Journal of Nuclear Engineering and Radiation Science最新文献

Estimation of Turbulent Mixing Factor and Study of Turbulent Flow Structures in PWR Sub Channel by DNS 利用 DNS 估算压水堆副水道中的湍流混合因子并研究湍流结构

IF 0.5

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-07-20 DOI: 10.1115/1.4066001

Raj Kumar Singh, Deb Mukhopadhyay, D. Khakhar, J. B. Joshi

{"title":"Estimation of Turbulent Mixing Factor and Study of Turbulent Flow Structures in PWR Sub Channel by DNS","authors":"Raj Kumar Singh, Deb Mukhopadhyay, D. Khakhar, J. B. Joshi","doi":"10.1115/1.4066001","DOIUrl":"https://doi.org/10.1115/1.4066001","url":null,"abstract":"\u0000 Sub-channel analysis codes are presently a requirement for design and safety analysis of nuclear reactors. Among the crucial inputs for these codes, the turbulent mixing factor holds particular significance. However, acquiring this factor through experimental means proves to be a challenging endeavor, primarily due to the necessity for precise pressure equilibrium between sub-channels. Consequently, this requirement leads to the undertaking of expensive and intricate experiments for each new reactor or in cases where there are modifications in fuel bundle design. The need for Direct Numerical Simulation (DNS) stems from the challenges and costs involved in experimental techniques, and the uncertainties due to empiricism in Computational Fluid Dynamics (CFD) models.\u0000 In this study, DNS has been conducted across six Reynolds numbers, ranging from 17640 to 1.176×105, in the geometry of a Pressurized Water Reactor (PWR) sub-channel. The resulting turbulent flow structures have been computed and their dynamics is examined.\u0000 Furthermore, this paper presents a methodology for directly calculating the turbulent mixing factor from the fluctuating velocity field obtained from DNS data. The turbulent mixing process has been scrutinized in-depth, and a correlation for the turbulent mixing factor is developed. It is noted that most of the mixing occurs in the near-wall region. The study suggests different mixing factors for mass and momentum mixing. This paper aims to provide a comprehensive insight into the turbulent mixing phenomenon.","PeriodicalId":16756,"journal":{"name":"Journal of Nuclear Engineering and Radiation Science","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141820575","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

Effect of Radial Neutron Reflector on the Characteristics of Nuclear Fuel Burn-up Wave in a Fast Neutron Energy Spectrum Multiplying Medium: A Consistent Parametric Approach 径向中子反射器对快速中子能谱倍增介质中核燃料燃耗波特性的影响：一致参数法

IF 0.5

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-07-04 DOI: 10.1115/1.4065893

Dipanjan Ray, S. Saraswat, V. S. Bhadouria

{"title":"Effect of Radial Neutron Reflector on the Characteristics of Nuclear Fuel Burn-up Wave in a Fast Neutron Energy Spectrum Multiplying Medium: A Consistent Parametric Approach","authors":"Dipanjan Ray, S. Saraswat, V. S. Bhadouria","doi":"10.1115/1.4065893","DOIUrl":"https://doi.org/10.1115/1.4065893","url":null,"abstract":"\u0000 The influence of radial neutron reflector on the build-up and propagation of a nuclear fuel burn-up wave in a fast multiplying medium is investigated using a consistent parametric approach. Coupled multi-group neutron diffusion equations with burn-up evolution model are simulated on the two-dimensional cylindrical reactor geometry with azimuthal symmetry. Uranium-Plutonium transmutation model is considered, and the simulation is performed by using finite element multiphysics software package COMSOL. Transient characteristics of the burn-up wave are represented by two new parameters, namely, Transient Time (TT) and Transient Length (TL). TT and TL are defined as the time and distance required for the burn-up wave to attain its steady-state nature. Steady-state phases are characterized in terms of wave velocity, Full Width Half Maximum (FWHM), and 10% of Maximum (FW10M). A sensitivity study of steady-state and transient parameters is conducted for the different values of radial reflector thickness. The potential relevance of these characterization parameters on the development of optimal geometrical configuration of radial neutron reflector in B&amp;B based reactor design is addressed based on the sensitivity study.","PeriodicalId":16756,"journal":{"name":"Journal of Nuclear Engineering and Radiation Science","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141678122","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

Performance of B-CTMFD Detector Vs Ludlum 42-49B, Fuji NSN3 Detectors for Fission Energy Spectrum Neutron Detection with the Source within Lead/concrete Shielded Configurations B-CTMFD 探测器与 Ludlum 42-49B、Fuji NSN3 探测器在铅/混凝土屏蔽配置中的裂变能谱中子源探测方面的性能比较

IF 0.5

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-07-01 DOI: 10.1115/1.4065853

Yusuke Ota, R. Taleyarkhan

{"title":"Performance of B-CTMFD Detector Vs Ludlum 42-49B, Fuji NSN3 Detectors for Fission Energy Spectrum Neutron Detection with the Source within Lead/concrete Shielded Configurations","authors":"Yusuke Ota, R. Taleyarkhan","doi":"10.1115/1.4065853","DOIUrl":"https://doi.org/10.1115/1.4065853","url":null,"abstract":"\u0000 This paper presents the results of neutron detection efficiency and dosimetry between a borated centrifugally tensioned metastable fluid detector (B-CTMFD) vs He-3 Ludlum-42-49B, and, the Fuji NSN3 conducted using a Cf-252 neutron source behind lead and concrete shielding. MCNP code simulations accounted for 3-D effects and derived cpm/mic.Sv/h factors. Ludlum and NSN3 offer fixed sensitivity, but CTMFD offered on-demand sensitivity by varying its Pneg state between 0.3-0.7 MPa. The B-CTMFD demonstrated sensitivity of up to ~22x greater than Ludlum and 5x greater than NSN3, for 0-15 cm Pb shielding, and 0-30 cm concrete shielding; it overcomes the 60% detection penalty inherent in the NB-CTMF-designed only to detect fast-energy neutrons - as described in the companion (Part-1) paper. Unlike the NB-CTMFD, which used 100% DFP (C5H2F10), the B-CTMFD requires the use of an azeotropic mixture of DFP, methanol, and tri-methyl borate (TMB - using natural boron) in 80:4:16 proportion. The B-CTMFD was about 6 times more sensitive than NB-CTMFD under the most heavily shielded condition and taken together, also offered 2-energy bin neutron spectroscopic enablement, together with 22-5x higher absolute efficiency- relative sensitivity compared with the non-spectroscopic Ludlum (He-3) and NSN3 (methane-nitrogen) based detectors. From an intrinsic efficiency standpoint, the B-CTMFD operating at Pneg = 0.7 MPa state, demonstrated even superior ~103x higher intrinsic efficiency over Ludlum and NSN3.","PeriodicalId":16756,"journal":{"name":"Journal of Nuclear Engineering and Radiation Science","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141710877","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

Reviewing Welding Procedures - Checklists for Nuclear Power Systems 审核焊接程序 - 核动力系统核对表

IF 0.5

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-07-01 DOI: 10.1115/1.4065851

Zengkui Zhang, Chongzhi Wu, Zhenguo Peng, Mingkai Li

引用次数: 0

Performance of NB-CTMFD detector vs Ludlum 42-49B, and Fuji NSN3 detectors for hard (Am-Be) and soft (Cf-252 fission) energy spectra neutron sources within lead/concrete shielded configurations NB-CTMFD 探测器与 Ludlum 42-49B 和 Fuji NSN3 探测器在铅/混凝土屏蔽配置内用于硬（Am-Be）和软（Cf-252 裂变）能谱中子源时的性能比较

IF 0.5

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-07-01 DOI: 10.1115/1.4065852

Yusuke Ota, S. Ozerov, R. Taleyarkhan

{"title":"Performance of NB-CTMFD detector vs Ludlum 42-49B, and Fuji NSN3 detectors for hard (Am-Be) and soft (Cf-252 fission) energy spectra neutron sources within lead/concrete shielded configurations","authors":"Yusuke Ota, S. Ozerov, R. Taleyarkhan","doi":"10.1115/1.4065852","DOIUrl":"https://doi.org/10.1115/1.4065852","url":null,"abstract":"This paper presents results of neutron detection efficiency and dosimetry between a non-borated centrifugally tensioned metastable fluid detector (NB-CTMFD) configured to detect fast (>0.1 MeV) vs. He-3 based Ludlum-42-49B and the Fuji NSN3, detectors behind various levels of lead and concrete shieldin-together with MCNP code simulations to account for 3-D effects and to relate the detection sensitivity with the dose rate. The MCNP results for neutron energy spectra were validated vs. experimental measurements using the H*TMFD. While Ludlum and NSN3 operate at a fixed sensitivity, the NB-CTMFD detector offers variable sensitivity by varying the tensioned metastable negative pressure (Pneg) from 0.3 MPa to 0.7 MPa. The NB-CTMFD (configured for fast: > 0.2 MeV neutron detection) offered relative sensitivity enhancements of up to 15x greater than the Ludlum and ~5x greater than the NSN3 detector for low shielding thicknesses. For larger thicknesses, the advantage factor for NB-CTMFD unit reduces with increased fast neutron removal via down-scattering, which benefits the Ludlum and NSN3 detectors. Our companion paper compares performance with a Cf-252 spectrum using a borated CTMFD (covering dual energy bins: thermal-epithermal and fast energy ranges) wherein, it is demonstrated that the advantage factor for the CTMFD (if borated) remains elevated at the 5-10x higher level for low and large shielding thicknesses and soft and hard neutron spectra.","PeriodicalId":16756,"journal":{"name":"Journal of Nuclear Engineering and Radiation Science","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141704991","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

Practical Approach to Nuclear Shelter Wall Thickness Estimation 核防护墙厚度估算的实用方法

IF 0.4

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-05-06 DOI: 10.1115/1.4065463

Rayna Hristova, Stefan Simovsky

{"title":"Practical Approach to Nuclear Shelter Wall Thickness Estimation","authors":"Rayna Hristova, Stefan Simovsky","doi":"10.1115/1.4065463","DOIUrl":"https://doi.org/10.1115/1.4065463","url":null,"abstract":"\u0000 The authors goal was to provide a practical guideline on nuclear shelter wall thickness estimation. The shelter wall thickness is assessed on the basis of published data on radiation dose calculations, corroborated by field data from nuclear tests, and information or calculations of the dose attenuation in the shelter wall. Dose criterion is selected as the acceptable dose behind the shield. Doses from nuclear tests or simulations are summarized in tables in relation to bomb yield and distance from the explosion point. Neutron dose transmission factors, defined as ratio of the dose behind the shielding to the dose without shielding, and their interdependence with shield thickness for different materials were found in the references. Based on the required dose transmission factor, calculated with the selected dose criterion, the corresponding shelter concrete wall thickness is assessed, taken into account the relation with the dose transmission factors from the literature. For gamma rays the shield thickness is calculated on the basis of analytical functions describing the dependence between dose without shield, dose criterion and shield thickness. Data tables are provided with the assessed concrete wall thickness in relation to bomb yield and distance.","PeriodicalId":16756,"journal":{"name":"Journal of Nuclear Engineering and Radiation Science","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141007322","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

Modeling of N and P-type of Coaxial Ge Detectors Using MCNPX and the Effect of Dead Layer Variation on Its Response Function 使用 MCNPX 对 N 型和 P 型同轴 Ge 探测器进行建模以及死层变化对其响应函数的影响

IF 0.4

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-04-24 DOI: 10.1115/1.4065395

R.A. El-Tayebany, Mohamed Ali, Nawal Mohames, Rania Mohamed

引用次数: 0

Monitoring for Actinide Neutron Emissions From Spent Nuclear Fuel Under Extreme Gamma Fields Using Centrifugally Tensioned Metastable Fluid Detector Sensor Technology 利用离心张力可变流体探测器传感器技术监测乏核燃料在极端伽马场下的锕系中子发射情况

IF 0.4

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-04-06 DOI: 10.1115/1.4065280

C. Harabagiu, R. Taleyarkhan

{"title":"Monitoring for Actinide Neutron Emissions From Spent Nuclear Fuel Under Extreme Gamma Fields Using Centrifugally Tensioned Metastable Fluid Detector Sensor Technology","authors":"C. Harabagiu, R. Taleyarkhan","doi":"10.1115/1.4065280","DOIUrl":"https://doi.org/10.1115/1.4065280","url":null,"abstract":"\u0000 This paper presents research work focused on assessments for meeting the challenge of monitoring actinide content in spent nuclear fuel (SNF) via characteristic neutron emissions [from spontaneous fission and (α,n) reactions] with CTMFDs. A challenge problem was posed to examine if a CTMFD could operate reliably over 1 hour for conducting neutron spectroscopy at a 1 m standoff from a 30-y cooled SNF, in a ~1012:1 (gamma:neutron) and a 150 Gy (15 kRad) accumulated dose. The impacts on operability were studied for the effects of gamma radiation on: (i) radiolysis in the CTMFD sensing fluid; (ii) 3 MeV gamma photoneutrons; and, (iii) CTMFD electronics. A Co-60 irradiator was used for dose effects on the CTMFD. A 14 MeV DT accelerator was used with a NaCl target to produce 3-4 MeV photons from activated 37S (via. neutron absorption in 37Cl) expected from SNF at 1-m standoff. Our examinations revealed the absence of any significant impact on CTMFD performance for meeting and exceeding the challenge problem metrics. We validated for no discernible impact of: 3-4 MeV gamma-produced photoneutrons when combined with a fission neutron source and radiolysis in the DFP sensing fluid through a 150 Gy absorbed dose. Past research results at Purdue University have validated survivability above the targeted 150 Gy level. This paper also provides extended evidence for survivability (from radiolysis) at higher gamma doses through 750 Gy with a borated DFP-sensing fluid formulation-based CTMFD.","PeriodicalId":16756,"journal":{"name":"Journal of Nuclear Engineering and Radiation Science","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140734597","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

Validation Assessment of Turbulent Reacting Flow Model Using The Area-Validation Metric on Medium-Scale Methanol Pool Fire Results 利用中型甲醇池火灾结果的面积验证指标对湍流反应模型进行验证评估

IF 0.4

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-03-26 DOI: 10.1115/1.4065173

Jared Kirsch, Nima Fathi

{"title":"Validation Assessment of Turbulent Reacting Flow Model Using The Area-Validation Metric on Medium-Scale Methanol Pool Fire Results","authors":"Jared Kirsch, Nima Fathi","doi":"10.1115/1.4065173","DOIUrl":"https://doi.org/10.1115/1.4065173","url":null,"abstract":"\u0000 Accident analysis and ensuring power plant safety are pivotal in the nuclear energy sector. Significant strides have been achieved over the past few decades regarding fire protection and safety, primarily centered on design and regulatory compliance. Yet, after the Fukushima accident a decade ago, the imperative to enhance measures against fire, internal flooding, and power loss has intensified. Hence, a comprehensive, multilayered protection strategy against severe accidents is needed. Consequently, gaining a deeper insight into pool fires and their behavior through extensive validated data can greatly aid in improving these measures using advanced validation techniques. A model validation study was performed at Sandia National Laboratories in which a 30-cm diameter methanol pool fire was modeled using the SIERRA/Fuego turbulent reacting flow code. This validation study used a standard validation experiment to compare model results against, and conclusions have been published. The fire was modeled with a Large Eddy Simulation (LES) turbulence model with subgrid turbulent kinetic energy closure. Combustion was modeled using a strained laminar flamelet library approach. Radiative heat transfer was accounted for with a model utilizing the gray-gas approximation. In the present study, additional validation analysis is performed using the area validation metric (AVM). These activities are done on multiple datasets involving different variables and temporal/spatial ranges and intervals. The results provide insight into the use of the area validation metric on such temporally varying datasets and the importance of physics-aware use of the metric for proper analysis.","PeriodicalId":16756,"journal":{"name":"Journal of Nuclear Engineering and Radiation Science","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140379431","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

Development of Risk Informed Aging Management Program in Decommissioning 制定退役风险知情老化管理计划

IF 0.4

Journal of Nuclear Engineering and Radiation Science Pub Date : 2024-03-21 DOI: 10.1115/1.4065139

Masao Uesaka, Kenta Murakami

引用次数: 0