Frontiers in Nuclear Engineering最新文献_第2页

Assessment of the three-dimensional flow field in the reactor pressure vessel in Hualong One nuclear power plants 评估 "华龙一号 "核电站反应堆压力容器内的三维流场

Frontiers in Nuclear Engineering Pub Date : 2024-02-16 DOI: 10.3389/fnuen.2024.1359616

Zonglan Wei, Songwei Li, Sijia Du, Yazhe Lu, Zhifang Qiu

{"title":"Assessment of the three-dimensional flow field in the reactor pressure vessel in Hualong One nuclear power plants","authors":"Zonglan Wei, Songwei Li, Sijia Du, Yazhe Lu, Zhifang Qiu","doi":"10.3389/fnuen.2024.1359616","DOIUrl":"https://doi.org/10.3389/fnuen.2024.1359616","url":null,"abstract":"This study uses computational fluid dynamics (CFD) to investigate the three-dimensional flow field under normal operating conditions in the reactor pressure vessel (RPV) in the Hualong One nuclear power plants (NPPs). With a particular focus on the flowrate distribution at the core inlet, the numerical framework is validated against the integral hydraulic experiment in a 1:4-scaled RPV of CNP1000, the prototype of the Hualong One reactor. The simulation results of the normalized flowrate at the core inlet agree reasonably well with the measured data. Based on the experimental data, several methods of calibrating the CFD turbulence model coefficients are suggested by introducing the concepts of data assimilation and machine learning. The flow field in a realistic RPV for Hualong One is predicted using the validated numerical framework, showing that the flowrate distribution at the core inlet is nearly homogeneous and that the turbulent intensity is acceptably low for each fuel assembly. It can provide essential information for the reactor core thermal–hydraulic design and the fuel assembly mechanical assessment.","PeriodicalId":505786,"journal":{"name":"Frontiers in Nuclear Engineering","volume":"32 21","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139962098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spectroscopic analysis of Pu-bearing compounds in double-walled cells 双壁电池中含钚化合物的光谱分析

Frontiers in Nuclear Engineering Pub Date : 2024-02-16 DOI: 10.3389/fnuen.2024.1355374

E. Villa‐Aleman, Jason R. Darvin, Don D. Dick, Michael C. Maxwell, A. Swindle, Bryan J. Foley

{"title":"Spectroscopic analysis of Pu-bearing compounds in double-walled cells","authors":"E. Villa‐Aleman, Jason R. Darvin, Don D. Dick, Michael C. Maxwell, A. Swindle, Bryan J. Foley","doi":"10.3389/fnuen.2024.1355374","DOIUrl":"https://doi.org/10.3389/fnuen.2024.1355374","url":null,"abstract":"Spectroscopic analysis of radiological materials has been historically limited to radiological labs with older or less advanced scientific instrumentation. The development of double-walled cells (DWCs) at the Savannah River National Laboratory (SRNL) has enabled Pu-bearing compounds to be removed from radiological laboratories and studied in our radiologically clean spectroscopy laboratory with state-of-the-art instrumentation. In this manuscript, we discuss the contributions of DWCs that have allowed the application of Raman spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), diffuse reflectance spectroscopy (DRS) in the shortwave infrared, and gamma spectroscopy at SRNL. Significant advances have been made in the understanding of the thermal decomposition of Pu(III) and Pu(IV) oxalates, alpha-induced damage to the PuO2 crystal lattice, and the effect of calcination temperatures on the quality of PuO2. These techniques have enabled methods to conduct PuO2 age dating since last calcination and estimate the calcination temperature with Raman spectroscopy and DRS. Additional spectroscopic information measured with DRIFTS has enabled the observation of the evolution of carbon species with calcination temperature, while gamma spectroscopy provides information on age dating since last purification.","PeriodicalId":505786,"journal":{"name":"Frontiers in Nuclear Engineering","volume":"57 48","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139960805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fabrication of neutron absorbing metal hydride entrained ceramic matrix shield composites 制造中子吸收金属氢化物夹杂陶瓷基屏蔽复合材料

Frontiers in Nuclear Engineering Pub Date : 2024-02-16 DOI: 10.3389/fnuen.2024.1352667

Devanshi Bhardwaj, Bin Cheng, David J. Sprouster, William S. Cunningham, Nirmala Rani, J. Trelewicz, L. Snead

{"title":"Fabrication of neutron absorbing metal hydride entrained ceramic matrix shield composites","authors":"Devanshi Bhardwaj, Bin Cheng, David J. Sprouster, William S. Cunningham, Nirmala Rani, J. Trelewicz, L. Snead","doi":"10.3389/fnuen.2024.1352667","DOIUrl":"https://doi.org/10.3389/fnuen.2024.1352667","url":null,"abstract":"With significant improvement in High Temperature Superconductors (HTS), several projects are adopting HTS technology for fusion power systems. Compact HTS tokamaks offer potential advantages including lower plant costs, enhanced plasma control, and ultimately lower cost of electricity. However, as compact reactors have a reduced radial build to accommodate shielding, HTS degradation due to radiation damage or heating is a significant and potentially design limiting issue. Shielding must mitigate threats to the superconducting coils: neutron cascade damage, heat deposition and potentially organic insulator damage due x-rays. Unfortunately, there are currently no hi-performance shielding materials to enable the potential performance enhancement offered by HTS. In this work, we present a manufacturing method to fabricate a new class of composite shields that are high performance, high operating temperature, and simultaneously neutron absorbing and neutron moderating. The composite design consists of an entrained metal-hydride phase within a radiation stable MgO ceramic host matrix. We discuss the fabrication, characterization, and thermophysical performance data for a series of down-selected composite materials inspired by future fusion core designs and their operational performance metrics. To our knowledge these materials represent the first ceramic composite shield materials containing significant metal hydrides.","PeriodicalId":505786,"journal":{"name":"Frontiers in Nuclear Engineering","volume":"33 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139962481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The effects of flux on the radiation-induced embrittlement of reactor pressure vessel steels: review of current understanding and application to high fluences 通量对反应堆压力容器钢辐射诱发脆化的影响：回顾目前的理解和对高通量的应用

Frontiers in Nuclear Engineering Pub Date : 2024-02-07 DOI: 10.3389/fnuen.2024.1339222

Susan Ortner, P. Styman, Elliot Long

{"title":"The effects of flux on the radiation-induced embrittlement of reactor pressure vessel steels: review of current understanding and application to high fluences","authors":"Susan Ortner, P. Styman, Elliot Long","doi":"10.3389/fnuen.2024.1339222","DOIUrl":"https://doi.org/10.3389/fnuen.2024.1339222","url":null,"abstract":"It is necessary to quantify the effects of flux on reactor pressure vessel steel embrittlement under neutron irradiation, if surveillance or high-flux test reactor data is used to predict vessel embrittlement occurring at lower fluxes. This is particularly important when considering embrittlement occurring during extended (60–80 years) operation for which there is no direct experience. Dedicated investigations are time-consuming and expensive even when only small flux-fluence ranges are investigated, so collating data from multiple campaigns is necessary to provide sufficient information to cover the wide range of fluxes required for vessel assessment in the long term. This paper collates and reviews such data. The review finds that flux dependences probably differ in sign and strength in different regimes (low flux and fluence, intermediate flux at low and high fluence, high flux at low and high fluence) with the regime limits affected by composition and temperature. The current understanding of diffusion processes and microstructural development are invaluable in interpreting the trends and limits. Many contradictory data sets were found, however, and not all contradictions could be dismissed as resulting from poor quality data. Suggestions are made for investigations to clarify the uncertainties. One wide-ranging model of flux effects, based on an extensive data set, is used to compare high-fluence data from different sources, to assess whether embrittlement rates accelerate after a high, threshold fluence. The model helps to identify experiments which investigated comparable flux-fluence-temperature regimes. The comparable data are split evenly between data sets supporting acceleration after a particular fluence and data sets contradicting it. The model identifies regimes in which further campaigns would clarify the causes of these contrasting observations.","PeriodicalId":505786,"journal":{"name":"Frontiers in Nuclear Engineering","volume":"11 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139795013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The effects of flux on the radiation-induced embrittlement of reactor pressure vessel steels: review of current understanding and application to high fluences 通量对反应堆压力容器钢辐射诱发脆化的影响：回顾目前的理解和对高通量的应用

Frontiers in Nuclear Engineering Pub Date : 2024-02-07 DOI: 10.3389/fnuen.2024.1339222

Susan Ortner, P. Styman, Elliot Long

{"title":"The effects of flux on the radiation-induced embrittlement of reactor pressure vessel steels: review of current understanding and application to high fluences","authors":"Susan Ortner, P. Styman, Elliot Long","doi":"10.3389/fnuen.2024.1339222","DOIUrl":"https://doi.org/10.3389/fnuen.2024.1339222","url":null,"abstract":"It is necessary to quantify the effects of flux on reactor pressure vessel steel embrittlement under neutron irradiation, if surveillance or high-flux test reactor data is used to predict vessel embrittlement occurring at lower fluxes. This is particularly important when considering embrittlement occurring during extended (60–80 years) operation for which there is no direct experience. Dedicated investigations are time-consuming and expensive even when only small flux-fluence ranges are investigated, so collating data from multiple campaigns is necessary to provide sufficient information to cover the wide range of fluxes required for vessel assessment in the long term. This paper collates and reviews such data. The review finds that flux dependences probably differ in sign and strength in different regimes (low flux and fluence, intermediate flux at low and high fluence, high flux at low and high fluence) with the regime limits affected by composition and temperature. The current understanding of diffusion processes and microstructural development are invaluable in interpreting the trends and limits. Many contradictory data sets were found, however, and not all contradictions could be dismissed as resulting from poor quality data. Suggestions are made for investigations to clarify the uncertainties. One wide-ranging model of flux effects, based on an extensive data set, is used to compare high-fluence data from different sources, to assess whether embrittlement rates accelerate after a high, threshold fluence. The model helps to identify experiments which investigated comparable flux-fluence-temperature regimes. The comparable data are split evenly between data sets supporting acceleration after a particular fluence and data sets contradicting it. The model identifies regimes in which further campaigns would clarify the causes of these contrasting observations.","PeriodicalId":505786,"journal":{"name":"Frontiers in Nuclear Engineering","volume":"59 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139854683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A long-term dependable and reliable method for reactor accident prognosis using temporal fusion transformer 利用时态融合变压器进行反应堆事故预报的长期可靠方法

Frontiers in Nuclear Engineering Pub Date : 2024-02-07 DOI: 10.3389/fnuen.2024.1339457

Chengyuan Li, Mei-Jiu Li, Zhifang Qiu

{"title":"A long-term dependable and reliable method for reactor accident prognosis using temporal fusion transformer","authors":"Chengyuan Li, Mei-Jiu Li, Zhifang Qiu","doi":"10.3389/fnuen.2024.1339457","DOIUrl":"https://doi.org/10.3389/fnuen.2024.1339457","url":null,"abstract":"Introduction: The accurate prognosis of reactor accidents is essential for deploying effective strategies that prevent radioactive releases. However, research in the nuclear sector is limited. This paper introduces a novel Temporal Fusion Transformer (TFT) model-based method for accident prognosis that incorporates multi-headed self-attention and gating mechanisms.Methods: Our proposed method combines multi-headed self-attention and gating mechanisms of TFT with multiple covariates to enhance prediction accuracy. Additionally, we employ quantile regression for uncertainty assessment. We apply this method to the HPR1000 reactor to predict outcomes following loss of coolant accidents (LOCAs).Results: The experimental results reveal that our proposed method outperforms existing deep learning-based prediction models in both prediction accuracy and confidence intervals. We also demonstrate increased robustness through interference experiments with varying signal-to-noise ratios and ablation studies on static covariates.Discussion: Our method contributes to the development of intelligent and reduced-staff maintenance methods for reactor systems, showcasing its ability to effectively extract and utilize features of static and historical covariates for improved predictive performance.","PeriodicalId":505786,"journal":{"name":"Frontiers in Nuclear Engineering","volume":"43 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139855184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A long-term dependable and reliable method for reactor accident prognosis using temporal fusion transformer 利用时态融合变压器进行反应堆事故预报的长期可靠方法

Frontiers in Nuclear Engineering Pub Date : 2024-02-07 DOI: 10.3389/fnuen.2024.1339457

Chengyuan Li, Mei-Jiu Li, Zhifang Qiu

{"title":"A long-term dependable and reliable method for reactor accident prognosis using temporal fusion transformer","authors":"Chengyuan Li, Mei-Jiu Li, Zhifang Qiu","doi":"10.3389/fnuen.2024.1339457","DOIUrl":"https://doi.org/10.3389/fnuen.2024.1339457","url":null,"abstract":"Introduction: The accurate prognosis of reactor accidents is essential for deploying effective strategies that prevent radioactive releases. However, research in the nuclear sector is limited. This paper introduces a novel Temporal Fusion Transformer (TFT) model-based method for accident prognosis that incorporates multi-headed self-attention and gating mechanisms.Methods: Our proposed method combines multi-headed self-attention and gating mechanisms of TFT with multiple covariates to enhance prediction accuracy. Additionally, we employ quantile regression for uncertainty assessment. We apply this method to the HPR1000 reactor to predict outcomes following loss of coolant accidents (LOCAs).Results: The experimental results reveal that our proposed method outperforms existing deep learning-based prediction models in both prediction accuracy and confidence intervals. We also demonstrate increased robustness through interference experiments with varying signal-to-noise ratios and ablation studies on static covariates.Discussion: Our method contributes to the development of intelligent and reduced-staff maintenance methods for reactor systems, showcasing its ability to effectively extract and utilize features of static and historical covariates for improved predictive performance.","PeriodicalId":505786,"journal":{"name":"Frontiers in Nuclear Engineering","volume":"25 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139795188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Real-time infrared spectroscopy coupled with blind source separation for nuclear waste process monitoring 实时红外光谱与盲源分离相结合，用于核废料过程监测

Frontiers in Nuclear Engineering Pub Date : 2023-11-30 DOI: 10.3389/fnuen.2023.1295995

Steven H. Crouse, Stefani Kocevska, Sean Noble, Rupanjali Prasad, Anthony M. Howe, Dan P. Lambert, Ronald W. Rousseau, Martha A. Grover

{"title":"Real-time infrared spectroscopy coupled with blind source separation for nuclear waste process monitoring","authors":"Steven H. Crouse, Stefani Kocevska, Sean Noble, Rupanjali Prasad, Anthony M. Howe, Dan P. Lambert, Ronald W. Rousseau, Martha A. Grover","doi":"10.3389/fnuen.2023.1295995","DOIUrl":"https://doi.org/10.3389/fnuen.2023.1295995","url":null,"abstract":"On-line infrared absorbance spectroscopy enables rapid measurement of solution-phase molecular species. Many spectra-to-concentration models exist for spectral data, with some models able to handle overlapping spectral bands and nonlinearities. However, model accuracy is limited by the quality of training data used in model fitting. The process spectra of nuclear waste simulants at the Savannah River Site display incongruity between training and process spectra; the glycolate spectral signature in the training data does not match the glycolate signature in Savannah River National Laboratory process data. A novel blind source separation algorithm is proposed that preprocesses spectral data so that process spectra more closely resemble training spectra, thereby improving model quantification accuracy when unexpected sources of variation appear in process spectra. The novel blind source separation preprocessing algorithm is shown to improve nitrate quantification from an R2 of 0.934 to 0.988 and from 0.267 to 0.978 in two instances analyzing nuclear waste simulants from the Slurry Receipt Adjustment Tank and Slurry Mix Evaporator cycle at the Savannah River Site.","PeriodicalId":505786,"journal":{"name":"Frontiers in Nuclear Engineering","volume":"57 11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139198352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Review of SCWR research in Japan 日本超临界水资源研究回顾

Frontiers in Nuclear Engineering Pub Date : 2023-11-29 DOI: 10.3389/fnuen.2023.1272766

Yoshiaki Oka

引用次数: 0

Solids, colloids, and the hydrolysis of tetravalent uranium in chloride media 固体、胶体和四价铀在氯化物介质中的水解作用

Frontiers in Nuclear Engineering Pub Date : 2023-11-27 DOI: 10.3389/fnuen.2023.1308064

B. Grambow, R. Müller, D. Schild, X. Gaona

引用次数: 0