Annals of Nuclear Energy最新文献

{"title":"Transient simulation of the USNC Pylon using a rapid multiphysics model","authors":"Zane G. Tucker ,&nbsp;Todd S. Palmer","doi":"10.1016/j.anucene.2025.111367","DOIUrl":"10.1016/j.anucene.2025.111367","url":null,"abstract":"<div><div>A multiphysics model of the Pylon microreactor, currently under development by Ultra Safe Nuclear Corporation, has been designed and implemented for the purpose of later constructing and testing an autonomous control system. This model is implemented in a custom simulation program written in Fortran 2003, which uses a Runge–Kutta integrator to solve the necessary differential equations. Representative “modules” have been constructed for the reactor physics, Brayton cycle turbogenerator, and radiative ultimate heat sink in a replaceable manner. This work describes the governing equations of this model, the assumptions that lead to these equations, and software validation efforts. Simulations of two representative power-changing transients are described and analyzed.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"218 ","pages":"Article 111367"},"PeriodicalIF":1.9,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Advanced-Technology-Fuel options in soluble boron-free Small Modular Reactors","authors":"A. de Lara ,&nbsp;X. Ha Nguyen ,&nbsp;P. Van Uffelen ,&nbsp;E. Shwageraus","doi":"10.1016/j.anucene.2025.111355","DOIUrl":"10.1016/j.anucene.2025.111355","url":null,"abstract":"<div><div>Water-cooled Small Modular Reactors (SMRs) have gained significant attention as they could be modularised, standardised, and factory-fabricated to reduce capital cost and improve passive safety. However, SMRs often come with lower power density, which makes them less competitive with commercial LWRs. To enhance SMRs’ operation margin, deployment of the Advanced Technology Fuels (ATFs) can be beneficial. Therefore, this study examines the application of short-term ATF solutions in a soluble boron-free (SBF) SMR design inspired by Rolls Royce’s SMR. The analysis integrates neutronic and thermo-mechanical performance evaluations by means of advanced nuclear modelling tools: WIMS, PANTHER, and TRANSURANUS. The study focuses on core design parameters, including reactivity control, power distribution, shutdown margin and other design limits. In addition, fuel performance was investigated in terms of fission gas release (FGR), fuel temperature and cladding strain. The neutronic analyses suggest that the maximum peaking factors of SBF cores are about 15% higher than those of soluble boron-controlled cores. The deployment of FeCrAl cladding, Cr coating of conventional Zricaloy cladding and Cr doping of UO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> fuel have a minor impact on both total power peaking and axial offset. On the other hand, the thermo-mechanical results show that Cr-doped fuel and Cr-coated cladding significantly improve fuel performance, reducing FGR and fuel temperature, while FeCrAl cladding offers limited benefits under the evaluated conditions. Comparative analyses indicate that SBF cores, while operationally viable, present unique design challenges due to a higher power peaking and associated thermal fluctuations, necessitating optimisation of control rod strategies and fuel assembly design. The findings demonstrate the feasibility of incorporating ATFs in SBF SMRs, aligning with European green taxonomy criteria for sustainable nuclear development. This study highlights the potential of combined Cr-doped fuel and Cr-coated cladding as a promising strategy to enhance performance in advanced nuclear reactor designs.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"218 ","pages":"Article 111355"},"PeriodicalIF":1.9,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics of wall bubbles in flash evaporation systems: Heterogeneous expansion and microlayer development","authors":"Qifan Wang ,&nbsp;Junren Hou ,&nbsp;Shanfang Huang ,&nbsp;Fangbei Chen ,&nbsp;Minyun Liu ,&nbsp;Ruohan Zheng ,&nbsp;Yanping Huang ,&nbsp;Lie Quan ,&nbsp;Houjun Gong ,&nbsp;Yu Tang","doi":"10.1016/j.anucene.2025.111371","DOIUrl":"10.1016/j.anucene.2025.111371","url":null,"abstract":"<div><div>This study employs the Lattice Boltzmann method to investigate the expansion dynamics of a wall-attached bubble in a flashing chamber. The computational framework is validated against thermodynamic consistency and the Young-Laplace law. Results reveal that bubble expansion follows the Rayleigh-Plesset equation. On hydrophilic surfaces, the contact line movement rate is positively correlated with the contact angle. In contrast, hydrophobic surfaces exhibit an extremely rapid contact line movement rate near a contact angle of <span><math><mrow><msup><mn>120</mn><mo>°</mo></msup></mrow></math></span>, due to coupled pressure-driven inertial and liquid jet entrance forces. A liquid microlayer forms on hydrophilic surfaces but is absent on hydrophobic ones, with its thickness stabilizing after four expansion cycles, following a power-law relationship with lateral spatial variables and an inverse-power-law relationship with the Reynolds number. The contact angle significantly impacts the power-law index. These findings elucidate how inertial, viscous, and capillary forces govern bubble dynamics, providing insights into flash evaporation mechanism in nuclear engineering.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"218 ","pages":"Article 111371"},"PeriodicalIF":1.9,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study on characteristics of hydrogen deflagration and detonation in the combustion tube","authors":"Bo Liu,&nbsp;Shihao Wu,&nbsp;Xin Shi,&nbsp;Yapei Zhang,&nbsp;Yingwei Wu","doi":"10.1016/j.anucene.2025.111382","DOIUrl":"10.1016/j.anucene.2025.111382","url":null,"abstract":"<div><div>In severe accidents for a nuclear power plant, the zirconium-water reaction may produce a huge amount of hydrogen. The hydrogen combustion and explosion produce heavy pressure and temperature loads, which may cause equipment damage and even containment failure. Based on previous experiments on detonation in the tube, this study established numerical models of hydrogen deflagration and detonation in the tube using the FLUENT software. The process of flame acceleration and onset of detonation was accurately simulated. Calculation and experimental results show that the detonation velocity increases with the increase of stoichiometric ratio, and the peak temperature and pressure reach the maximum when stoichiometric ratio is 1.2. The detonation velocity, peak temperature and pressure are positively correlated with the initial pressure. The verified models can be used to predict hydrogen explosion phenomenon and evaluate its consequences in pressurized water reactor containment under severe accidents.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"217 ","pages":"Article 111382"},"PeriodicalIF":1.9,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Benchmarking a point reactor kinetics method with delayed neutron precursors transport using data from molten salt reactor experiment","authors":"Mohamed Elhareef,&nbsp;Zeyun Wu","doi":"10.1016/j.anucene.2025.111366","DOIUrl":"10.1016/j.anucene.2025.111366","url":null,"abstract":"<div><div>A consistent point reactor kinetics (PRK) model-based method was developed for analyzing the transient behavior of circulating fuel systems such as molten salt reactors (MSRs). The consistent PRK model was derived based on the factorization approach and was exclusively used for calculating neutron flux amplitude, while the delayed neutron precursors were treated as part of the thermal-hydraulics model to better count for the spatial effects of species transport phenomena occurring in the circulating fuel systems. The mathematical models developed in the method was implemented using COMSOL Multiphysics platform featuring neutronics, thermal-fluidics, and species transport. An efficient reactivity feedback model is established within the platform to provide thermal feedback from the system-level thermal-hydraulics model to the PRK based neutronics model. The results produced by the computational models were validated against Molten Salt Reactor Experiment (MSRE) experimental data.</div><div>The developed models were first employed to examine MSRE responses at steady-state conditions, and then benchmarked with a couple of transient tests that took place during the MSRE ²³³U phase of operations: the reactivity insertion tests and the low power natural circulation test. In steady-state conditions, a parametric study examined the effects of flow rates on kinetics parameters and showed that delayed neutron fractions strongly correlated with flow rate, while prompt neutron generation time exhibited minor sensitivity. In reactivity insertion tests, different parameter sets were analyzed to assess the impact on reactor response, showing graphite temperature feedback has limited influence whereas fuel temperature feedback provides more impact. Additionally, the reactivity insertion rate has effect on power responses, especially at higher power levels. Also, the effect of circulating void fraction was addressed as a random process. In natural circulation test, the MSRE response to a stepwise increase of the heat rejection rate was tested. The flow in the primary loop was maintained by fuel density variations and the reactor power was controlled by the heat load through thermal feedback mechanisms. This transient is used to validate the heat transfer correlation and natural flow capabilities. All the results highlight the efficiency and accuracy of the developed consistent PRK method, validating its use in MSR-type advanced reactor safety analysis and design optimization.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"217 ","pages":"Article 111366"},"PeriodicalIF":1.9,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the transient flow and vortex structure evolution mechanism of reactor coolant pump under non-uniform inflow","authors":"Long Yun,&nbsp;Wu Zhenguo,&nbsp;Zhang Mingyu,&nbsp;Xu Yuan","doi":"10.1016/j.anucene.2025.111346","DOIUrl":"10.1016/j.anucene.2025.111346","url":null,"abstract":"<div><div>As the key equipment of the nuclear power plant, the performance of the reactor coolant pump (RCP) are directly related to the safe operation of the nuclear power plant. However, the non-uniform inflow affects the stable operation of RCP. In this article, the transient flow characteristics of the RCP under non-uniform inflow conditions are investigated by establishing a steam generator simulation equipment-reactor coolant pump (SGSE-RCP) coupling model for numerical simulation. The transient flow field inside the RCP under non-uniform inflow conditions is extracted. The <em>Q</em> criterion is used to extract and analyze the vortex structure distribution of the RCP under non-uniform inflow conditions. The influence mechanism of non-uniform inflow on the vortex structure inside the RCP is revealed. The research in this article deeply reveals the influence of non-uniform inflow on the flow of RCP, and provides support for further exploring the influence mechanism of non-uniform inflow on RCP.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"217 ","pages":"Article 111346"},"PeriodicalIF":1.9,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Barium-calcium-lead-borate glasses: A new extent optimization of gamma-ray shielding","authors":"Reda Abdel-Hameed ,&nbsp;Nagah Abourashed ,&nbsp;Ashraf Ashmawy ,&nbsp;Eshraqa Ali ,&nbsp;Bader Huwaimel ,&nbsp;M. Abdallah ,&nbsp;Ali Hydaya ,&nbsp;Esraa H. Abdel-Gawad ,&nbsp;Mohamed.Elsafi","doi":"10.1016/j.anucene.2025.111384","DOIUrl":"10.1016/j.anucene.2025.111384","url":null,"abstract":"<div><div>The mechanical and radiation shielding performance of lead-borate-based glass samples <span><math><mrow><mn>45</mn><msub><mi>B</mi><mn>2</mn></msub><msub><mi>O</mi><mn>3</mn></msub><mo>:</mo><mn>25</mn><mi>P</mi><mi>b</mi><mi>O</mi><mo>:</mo><mfenced><mrow><mn>25</mn><mo>-</mo><mi>x</mi></mrow></mfenced><mi>C</mi><mi>a</mi><mi>O</mi><mo>:</mo><mi>x</mi><mi>B</mi><mi>a</mi><mi>O</mi><mfenced><mrow><mi>x</mi><mo>=</mo><mrow><mn>5</mn><mo>,</mo><mn>10</mn><mo>,</mo><mn>15</mn></mrow><mo>&amp;</mo><mn>20</mn><mi>m</mi><mi>o</mi><mi>l</mi><mo>%</mo></mrow></mfenced></mrow></math></span> were evaluated<span><math><mo>.</mo></math></span> The density values range from <span><math><mrow><mn>4.510</mn><mi>g</mi><mo>.</mo><msup><mrow><mi>cm</mi></mrow><mrow><mo>-</mo><mn>3</mn></mrow></msup></mrow></math></span> for BPCB-5 to <span><math><mrow><mn>4.815</mn><mi>g</mi><mo>.</mo><msup><mrow><mi>cm</mi></mrow><mrow><mo>-</mo><mn>3</mn></mrow></msup></mrow></math></span> for BPCB-20. Makishima-Mackenzie’s theory was applied, and mechanical moduli were derived. The increase in BaO content made the microhardness, shear modulus, and Young’s modulus slightly decreased. Simultaneously, radiation shielding parameters were assessed within energies <span><math><mrow><mn>0.662</mn></mrow></math></span>, <span><math><mrow><mn>1.173</mn></mrow></math></span> and <span><math><mrow><mn>1.333</mn></mrow></math></span> <span><math><mrow><mi>MeV</mi></mrow></math></span>. The results of BPCB-20 sample surpasses all other samples in terms of radiation shielding capabilities. The half value layer at <span><math><mrow><mn>0.662</mn><mi>M</mi><mi>e</mi><mi>V</mi></mrow></math></span> were <span><math><mrow><mn>1.662</mn><mo>,</mo><mn>1.635</mn><mo>,</mo><mn>1.610</mn></mrow></math></span> and <span><math><mrow><mn>1.587</mn><mi>c</mi><mi>m</mi></mrow></math></span> for BPCB-5, BPCB-10, BPCB-15 and BPCB-20, respectively. The samples BPCB-5 and BPCB-20 have separate radiation shielding effectiveness measurements of <span><math><mrow><mn>56.585</mn></mrow></math></span> and <span><math><mrow><mn>58.262</mn><mo>%</mo></mrow></math></span> for <span><math><mrow><mn>20</mn><mi>m</mi><mi>m</mi></mrow></math></span> thickness of the sample. These glass samples are superior to commercial glass that is being adopted in the market such as RS-360, since the HVL for RS-360 at <span><math><mrow><mn>0.662</mn><mi>M</mi><mi>e</mi><mi>V</mi></mrow></math></span> is.<span><math><mrow><mn>2.166</mn><mi>c</mi><mi>m</mi><mo>.</mo></mrow></math></span></div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"217 ","pages":"Article 111384"},"PeriodicalIF":1.9,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143682651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting time-correlated leakage rates of double-sealed hatch under accident conditions in a nuclear power plant","authors":"Xiaoming Huang ,&nbsp;Lei He ,&nbsp;Ming Li ,&nbsp;Xing Fang ,&nbsp;Jiawei Wang ,&nbsp;Guoliang Xu","doi":"10.1016/j.anucene.2025.111354","DOIUrl":"10.1016/j.anucene.2025.111354","url":null,"abstract":"<div><div>A gaseous circuit model is proposed for predicting the time-correlated leakage rate of double-sealed structures used in the large diameter hatches, which are considered to be the most vulnerable parts of the containment systems. The core task of the model is the determination of the instantaneous dual O-ring flow resistance, deduced from existing interfacial leakage mechanisms and combined with the effect of large flange deflection. After validation by comparison with experimental measurements, the model is used to quantitatively investigate the leakage behavior of a double-sealed hatch under various air source excitations. It is found that, the leakage related parameters all vary exponentially with time under constant pressure excitation, with higher pressures corresponding to faster system stabilization rates. However, under a dynamic accident scenario, the leakage related parameters follow the internal pressure, and a significant lag in parasitic pressure and outer leakage can be observed during the pressure decay phase.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"217 ","pages":"Article 111354"},"PeriodicalIF":1.9,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reactor multi-physics internal coupling method based on STL unified dynamic mesh","authors":"Yungeng LI ,&nbsp;Qingquan PAN ,&nbsp;Xiaojing LIU","doi":"10.1016/j.anucene.2025.111377","DOIUrl":"10.1016/j.anucene.2025.111377","url":null,"abstract":"<div><div>The Monte Carlo method is widely used in reactor multi-physics analysis due to its superior accuracy. However, it faces geometry incompatibility with multi-physics software. Traditional coupling relies on external interfaces and approximates geometric deformation. This study develops a high-fidelity Monte Carlo multi-physics coupling method; it has the following characteristics: (1) internal coupling between multi-physics fields; (2) a unified mesh for all physical fields; (3) dynamic mesh capabilities for geometric deformations; (4) partition adaptive STL model. Based on the irradiation neutronics platform <strong>Light</strong>, we develop a multi-physics coupling module, <strong>LightMP</strong>. It is internally coupled with the Monte Carlo neutronics module <strong>LightMC</strong>. This integration realizes high-fidelity “Neutronic-Thermal-Mechanical” coupling within a unified dynamic mesh. We tested it on a single channel and a 3 × 3 bundle of PWR. The results agreed with the reference values, proving the accuracy and robustness of this method.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"217 ","pages":"Article 111377"},"PeriodicalIF":1.9,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adjoint-based path length stretching in a Woodcock framework with SIRS angular biasing","authors":"David Legrady,&nbsp;Marton Pukler,&nbsp;Gabor Tolnai","doi":"10.1016/j.anucene.2025.111255","DOIUrl":"10.1016/j.anucene.2025.111255","url":null,"abstract":"<div><div>The development of an adjoint-based path-stretching scheme within a non-analog Woodcock (delta-tracking) framework is predicated on zero-variance formalism. The derivation of an ideal cross-section stretching factor is possible from the incident and the outgoing adjoint collision densities. The incorporation of this bias into the virtual collision decision probability necessitates time-consuming oversampling (high sampling cross section) to achieve low variance. Conversely, a similar effect can be achieved by stretching the sampling cross section, which, however, results in a considerable increase in variance, even for minor discrepancies between the actual local and the sampling cross sections. To mitigate this, a combination of the two bias methods is necessary. Nevertheless, sensitivity to the difference between sampling and actual cross sections persists, which limits the maximum efficiency gain. To address this challenge, a Sampling Importance Resampling (SIRS) scheme was devised for angular biasing, as both transport and collision kernels necessitate biasing for a significant enhancement in efficiency. The efficacy of the algorithm is demonstrated through numerical examples for source-detector systems, employing realistic geometries and utilizing the GUARDYAN code.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"217 ","pages":"Article 111255"},"PeriodicalIF":1.9,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}