Annals of Nuclear Energy最新文献

{"title":"Natural radioactivity and radiological hazards in ultrapotassic rocks from the Central Pontides, Türkiye","authors":"Aydın Yıldırım ,&nbsp;Fatma Gülmez","doi":"10.1016/j.anucene.2025.111619","DOIUrl":"10.1016/j.anucene.2025.111619","url":null,"abstract":"<div><div>Primordial radionuclides (²²⁶Ra, ²³²Th, ⁴⁰K) are key contributors to natural radiation and tend to concentrate in specific lithologies in the Earth’s crust. This study investigates Upper Cretaceous ultrapotassic rocks from the Central Pontides in Türkiye, where increasing constructional and industrial activities raise concerns about radiological exposure and environmental health risks. Gamma spectrometry analysis of powdered rock samples reveals that ²²⁶Ra (10.0–53.6 Bq/kg) and ²³²Th (9.3–65 Bq/kg) generally fall below global averages, whereas ⁴⁰K reaches notably high levels (97–1940 Bq/kg). Elevated ⁴⁰K levels in trachytic, leucite-bearing, and lamprophyric rocks from Amasya, Tosya, and Kalecik, result in radiological hazard parameters exceeding recommended limits, despite relatively modest ²²⁶Ra and ²³²Th activities. Correlation analyses indicate moderate relationships between ²²⁶Ra and ²³²Th, but weak correlations with ⁴⁰K, suggesting post-magmatic processes possibly influenced these rocks. These findings underscore the importance of ultra- and high-potassic rocks as potential gamma radiation sources in areas where land use, construction, and dust or soil mobilization increase interactions with biological organisms. Continuous monitoring of potassium-40 pathways and the proper management strategies are critical to mitigate possible health risks associated with elevated radionuclide concentrations.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111619"},"PeriodicalIF":1.9,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144472030","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":"Decoding the environmental role of nuclear and renewable energy consumption: A time-frequency perspective","authors":"Tomiwa Sunday Adebayo ,&nbsp;Dilber Uzun Ozsahin ,&nbsp;Victoria Olushola Olanrewaju ,&nbsp;Berna Uzun","doi":"10.1016/j.anucene.2025.111660","DOIUrl":"10.1016/j.anucene.2025.111660","url":null,"abstract":"<div><div>Harnessing nuclear and renewable energy offers a powerful pathway to slash greenhouse gas emissions (GHGS), break fossil fuel dependence, and secure a stable, low-carbon energy supply for enduring ecological balance. Thus, this study pioneers an investigation into the time–frequency association between greenhouse gas emissions and its key drivers, specifically nuclear energy and renewable energy consumption in the United States. Additionally, the study examines the role of social globalization and economic growth using data from 1970:Q1 to 2023:Q4. To the best of the authors’ knowledge, this is the first empirical study to explore this connection through wavelet methods. The findings reveal that, across various time frequencies, GHGS and social globalization are negatively correlated, GHGS and renewable energy are negatively correlated, and GHGS and nuclear energy are negatively correlated. Based on these results, the study formulates a coordinated policy approach.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111660"},"PeriodicalIF":1.9,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144523361","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":"A neutron transport calculation approach via the coupling of 2D/1D and 3D SN nodal methods","authors":"Hongchun Wu ,&nbsp;Shuaizheng Li ,&nbsp;Jun Chen ,&nbsp;Guangwen Bi ,&nbsp;Zhouyu Liu ,&nbsp;Sifan Zhang ,&nbsp;Xinyu Zhou ,&nbsp;Liangzhi Cao","doi":"10.1016/j.anucene.2025.111663","DOIUrl":"10.1016/j.anucene.2025.111663","url":null,"abstract":"<div><div>The 2D/1D neutron transport method is a popular approach for high-fidelity neutron transport calculations. For some research or testing reactors, the reactor core is surrounded by heavy water, and outside the heavy water is light water. To obtain the spectrum in the heavy water and light water outside the core, the heavy water and light water domains must be included in the calculation. This significantly affects the calculation time and convergence when using the 2D/1D method. Therefore, a new neutron transport method based on the 2D/1D method and the 3D SN nodal method is proposed to address these issues. In this method, the reactor core is divided into two calculation domains. The reactor active core is calculated by the 2D/1D method with fine meshes, while the region outside the reactor core is calculated by the 3D SN nodal method. The two calculation domains are coupled by the boundary angular flux. The CMFD and parallel scheme are also implemented to accelerate the calculations. This method is applied to the C5G7 benchmark and JRR-3 reactor core. The numerical tests show that the efficiency and convergence of the coupling method are much better than those of the 2D/1D method while maintaining accuracy.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111663"},"PeriodicalIF":1.9,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366013","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":"Analysis and optimization of operating characteristics for integrated pressurized water reactor IP200","authors":"Ren Li ,&nbsp;Xu Yang ,&nbsp;Hao Xu ,&nbsp;Yuandong Zhang ,&nbsp;Genglei Xia ,&nbsp;Minjun Peng","doi":"10.1016/j.anucene.2025.111682","DOIUrl":"10.1016/j.anucene.2025.111682","url":null,"abstract":"<div><div>The integrated pressurized water reactor exhibits superior performance in terms of safety, economy, and modular implementation. However, the structural differences of the integrated pressurized water reactor make its operation more complex compared to traditional pressurized water reactors. This paper established a model for the integrated pressurized water reactor IP200 and analyzed the characteristics of typical operating conditions. Furthermore, the optimization of operational strategies for typical transient process was carried out based on intelligent algorithms. Specifically, the transient operational characteristics of the IP200 was analyzed by nuclear-thermal coupling method. During the step load change under forced circulation, the IP200 could achieve a rapid response within 40 s and reach a new stable state. However, the transition time during the transition from forced circulation to natural circulation was 461 s, exceeding the maneuverability indicators. Therefore, the paper used a multi-population genetic algorithm to optimize the operational strategies and obtained the optimal transition time. Under optimized operational strategy, the initial conversion power, average reactor temperature, and shut-off interval time of main coolant pump were 31.78 %FP, 572.48 K, and 0 s, respectively. The conversion time was reduced to 381 s, which was 17.4 % shorter than before, achieving thermal safety and maneuverability requirements.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111682"},"PeriodicalIF":1.9,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144472029","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":"Study on the irradiation mechanical behavior of three-petal fuel rods contact based on multi-physics field coupling","authors":"Weihua Cai ,&nbsp;Shusong Qin ,&nbsp;Binxian He ,&nbsp;Hao Yang ,&nbsp;Xiangfei Meng ,&nbsp;Wenchao Zhang ,&nbsp;Qian Li ,&nbsp;Jianchuang Sun","doi":"10.1016/j.anucene.2025.111673","DOIUrl":"10.1016/j.anucene.2025.111673","url":null,"abstract":"<div><div>The temperature and velocity fields in the fluid domain are crucial for the analysis of the mechanical properties of three-petal fuel rods (TPFR). Therefore, this study establishes a multi-physics field coupling model of coolant single-phase flow, heat transfer and fuel rods irradiation mechanics using ABAQUS-STAR CCM+. A gap of 0.03 mm is set between the fuel rods to accommodate fluid flow under unirradiated conditions. Subsequently, the thermal parameters are obtained to investigate the stress–strain and deformation distribution, when in contact with adjacent rods. The results indicate that the transverse velocity at different positions is related to the churning effect of the twisted petals. The counterclockwise side of the outer convex arc is affected by the higher-temperature coolant from the inner concave arc region, resulting in a higher heat transfer coefficient. Irradiation enhancement can reduce the risk of plastic deformation, when the burnup reaches 6.59 % fissions of initial metal atoms (FIMA), the maximum strain decreases from 0.0164 to 0.0015. Influenced by the heating power, the fuel rods exhibit non-uniform radial deformation along the axial direction, leading to varying contact states between adjacent rods. Axial elongation of the fuel rods can alleviate stress concentrations in these contact regions.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111673"},"PeriodicalIF":1.9,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366010","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":"Modeling and prediction of interfacial area transport in two-phase flow within a tight lattice bundle","authors":"Xu Yan ,&nbsp;Hengwei Zhang ,&nbsp;Yao Xiao ,&nbsp;Hanyang Gu","doi":"10.1016/j.anucene.2025.111666","DOIUrl":"10.1016/j.anucene.2025.111666","url":null,"abstract":"<div><div>The interfacial area concentration (IAC) is the two-fluid model’s key parameter, determining the interfacial transfer terms’ constitutive relations. To dynamically forecast IAC developments, the interfacial area transport equation (IATE) has been proposed. Tight lattice fuel assemblies with <em>P</em>/<em>D</em> &lt; 1.1 are extensively utilized in the conceptual designs of small modular reactors. To investigate the interface transport characteristics and develop the IATE for the tight lattice fuel assembly, we established a two-phase flow parameter database for a tight lattice rod bundle with <em>P</em>/<em>D</em> = 1.06, covering void fraction, bubble velocity, bubble size distribution (BSD), and IAC. The BSD and IAC data were obtained using an in-house developed wire-mesh sensor (WMS) combined with a new post-processing method, known as the Eulerian post-processing method. This paper utilized the IAC data in the tight lattice bundle channel to benchmark the classical IATE models, including the Fu, Sun, and Yang models. Results indicate the Fu model most accurately predictes the development of IAC in the current channel. For the one-group (G₁) flow, the Fu model’s average and maximum relative deviations are 5.1 % and 14.3 %, respectively. Meanwhile, for the two-group (G₂) flow, the Fu model’s average and maximum relative deviations are 12.1 % and 25.6 %, respectively. Based on the Fu model, combined with the G₂ bubbles’ characteristics in the tight lattice bundle, this paper proposes an optimized IATE model by correcting the G₂ bubble base shearing-off perimeter and shape factor. The optimized model suppresses the contribution of the shearing-off term and greatly improves the prediction accuracy of the two-group IAC evolution inside the current bundle channel. For the two-group flow, the new model’s average and maximum relative deviations of IAC are 6.56 % and 14.9 %, respectively. However, calculation results also show that the IATE may not predict the IAC and void fraction transport synchronously in some cases, due to the assumption of a flat bubble number density distribution. Hence, in future studies, the IATE considering BSD evolution information is recommended to be developed to further enhance the model accuracy.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111666"},"PeriodicalIF":1.9,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338883","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":"Study of the optimal layout of U-bolt restraints used for High-Energy pipelines based on parametric modeling","authors":"Ruoxi Yang,&nbsp;Xiao Han,&nbsp;Xia Yang,&nbsp;Xiaozhou Xia","doi":"10.1016/j.anucene.2025.111656","DOIUrl":"10.1016/j.anucene.2025.111656","url":null,"abstract":"<div><div>The protective design of high-temperature, high-pressure pipelines is critical for nuclear safety. Current specifications underestimate the injection forces compared to those in actual engineering scenarios. There has been limited research on anti-whipping components for high-energy pipelines, especially those operating above 300 °C and 30.0 MPa. This study utilized a collaborative simulation scheme combining ANSYS APDL (Ansys Parametric Design Language) and LS-DYNA to optimize U-bolt restraints for high-energy pipelines. Parametric modelling of U-bolt restraints was performed in ANSYS APDL, while impact simulations were conducted in LS-DYNA. Sensitivity analysis showed that the U-bolt restraint number, diameter, and fixed leg length significantly affected the anti-whipping performance. An anti-whipping failure criterion based on the kinetic energy was proposed and used in the optimization process. The results suggest that arranging three U-bolts obliquely in the pipeline’s elbow improves the performance, and for a double-bend pipe, intact U-bolts prevent failure from oblique loads.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111656"},"PeriodicalIF":1.9,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366012","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":"Carbon dioxide bubble dynamics and wall heat transfer in flash chambers: Nucleation departure and cold bubble effects","authors":"Qifan Wang ,&nbsp;Yansong Han ,&nbsp;Ailing Fu ,&nbsp;Shanfang Huang ,&nbsp;Ruohan Zheng ,&nbsp;Yanping Huang ,&nbsp;Houjun Gong","doi":"10.1016/j.anucene.2025.111674","DOIUrl":"10.1016/j.anucene.2025.111674","url":null,"abstract":"<div><div>This study uses the lattice Boltzmann method to explore bubble dynamics and phase-change heat transfer of carbon dioxide during reduced pressure flash evaporation near overheated wall surfaces. The findings show that the bubble advancing rate decreases linearly with increasing superheat and contact angle. Similarly, the detachment diameter decreases linearly as superheat increases. The relationship between detachment diameter and contact angle is strongly influenced by wall wettability: hydrophilic surfaces exhibit a negative linear correlation, while hydrophobic surfaces show a positive linear correlation. A correction term based on the Ca number is introduced to enhance bubble rising velocity predictions. Heat transfer analysis reveals that wall wettability significantly impacts heat flux, with hydrophobic surfaces boosting heat transfer by up to three times. Mechanistically, cold nuclei induced by low-pressure conditions are crucial for improved flash evaporation heat transfer, particularly on hydrophobic surfaces.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111674"},"PeriodicalIF":1.9,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144329906","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":"Melting of Fe and Gd oxide loaded geopolymers with nuclear fuel for ex-vessel core catcher systems","authors":"Bence Mészáros ,&nbsp;Jan Hrbek ,&nbsp;Mykhaylo Paukov ,&nbsp;Tomáš Černoušek ,&nbsp;Jan Sklenka ,&nbsp;Zbyněk Černý ,&nbsp;Pavlína Rosypal ,&nbsp;Václav Tyrpekl","doi":"10.1016/j.anucene.2025.111602","DOIUrl":"10.1016/j.anucene.2025.111602","url":null,"abstract":"<div><div>Geopolymers have demonstrated a significant potential in various fields of the nuclear industry. They can serve as enhanced sacrificial materials offering increased safety and mitigating consequences in a hypothetical severe nuclear accident. Additionally, geopolymers show potential use as immobilization matrixes for radioactive waste disposal due to their advantageous properties and polymeric structures. Their properties, including high gamma radiation resistance, low water content, and the ability to incorporate various elements and species to customize their physico-chemical properties, suggest that geopolymers may be applied for various systems, e.g. sacrificial materials for core catchers of current or future plant concepts. However, further research is required to fully understand the interaction between geopolymers and corium melts, to describe their physico-chemical properties at extreme temperatures, high-temperature phase behaviour, etc. In present manuscript, we focused on geopolymers with embedded Gd₂O₃ and Fe₂O₃ as neutron absorber and functional melt modifier, respectively. Such composite could be a convenient sacrificial material for ex-vessel core catcher systems. We conducted two midscale melting experiments of geopolymer mixtures with prototypic corium to estimate the solidus and liquidus of the mixture and asses the phase behaviour. The mixture of geopolymer and prototypic corium showed similarities to previously described corium-concrete systems with solidus temperature around 1500 °C and liquidus around 1900 °C. A miscibility gap was present in the system between the oxide and iron melt. Iron melt solidified into a large block, but to microdroplets as well. Three distinct phases (silicate-rich, uranium-rich and metallic) were observed in the ingots. The geopolymer materials appeared to have prospective properties from melting and phase point of view, thus deserve further attention in the severe accident R&amp;D.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111602"},"PeriodicalIF":1.9,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144523362","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":"On-The-Fly multigroup cross section generation method with continuous energy accuracy","authors":"Farzad Rahnema,&nbsp;Dingkang Zhang","doi":"10.1016/j.anucene.2025.111640","DOIUrl":"10.1016/j.anucene.2025.111640","url":null,"abstract":"<div><div>In this paper, an on-the-fly multigroup cross section generation method is developed and implemented into the coarse mesh transport code COMET to account for the effects of spectral change and surrounding environment in reactor core calculations. The method consists of (1) a continuous energy stochastic response reaction rate generation module and (2) a deterministic multigroup cross section updating module. The first module is developed by extending the continuous energy response function generator for COMET to solve a set of local fixed-source transport problems with incident flux boundary conditions (or surface sources) and to generate a library of various response reaction rates. The second module constructs the phase space (continuous in space, angle, and energy) flux distribution in the regions of interest as a superposition of elements from the pre-computed library and then generates the multigroup cross sections on-the-fly. The method is benchmarked against the multigroup cross sections directly by continuous energy Monte Carlo in a set of stylized Very High Temperature Reactor (VHTR) single fuel block and whole core benchmark problems. Benchmark results demonstrate that the new method can achieve accuracy close (i.e., within two standard deviation of stochastic uncertainty) to that of continuous energy Monte Carlo while having on-the-fly computational speed.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"223 ","pages":"Article 111640"},"PeriodicalIF":1.9,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144329905","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}