A \u0026amp; B (1–8) Canada (Ontario) 8 4 × 515 + 4 × 540 MWe 1971–1986 Planned shutdown during the mid-2020s Bruce A \u0026amp; B (1–8) Canada (Ontario) 8 ~740–800 MWe/unit 1977–1987 In service Darlington 1–4 Canada (Ontario) 4 4 × 878 MWe 1990–1993 In service (refurbishment 2016–2026) Wolsong 1–4 South Korea 4 679–700 MWe/unit 1983–1999 Partially in service Rajasthan (RAPS) 1–6 India 6 100–202 MWe/unit 1972–2009 In service Qinshan III 1–2 China 2 2 × 677 MWe 2002/03 In service 📌 Key Facts Key advantage: natural uranium fuel — no enrichment required, simplified fuel cycle. On-load refuelling: no annual shutdown for refuelling, high operational availability. Fuel flexibility: CANDU can burn thorium, depleted uranium, or MOX fuel. Pickering A (units 1–4): first commercial CANDU units (1971); shut down in 2024. Pickering B (units 5–8) remains in service (planned shutdown: mid-2020s). Darlington: four units undergoing major refurbishment for an additional 30 years of operation. ~50 CANDU/PHWR units in service worldwide (Canada, India, South Korea, China, Romania, Pakistan, Argentina). 📐 SVG Flowsheets Figure 8.7.1 — Horizontal flowsheet Figure 8.7.1 — Stacked flowsheet 8.8 — Superphénix · 1175 MWe France · Sodium-cooled Fast Reactor (SFR) · Pool-type · European consortium\n⚡ Key Parameters Parameter Value Electric power 1,175 MWe Thermodynamic efficiency ~40 % Steam temperature 487 °C Steam pressure 177 bar Primary sodium temperature 545 °C (max) 🔬 Reactor Technology Superphénix (SPX) was the most powerful sodium-cooled fast neutron reactor ever built. It uses liquid sodium as coolant without a moderator, giving a fast neutron spectrum. The architecture is pool-type: intermediate sodium–sodium heat exchangers and primary pumps are submerged in the large primary sodium pool (~3,300 t). Secondary sodium feeds the steam generators, which produce steam at high temperature (487 °C), yielding a high thermodynamic efficiency (~40 %). The cycle includes superheating and reheating stages.\n🏭 Deployment History Plant Country Units Power First power Status Creys-Malville (Isère) France 1 1,175 MWe 1986 (criticality 1985) Shut down 1997 (government decree) 📌 Key Facts The most powerful SFR ever built and operated: 1,175 MWe / 3,000 MWth. Built by a European consortium: EDF (51 %), ENEL (Italy, 33 %), SBK (Germany/Belgium/Netherlands, 16 %). Low lifetime availability (~14 %) due to repeated incidents (sodium leaks, sodium contamination) and political opposition. Shut down in 1998 by the Jospin government (official decree: December 1997), despite a technically favourable independent review. Steam at 487 °C / 177 bar: highly efficient steam cycle, comparable to the best conventional thermal power plants. Successor ASTRID (1,500 MWe) was abandoned in 2019; France is now relaunching its fast-reactor programme. 📐 SVG Flowsheets Figure 8.8.1 — Horizontal flowsheet Figure 8.8.1 — Stacked flowsheet 8.9 — HTR-PM · 200 MWe (model) China · High Temperature gas-cooled Reactor · Pebble-bed · TRISO fuel\n⚡ Key Parameters Parameter Value Electric power 200 MWe (2 reactors + 1 turbine) Thermodynamic efficiency 33.76 % Helium outlet temperature 750 °C Helium pressure 70 bar Steam temperature 566 °C Steam pressure 138 bar 🔬 Reactor Technology The HTR-PM (High Temperature Reactor — Pebble-bed Module) is a Chinese high-temperature helium-cooled, graphite-moderated reactor. The fuel takes the form of graphite pebbles (6 cm diameter) containing TRISO-coated fuel particles (multi-layer ceramic coating). The Shidao Bay plant pairs two 250 MWth reactors with a single shared steam turbine. Helium at 750 °C feeds a steam generator producing steam at 566 °C / 138 bar, giving a comparatively high thermodynamic efficiency for a graphite-moderated reactor.\n🏭 Deployment History Plant Country Configuration Power First power Status Shidao Bay (Rongcheng, Shandong) China 2 reactors + 1 turbine 200 MWe 2021 (criticality) / 2023 (grid) In service 📌 Key Facts First commercial HTR power plant in the world (2021–2023), at Shidao Bay, Shandong, China. TRISO pebble fuel: inherent containment — no core meltdown possible by design. Two HTR-PM250 reactors (250 MWth each) feed a single 200 MWe turbine. The achieved efficiency (33.76 %) falls short of the 40 % design target; an HTR-PM600 variant is under study. Helium outlet temperature (750 °C) enables high-temperature industrial heat applications (e.g., hydrogen production). The HTR-PM600 concept (6 × 250 MWth modules for 600 MWe) is under active study in China. The Shindao Bay Operating Data Very little information is publicly available about the HTR-PM secondary circuit. The Shindao Bay model presented here was constructed from data visible in Figure 5 of Dong et al. (2025), which shows the Human-Machine Interface (HMI) of the plant\u0026rsquo;s coordinated control system. This operational dashboard displays helium, steam and feedwater temperatures, core power, electrical output, efficiency, power level, and mass flow rates.\nNote: this model has not been validated by the original authors. Despite several requests, it has proven impossible to obtain direct information on the secondary circuit. The extraction pressures and flow rates were assumed; a polytropic efficiency of 70 % was applied to all turbine stages — the value that alone reproduces the announced electrical output of 64 MWe.\nThe discrepancies are significant. The plant was operating at approximately 80 % of rated power, which partially explains the reduced performance.\nWe provide here the two models, the first corresponding to the available experimental data, and the second to the nominal performance.\n📐 SVG Flowsheets Figure 8.9.1 — Horizontal flowsheet\nFigure 8.9.1 — Stacked flowsheet\nHTR-PM nominal flowsheet\n8.10 — Canadian SCWR · 1250 MWe (Concept) Canada · Supercritical Water-cooled Reactor · Generation IV · GIF concept\nWarning\rConceptual design only — This reactor is at the conceptual design stage (TRL ~3–4). No industrial prototype has been built to date. It is the only conceptual design in Chapter 8 that has not yet been built.\n⚡ Key Parameters Parameter Value Electric power 1,250 MWe Thermodynamic efficiency about 48 % Core outlet temperature 625 °C Primary pressure 250 bar Fuel Enriched UO₂ + Th 🔬 Reactor Technology The Canadian SCWR is a Generation IV supercritical water-cooled reactor concept. The coolant is raised above the critical point of water (374 °C, 221 bar) — to 625 °C / 250 bar — which gives it exceptional thermodynamic properties (no phase change, intermediate density). As in a BWR, the cycle is direct: water from the core feeds the turbine directly, with no steam generator. The theoretical efficiency is remarkably high (~48.73 %), rivalling the best combined-cycle gas plants. Moderation is provided by heavy water (calandria) or graphite depending on the variant. The supercritical Rankine cycle includes feedwater heaters and reheating.\n🏭 Status Item Details Conceptual design Studies ongoing since ~2010; no prototype scheduled before 2040+ TRL ~3–4 Programme GIF (Generation IV International Forum) — one of six priority concepts 📌 Key Facts Generation IV reactor: selected by the Generation IV International Forum (GIF) as one of six priority concepts. Projected thermal efficiency: 48 % — the highest of all concepts studied in the book. Direct cycle without a steam generator: supercritical water from the core feeds the turbine directly. No liquid–vapour phase transition: supercritical water is a single-phase fluid, eliminating the moisture separator. Compatible with thorium/uranium fuel: potential for breeding in a thermal spectrum. Open questions remain regarding cladding materials (e.g., zirconium alloys) at 625 °C in supercritical water (current TRL: ~3–4). 📐 SVG Flowsheets Figure 8.10.1 — Horizontal flowsheet Figure 8.10.1 — Stacked flowsheet 8.11 — EPR Flamanville 3 · 1650 MWe France / International · PWR Generation III+ · Framatome / EDF\n⚡ Key Parameters Parameter Value Net electric power 1,630–1,650 MWe Thermodynamic efficiency ~39 % Steam temperature 294 °C Steam pressure 78 bar Feedwater heaters 7 (4 LP + deaerator + 2 HP) Steam generators 4 🔬 Reactor Technology The EPR (Evolutionary Power Reactor) is a Generation III+ pressurised water reactor developed by Framatome and EDF. It differs from earlier French PWR series (900/1300/N4) in four main respects: very high unit power (~1,650 MWe), redundant and diversified safety systems (four 100 %-capacity safety trains), a core melt localisation device (\u0026ldquo;core catcher\u0026rdquo;), and a double reinforced-concrete containment. The secondary circuit, fed by four steam generators, includes 8 feedwater heaters. The book presents full off-design modelling (30–100 % load) with external controller — a world first for the EPR.\n🏭 Deployment History Plant Country Units Power First power Status Flamanville 3 France 1 1,630 MWe 2024 (criticality) / 2025 (commercial) In service Olkiluoto 3 Finland 1 1,600 MWe 2022 (criticality) / 2023 (commercial) In service Taishan 1 \u0026amp; 2 China 2 2 × 1,660 MWe 2018/19 In service Hinkley Point C 1 \u0026amp; 2 UK 2 2 × 1,630 MWe Under construction 2029–2031 (est.) Sizewell C 1 \u0026amp; 2 UK 2 2 × 1,630 MWe Approved 2023 2035+ (est.) 📌 Key Facts Flamanville 3: first criticality in 2024, commercial operation expected in 2026, after 17 years of construction. Olkiluoto 3 (Finland): commercial operation since May 2023, 13 years behind its original 2009 schedule. Taishan 1 \u0026amp; 2 (China): EPRs in continuous commercial service; Taishan 1 was temporarily shut down in 2021 due to fuel-cladding defects (corrosion issues); restarted in 2022. Record unit power among PWRs: ~1,650 MWe gross / ~1,600 MWe net. Book innovation: first published off-design modelling (30–100 % load) of the EPR secondary cycle. 📐 SVG Flowsheets Figure 5.9.16 — Horizontal flowsheet at 100 % load Figure 5.9.16 — Stacked flowsheet at 100 % load How to cite this fact sheet:\nFor the online version: Gicquel, R. (2026). Case Studies — Reactor Fact Sheets and Flowsheets. s4e2.com. Accessed on [Date].\nFor the book version: Gicquel, R. (2026). Engineering Thermodynamics: Advanced Modeling of Energy Systems and Nuclear Cycles (Volume 2). Routledge/Taylor \u0026amp; Francis Group. ISBN: 9781032997872.\n","title":"Case Studies — Reactor Fact Sheets and Flowsheets","uri":"https://server.s4e2.com/crc/tcnpp/resources/svg/"},{"content":"📈 Interactive Thermodynamic Cycle Diagrams These three interactive tools plot the thermodynamic states of nuclear reactor cycles on classic thermodynamic diagrams. Any combination of reactors can be displayed simultaneously — select one or more cycles from the list and click Load Selected Cycles. Hovering over a point shows its label and coordinates. The saturation curve can be toggled on or off. Plotly\u0026rsquo;s built-in tools allow zoom, pan, and export to PNG.\nHow to read these diagrams in context: the reactor fact sheets and flowsheets show how each cycle is constructed. The exergy balances show where the losses occur. These diagrams show how the thermodynamic states distribute relative to the saturation curve — which turbine stages operate in wet steam, how much superheat is available, and how the feedwater heating chain raises feedwater temperature before the steam generator.\nTemperature–Entropy Diagram (T-S) The T-S diagram is the most direct representation of cycle quality. The area enclosed by the cycle is proportional to net work. Irreversibilities appear as deviations from ideal isentropic processes. The WCR family clusters compactly in the lower region; high-temperature cycles (SCWR, AGR, HTR-PM) extend upward.\n💡 For better zoom control and full-screen viewing, open the T-S diagram directly.\nEnthalpy–Pressure Diagram (h-P) The h-P diagram shows the full pressure range on a logarithmic scale — the pressure architecture of each cycle and turbine extraction levels. The supercritical SCWR (~250 bar) sits clearly above the saturation dome. The NuScale US460 condenser at 0.038 bar is visible at the extreme bottom.\n💡 For better zoom control and full-screen viewing, open the h-P diagram directly.\nMollier Diagram (h-S) The Mollier (enthalpy–entropy) diagram is the standard tool for turbine engineers. The slope of the expansion lines indicates the isentropic efficiency of each turbine stage. The position relative to the saturation curve shows steam quality throughout the expansion — including the wet steam region of the NuScale US460 that explains the high Turbine 4 irreversibilities discussed in the exergy balance analysis.\n💡 For better zoom control and full-screen viewing, open the Mollier diagram directly.\nAvailable Cycles French PWR family — EPR Flamanville\nCycle ID Description Flamanville_R_100% simplified WCR model Flamanville 100 % — simplified WCR model (Nuscle) Flamanville_R_90% simplified WCR model Flamanville 90 % — simplified WCR model (Nuscle) Flamanville_R_70% simplified WCR model Flamanville 70 % — simplified WCR model (Nuscle) Flamanville_R_50% simplified WCR model Flamanville 50 % — simplified WCR model (Nuscle) Flamanville_R_30% simplified WCR model Flamanville 30 % — simplified WCR model (Nuscle) Flamanville 100% R ASN security report Flamanville 100 % — ASN safety report data Flamanville 90% R ASN security report Flamanville 90 % — ASN safety report data Flamanville 70% R ASN security report Flamanville 70 % — ASN safety report data Flamanville 50% R ASN security report Flamanville 50 % — ASN safety report data Flamanville 30% R ASN security report Flamanville 30 % — ASN safety report data N4 French PWR N4 French PWR N4 French PWR detailed cycle N4 French PWR — detailed cycle CP0 French PWR CP0 French PWR CP2 French PWR CP2 French PWR Gas-cooled reactors\nCycle ID Description Hartlepoole AGR Cycle AGR Hartlepool TornessExtr AGR Torness HTR-PM Shidao Bay HTR-PM — Shidao Bay operating data Water-cooled reactors (WCR)\nCycle ID Description VVER K-1000-60/1500-2 VVER-1000 (K-1000-60/1500-2) VVER_70 VVER-70 RBMK_K-1000-65-3000 RBMK-1000 (K-1000-65-3000) Candu CANDU Pickering ABWR ABWR NuScale SMR NuScale SMR Fast and advanced reactors\nCycle ID Description Superphenix French SFR Superphénix (SFR) Canadian SCWR Canadian SCWR \u0026ldquo;Simplified WCR model\u0026rdquo; = Nuscle model. See the Nuscle section for an explanation of the differences between Nuscle simplified models and detailed Thermoptim models, and how to interpret them.\nParticularly Instructive Comparisons A few combinations that reveal thermodynamic contrasts clearly:\nLoad pattern sensitivity (Flamanville EPR): load Flamanville_R_30% simplified WCR model through Flamanville_R_100% simplified WCR model together — the five operating points trace a family of cycles that shrink toward the lower left as power decreases. The feedwater heating line progressively shortens.\nTwo generations of VVER: VVER_70 + VVER K-1000-60/1500-2 — saturated steam + separator vs. superheated steam + MSR. The contrast in steam conditions at HP turbine inlet is immediately visible on the Mollier diagram.\nGas-cooled vs. water-cooled: Hartlepoole AGR Cycle + N4 French PWR — the AGR cycle extends to 541 °C / 170 bar, far above the EPR. On the T-S diagram the temperature difference between the two families is striking.\nSMR at low power: NuScale SMR — the most compact cycle in the collection. On the Mollier diagram, the LP expansion clearly crosses into the wet steam region.\nSimplified vs. detailed (EPR): Flamanville_R_100% simplified WCR model + N4 French PWR detailed cycle — the Nuscle simplified model vs. the full detailed N4 cycle. On the T-S diagram, the feedwater heating steps are more numerous and smaller in the detailed model.\nReading the Three Diagrams Together The three diagrams are most informative when used in sequence:\nT-S → identifies temperature conditions and regenerative heating extent h-P → reveals the pressure architecture and extraction points h-S (Mollier) → evaluates turbine stage quality and wet steam extent For each reactor, the detailed exergy balance quantifies the irreversibilities that these diagrams make geometrically visible.\nThermodynamic cycle data: Thermoptim project files. Diagrams generated with Plotly. Models for AGR Hartlepool, Torness, HTR-PM Shidao Bay, VVER-70, and the full Flamanville load range are available exclusively on this companion website.\n","title":"Interactive Thermodynamic Cycle Diagrams","uri":"https://server.s4e2.com/crc/tcnpp/resources/cycles-diagrams/"},{"content":"HTR-PM — Exergy Analysis: Design vs Operating Data The HTR-PM (High Temperature Reactor — Pebble-bed Module) is a helium-cooled reactor using TRISO pebble fuel. Two reactor modules supply steam to a single turbine. The Shindao Bay plant (Shandong province, China) is the first industrial-scale deployment of this concept, commissioned in 2021.\nThis page presents two exergy balances for the same reactor: the nominal design model (turbines at design efficiency) and a Shindao Bay model calibrated on operating data published by Dong et al. (2025). The comparison illustrates how an exergy balance can diagnose the source of performance gaps in a real plant.\nThe Shindao Bay Operating Data Very little information is publicly available about the HTR-PM secondary circuit. The Shindao Bay model presented here was constructed from data visible in Figure 5 of Dong et al. (2025), which shows the Human-Machine Interface (HMI) of the plant\u0026rsquo;s coordinated control system. This operational dashboard displays helium, steam and feedwater temperatures, core power, electrical output, efficiency, power level, and mass flow rates.\nNote: this model has not been validated by the original authors. Despite several requests, it has proven impossible to obtain direct information on the secondary circuit. The extraction pressures and flow rates were assumed; a polytropic efficiency of 70 % was applied to all turbine stages — the value that alone reproduces the announced electrical output of 64 MWe.\nThe comparison between announced design values and HMI readings is striking:\nParameter Design Shindao Bay (HMI) Relative difference T helium (°C) 750 563.7 −24.8 % Core power (MWth) 250 197.5 −21.0 % Electric power (MWe) 105 64 −39.1 % T steam (°C) 566 519.9 −8.1 % Efficiency (%) 40 34.1 −14.7 % Power level (%) 100 79.5 −20.5 % Source: Dong, Z., Zhang, Z., Dong, Y. et al. Testing the feasibility of multi-modular design in an HTR-PM nuclear plant. Nat Commun 16, 2778 (2025). https://doi.org/10.1038/s41467-025-58194-7\nThe discrepancies are significant. The plant was operating at approximately 80 % of rated power, which partially explains the reduced performance — but the electrical output shortfall (−39 %) is disproportionate relative to the thermal power reduction (−21 %), pointing to turbine efficiency as the primary driver.\nCycle Summary Nominal design Shindao Bay Thermal power (MWth) 190.8 198.9 Electric power (MWe) ~79 ~68 η energy (%) 41.3 % 34.2 % η Xh (%) 60.9 % 50.4 % The steam generator receives 72.7 kg/s of feedwater at 125 bar and 159.8 °C (Shindao Bay conditions) and delivers steam at 110.8 bar and 519.9 °C. The feedwater train comprises three LP heaters (LPH1–3) and one HP heater (HPH4).\nExergy Balance Comparison Component Nominal design Shindao Bay Change Core (Tk = 624 °C) 43.5 % 35.8 % −7.7 pts Steam generator He→steam 20.6 % 19.1 % −1.5 pts Turbines T1–T6 18.9 % 30.5 % +11.6 pts Condenser (Tk = 15 °C) 10.4 % 8.8 % −1.6 pts FWH (HPH4 + LPH1–3) 5.3 % 4.6 % −0.7 pts What the Balance Reveals The exergy balance localises the performance gap with precision: the turbines alone account for the entire difference, increasing from 18.9 % to 30.5 % of total irreversibilities (+11.6 pts). The source (core + SG) and condenser contributions are only modestly affected.\nThis is exactly the diagnostic function of an exergy balance. A purely energetic analysis would show that η energy falls from 41.3 % to 34.2 % — a 7.1-point drop — but would not identify where the losses originate. The exergy balance points directly to the turbines.\nThe individual turbine efficiencies in the Shindao Bay model tell the same story:\nStage Nominal η Shindao Bay η Turbine 1 0.931 0.839 Turbine 2 0.914 0.812 Turbine 3 0.894 0.779 Turbine 4 0.878 0.744 Turbine 5 0.852 0.717 Turbine 6 0.835 0.691 The degradation is progressive from stage 1 to stage 6 — the LP stages are proportionally the most affected. This pattern is consistent with operation at partial load (~80 %), where the steam conditions at each stage inlet deviate increasingly from the design point as expansion proceeds.\nWhether the low turbine efficiencies reflect the partial-load operating point, teething issues specific to a first-of-a-kind prototype, or both, cannot be determined from the available data alone. The exergy balance does not answer this question — but it identifies the turbines as the only component worth investigating.\nNote on the HTR-PM Steam Generator The HTR-PM steam generator is a helical-coil once-through design integrated within the reactor vessel. It is modelled here as a single unit receiving helium at the design (nominal) or measured (Shindao Bay) temperature and delivering superheated steam. The SG contribution to total irreversibilities (19–21 %) reflects the gas→steam heat exchange penalty discussed in the AGR Hartlepool analysis.\nUnlike gas-cooled reactors with separate SG sections (economiser, evaporator, superheater, reheater), the helical-coil SG cannot be decomposed into sub-components in the Thermoptim model without additional geometric data. The SG irreversibility is therefore reported as a single value.\nReferences Dong, Z., Zhang, Z., Dong, Y. et al. Testing the feasibility of multi-modular design in an HTR-PM nuclear plant. Nat Commun 16, 2778 (2025). https://doi.org/10.1038/s41467-025-58194-7 Chen, F., Han, Z. Steady-state thermal fluids analysis for the HTR-PM equilibrium core. International Journal of Advanced Nuclear Reactor Design and Technology 3, 11–17 (2021). https://doi.org/10.1016/j.jandt.2021.04.001 Thermoptim models: HTR_PM_2023_trad_OK.prj (nominal) and HTR_PM_2023_68MW.prj (Shindao Bay). Exergy balances processed with ExerBalanceHX.\n","title":"HTR-PM — Exergy Analysis: Design vs Shindao Bay","uri":"https://server.s4e2.com/crc/tcnpp/resources/exergy/htr-pm-exergy/"},{"content":"Flowsheets of the Flamanville EPR The results presented in this case study derive from detailed data provided by EDF to the French Nuclear Safety Authority (ASN) in support of the commissioning authorization for the Flamanville EPR power plant.\nAlthough highly insightful, this dataset introduces several complexities, as it is subject to various interpretations. Specifically, strictly adhering to the diagram values appears to underestimate the generated power in some instances. Attempting to reconcile these power values—while holding parameters like feedwater temperature constant—requires adjusting the polytropic expansion efficiency as well as the extraction rates.\nIn the flowsheets provided below, the former option was chosen. As a result, the power values differ slightly from the official figures.\nFlamanville 3 EPR 100 %\nFlamanville 3 EPR 90 %\nFlamanville 3 EPR 70 %\nFlamanville 3 EPR 50 %\nFlamanville 3 EPR 30 %\n","title":"Flamanville EPR Flowsheets","uri":"https://server.s4e2.com/crc/tcnpp/resources/epr/"},{"content":"Stodola\u0026rsquo;s law In its most common definition, Stodola\u0026rsquo;s law, or the cone rule, expresses, for a steam turbine operating at constant speed, a nearly quadratic relationship between mass flow rate and upstream and downstream pressures, which results in an almost linear dependence between flow rate and inlet pressure for a fixed downstream pressure. It is often used in a simplified form that relates the reduced flow to the square root of the difference of the squares of the pressure roots, and serves as the natural behavior law of condensing turbines in off-design operation.\nAs we will see, this definition is only valid when it can be assumed that the working fluid can be treated as an ideal gas.\nIn this case, and if no specific assumptions are made about the relationship between upstream and downstream pressures, the expression of Stodola\u0026rsquo;s law is as follows:\n$$ \\frac{{T_{\\text{in}}} \\dot{m}^2}{K^2} = P_{\\text{in}}^2 - P_{\\text{out}}^2 \\tag{9.4.11}$$ Quadratic Stodola Equation (ideal gas) In this expression, the values with the \u0026lsquo;in\u0026rsquo; subscript relate to the turbine\u0026rsquo;s inlet, and those with the \u0026lsquo;out\u0026rsquo; subscript to its outlet. K is called the Stodola constant.\nIf we assume that the downstream pressure is negligible compared to the upstream pressure, it simplifies and becomes:\n$$ \\frac{\\dot{m} \\sqrt{T_{\\text{in}}}}{P_{\\text{in}}} = \\text{Const} \\tag{9.4.12} $$ Simplified Stodola Equation (ideal gas) It can be shown that, in the general case, it can be expressed as follows:\n$$ \\dot{m} \\sqrt{\\frac{(k+1)v_{\\text{in}}}{k P_{\\text{in}}} } = K_0 \\sqrt{1 - \\left[\\frac{P_{\\text{out}}}{P_{\\text{in}}}\\right]^{(k+1)/k}} \\tag{9.4.14} $$ Generalized Stodola equation The main differences are that if k is the coefficient of the law passing through the upstream and downstream points (which has no reason to be a polytropic):\nthe temperature disappears from the square root on the left-hand side of the equation\nthe exponent of the pressure ratio that was 2 is replaced by the term (k+1)/k, which depends on the properties of the fluid and therefore varies according to the turbine\u0026rsquo;s inlet and outlet conditions\nthe square root of the inverse of this term multiplies Stodola\u0026rsquo;s \u0026lsquo;constant\u0026rsquo;, which therefore also varies depending on the operating conditions of the turbine.\nThis expression is much more complex than the simplified Stodola law usually used, which corresponds to equation (9.4.12).\n","title":"Stodola Law","uri":"https://server.s4e2.com/crc/tcnpp/resources/stodola/"},{"content":"��-�-�-� �t�i�t�l�e�:� �T�e�s�t� �-�-�-�\r� �\n","title":"","uri":"https://server.s4e2.com/crc/tcnpp/test/"},{"content":"","title":"Search","uri":"https://server.s4e2.com/crc/tcnpp/search/"}]