Pub Date : 2025-02-01DOI: 10.1016/j.net.2024.09.002
Mario Belotti, Rafael Juárez
As a result of the evolution of High-Performance Computing (HPC) and new cutting-edge projects such as ITER, nuclear analysis has greatly increased in sophistication. Nowadays, nuclear facilities can be modelled in unprecedented detail for radiation transport calculations. Radiation maps can reach great levels of complexity, including multiple radiation sources in vast geometries. These capabilities must be accompanied by an equal capacity to process the results obtained. Nowadays clients are provided with static views pre-decided by nuclear analysts to understand radiation fields. Since the ability to understand such information depends on the unevenly distributed spatial intelligence, this practice can induce biases and limit the usability of the calculations. But beyond analyst-client communication, analysts themselves often fail to identify cleanly all the aspects of a complex radiation field. To overcome to these limitations, we have expanded the videogame engine Unity to create IVR-UNED. It permits to build 3D videogame-like interactive virtual immersive environments, boosting the visualization and insight of the radiation fields through easy on-demand and real-time radiation field postprocessing and visualization. To demonstrate its features, the application to two relevant examples for fusion-related facilities, ITER and IFMIF-DONES, will be presented.
{"title":"IVR-UNED: Interactive virtual environments to understand radiation fields","authors":"Mario Belotti, Rafael Juárez","doi":"10.1016/j.net.2024.09.002","DOIUrl":"10.1016/j.net.2024.09.002","url":null,"abstract":"<div><div>As a result of the evolution of High-Performance Computing (HPC) and new cutting-edge projects such as ITER, nuclear analysis has greatly increased in sophistication. Nowadays, nuclear facilities can be modelled in unprecedented detail for radiation transport calculations. Radiation maps can reach great levels of complexity, including multiple radiation sources in vast geometries. These capabilities must be accompanied by an equal capacity to process the results obtained. Nowadays clients are provided with static views pre-decided by nuclear analysts to understand radiation fields. Since the ability to understand such information depends on the unevenly distributed spatial intelligence, this practice can induce biases and limit the usability of the calculations. But beyond analyst-client communication, analysts themselves often fail to identify cleanly all the aspects of a complex radiation field. To overcome to these limitations, we have expanded the videogame engine Unity to create IVR-UNED. It permits to build 3D videogame-like interactive virtual immersive environments, boosting the visualization and insight of the radiation fields through easy on-demand and real-time radiation field postprocessing and visualization. To demonstrate its features, the application to two relevant examples for fusion-related facilities, ITER and IFMIF-DONES, will be presented.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103199"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099955","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}
Pub Date : 2025-02-01DOI: 10.1016/j.net.2024.09.012
Peijun Li , Chen Hao , Ning Xu , Yanling Zhu , Yizhen Wang , Zhigang Zhang
The core physical behavior of reactors is essentially the result of multi-physical fields coupling feedback. High-fidelity neutronics/thermal-hydraulics (N/TH) analysis can simulate and predict nuclear reactor core phenomena realistically, providing advanced and reliable technical means during the design and safety analysis of nuclear reactor. In this work, an efficient and robustness coupling method using power density as the coupling parameter, Matrix-Free Newton Krylov (MFNK) method, is successfully developed and innovatively implemented in HNET for high-fidelity N/TH coupling simulation. To enhance the efficiency and stability, the multi-level generalized equivalence theory-based CMFD (ML-gCMFD) iterative acceleration method and ML-gCMFD coupling acceleration method are proposed. In addition, the nonlinear preconditioning and hybrid perturbation size formula are implemented to further improve the convergence. Finally, to evaluate the numerical accuracy, convergence, efficiency and stability of MFNK method, a series of representative problems, including a three-dimensional (3D) single fuel pin problem, VERA Benchmark Problem 6, and VERA Benchmark Problem 7, are analyzed by comparing with the current N/TH coupling methods. Numerical results indicate that MFNK method can obtain strong stability, high convergence performance, and relatively high computational efficiency while ensuring high accuracy. It demonstrates that MFNK method has significant performance advantages and potential for high-fidelity N/TH coupling simulation.
{"title":"An innovative and efficient implementation of matrix-free Newton krylov method for neutronics/thermal-hydraulics coupling simulation","authors":"Peijun Li , Chen Hao , Ning Xu , Yanling Zhu , Yizhen Wang , Zhigang Zhang","doi":"10.1016/j.net.2024.09.012","DOIUrl":"10.1016/j.net.2024.09.012","url":null,"abstract":"<div><div>The core physical behavior of reactors is essentially the result of multi-physical fields coupling feedback. High-fidelity neutronics/thermal-hydraulics (N/TH) analysis can simulate and predict nuclear reactor core phenomena realistically, providing advanced and reliable technical means during the design and safety analysis of nuclear reactor. In this work, an efficient and robustness coupling method using power density as the coupling parameter, Matrix-Free Newton Krylov (MFNK) method, is successfully developed and innovatively implemented in HNET for high-fidelity N/TH coupling simulation. To enhance the efficiency and stability, the multi-level generalized equivalence theory-based CMFD (ML-gCMFD) iterative acceleration method and ML-gCMFD coupling acceleration method are proposed. In addition, the nonlinear preconditioning and hybrid perturbation size formula are implemented to further improve the convergence. Finally, to evaluate the numerical accuracy, convergence, efficiency and stability of MFNK method, a series of representative problems, including a three-dimensional (3D) single fuel pin problem, VERA Benchmark Problem 6, and VERA Benchmark Problem 7, are analyzed by comparing with the current N/TH coupling methods. Numerical results indicate that MFNK method can obtain strong stability, high convergence performance, and relatively high computational efficiency while ensuring high accuracy. It demonstrates that MFNK method has significant performance advantages and potential for high-fidelity N/TH coupling simulation.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103209"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207206","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}
Pub Date : 2025-02-01DOI: 10.1016/j.net.2024.08.066
Xinxin Li , Yuan He , Wenjing Ma , Wenjuan Cui , Zhiyong He , Detai Zhou , Hai Zheng , Feng Yang , Yuhui Guo , Haihua Niu , Kai Yin , Shiwu Dang
This paper reports the control strategy for the core power in an accelerator drive sub-critical (ADS) system. In an ADS system, the intense external neutron source provided by a proton accelerator coupled to a spallation target is used to drive a sub-critical reactor. The proposed control strategy is to control the reactor power by adjusting the proton beam power, where the beam power is adjusted by changing either the duty factor or the intensity of the proton beam. As an example, the reactor power control of the China initiative Accelerator Driven System (CiADS) facility has been studied by adjusting the beam power. Firstly, the beam power is set roughly by assigning a new duty factor, where the duty factor is set by changing the beam macro-pulse length and the pulse repetition rate of the proton beam. Both the pulse length and the repetition rate are assigned by a timing system. Secondly, the power is adjusted precisely by changing the beam intensity. To change continuously the beam intensity, an adjustable aperture is used to block the outer particles of the beam line in the accelerator. In order to evaluate the proposed control strategy, a CiADS core model is built based on the multi-node point reactor dynamics model. Three cases, the start of the facility, the decrease of core power and the increase of core power, have been simulated with the model. The simulation results indicate that the control strategy for the core power by changing either the duty factor or the intensity of the proton beam works very well during the operation of the facility.
{"title":"Control strategy for the core power in an accelerator drive sub-critical system","authors":"Xinxin Li , Yuan He , Wenjing Ma , Wenjuan Cui , Zhiyong He , Detai Zhou , Hai Zheng , Feng Yang , Yuhui Guo , Haihua Niu , Kai Yin , Shiwu Dang","doi":"10.1016/j.net.2024.08.066","DOIUrl":"10.1016/j.net.2024.08.066","url":null,"abstract":"<div><div>This paper reports the control strategy for the core power in an accelerator drive sub-critical (ADS) system. In an ADS system, the intense external neutron source provided by a proton accelerator coupled to a spallation target is used to drive a sub-critical reactor. The proposed control strategy is to control the reactor power by adjusting the proton beam power, where the beam power is adjusted by changing either the duty factor or the intensity of the proton beam. As an example, the reactor power control of the China initiative Accelerator Driven System (CiADS) facility has been studied by adjusting the beam power. Firstly, the beam power is set roughly by assigning a new duty factor, where the duty factor is set by changing the beam macro-pulse length and the pulse repetition rate of the proton beam. Both the pulse length and the repetition rate are assigned by a timing system. Secondly, the power is adjusted precisely by changing the beam intensity. To change continuously the beam intensity, an adjustable aperture is used to block the outer particles of the beam line in the accelerator. In order to evaluate the proposed control strategy, a CiADS core model is built based on the multi-node point reactor dynamics model. Three cases, the start of the facility, the decrease of core power and the increase of core power, have been simulated with the model. The simulation results indicate that the control strategy for the core power by changing either the duty factor or the intensity of the proton beam works very well during the operation of the facility.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103197"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207215","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}
Pub Date : 2025-01-01DOI: 10.1016/j.net.2024.08.037
Z. Chen , Z.W. Pan , Z. Wang , Z.Y. He , Z.B. Lin , T.Y. Yang , Y. Wang , Z.Y. Zhang , J.D. Liu , S.B. Liu , B.J. Ye , L.W. Chen , Y.H. Yu
The characteristics of high energy cosmic-ray muons make them strongly penetrative in materials. It has great potential to monitor the stability of buildings by reconstructing the tracks of cosmic-ray muons. In this work, a buildings stability monitoring system based on plastic scintillator strips is proposed. The monitoring system consists of a single-plane upper telescope to record the incoming track of a muon, and a three-plane lower telescope to track its outgoing trajectory. Every detector plane is formed by orthogonally placed scintillator strips. The impacts of the scintillator geometry and spatial placement on the stability monitoring precision are carefully studied using Geant4 simulations. A sub-millimeter position resolution is achievable by selecting a proper data taking time. The triangular scintillator strips always outperform rectangular ones of the same size and placement. Two empirical formulas have been derived to quantitatively estimate the position resolution with respect to the abovementioned influential factors. In addition, the comprehensive effects of multiple parameters are also studied. Accordingly, triangular scintillator strips will be utilized in the construction of a real monitoring system with better performance and less detection channels. The simulation study in this work can provide good guidance for the manufacturing of triangular strips and their experimental configurations.
{"title":"Performance simulation study of plastic scintillator arrays for stability monitoring applications","authors":"Z. Chen , Z.W. Pan , Z. Wang , Z.Y. He , Z.B. Lin , T.Y. Yang , Y. Wang , Z.Y. Zhang , J.D. Liu , S.B. Liu , B.J. Ye , L.W. Chen , Y.H. Yu","doi":"10.1016/j.net.2024.08.037","DOIUrl":"10.1016/j.net.2024.08.037","url":null,"abstract":"<div><div>The characteristics of high energy cosmic-ray muons make them strongly penetrative in materials. It has great potential to monitor the stability of buildings by reconstructing the tracks of cosmic-ray muons. In this work, a buildings stability monitoring system based on plastic scintillator strips is proposed. The monitoring system consists of a single-plane upper telescope to record the incoming track of a muon, and a three-plane lower telescope to track its outgoing trajectory. Every detector plane is formed by orthogonally placed scintillator strips. The impacts of the scintillator geometry and spatial placement on the stability monitoring precision are carefully studied using Geant4 simulations. A sub-millimeter position resolution is achievable by selecting a proper data taking time. The triangular scintillator strips always outperform rectangular ones of the same size and placement. Two empirical formulas have been derived to quantitatively estimate the position resolution with respect to the abovementioned influential factors. In addition, the comprehensive effects of multiple parameters are also studied. Accordingly, triangular scintillator strips will be utilized in the construction of a real monitoring system with better performance and less detection channels. The simulation study in this work can provide good guidance for the manufacturing of triangular strips and their experimental configurations.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 1","pages":"Article 103168"},"PeriodicalIF":2.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143180147","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}
Pub Date : 2025-01-01DOI: 10.1016/j.net.2024.08.025
Danwoo Ko , Seunguk Cheon , Jiyoung Kim , Seungmin Lee , Seung Min Woo
There is an argument that the Comprehensive Safeguards Agreement (CSA) should be applied to the milling process, which is the first stage of nuclear fuel cycle, to reduce the possibility of nuclear proliferation. Therefore, this study aims to propose new and conceptual safeguards applicable to milling facilities and design Nuclear Material Accountancy for its application. Mill tailings reach a secular equilibrium state. While approaching this equilibrium state, the ratio of each isotope changes. First, the Bateman equation was used to analyze this phenomenon and evaluate the feasibility of utilizing the specific isotope ratio to track undeclared nuclear activities. Second, the gamma spectrum analysis of mill tailings was conducted using the Monte Carlo N-Particle Code to validate undeclared nuclear activities. This study shows that the ratio of U-235/Th-234 and U-235/Pa-234m can estimate the production time within a year. Furthermore, gamma spectrum analysis of mill tailings revealed visible differences in the low-energy region due to the decay of Th-234. Finally, a conceptual Material Balance Area, Key Measurement Points, and Material Balance Period for milling facilities were designed to apply CSA. It is anticipated that applying CSA to milling facilities could enhance not only the nuclear fuel cycles but also nuclear non-proliferation system.
{"title":"Conceptual safeguards method proposal for milling facilities based on nuclear isotopic ratios in uranium mill tailings","authors":"Danwoo Ko , Seunguk Cheon , Jiyoung Kim , Seungmin Lee , Seung Min Woo","doi":"10.1016/j.net.2024.08.025","DOIUrl":"10.1016/j.net.2024.08.025","url":null,"abstract":"<div><div>There is an argument that the Comprehensive Safeguards Agreement (CSA) should be applied to the milling process, which is the first stage of nuclear fuel cycle, to reduce the possibility of nuclear proliferation. Therefore, this study aims to propose new and conceptual safeguards applicable to milling facilities and design Nuclear Material Accountancy for its application. Mill tailings reach a secular equilibrium state. While approaching this equilibrium state, the ratio of each isotope changes. First, the Bateman equation was used to analyze this phenomenon and evaluate the feasibility of utilizing the specific isotope ratio to track undeclared nuclear activities. Second, the gamma spectrum analysis of mill tailings was conducted using the Monte Carlo N-Particle Code to validate undeclared nuclear activities. This study shows that the ratio of U-235/Th-234 and U-235/Pa-234m can estimate the production time within a year. Furthermore, gamma spectrum analysis of mill tailings revealed visible differences in the low-energy region due to the decay of Th-234. Finally, a conceptual Material Balance Area, Key Measurement Points, and Material Balance Period for milling facilities were designed to apply CSA. It is anticipated that applying CSA to milling facilities could enhance not only the nuclear fuel cycles but also nuclear non-proliferation system.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 1","pages":"Article 103156"},"PeriodicalIF":2.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207254","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}
Pub Date : 2025-01-01DOI: 10.1016/j.net.2024.08.004
Maryam Al Huwayz , Aljawhara H. Almuqrin , F.F. Alharbi , M.I. Sayyed , B. Albarzan
This research focuses on the preparation of a new glass system designed specifically for applications in radiation shielding materials. These glasses are based on the general formula (56-x)B2O3–10TiO2–8BaO–27ZnO-(x-1)Nd2O3, where x takes the values of 2, 4, 6 and 8 mol%. For the examination of the designed glasses' radiation attenuation performance, Phy-X software was used, which is a useful approach for predicting the linear attenuation coefficient (LAC), the half value layer (HVL), and effective atomic number. The LAC decreases from 1.489 cm−1 to 0.551 cm−1 for the glass with x = 1 mol%, while the glass with 7 mol% Nd2O3 saw a decrease in the LAC from 2.483 cm−1 to 0.718 cm−1. Introducing Nd2O3 increases the glasses' LAC, suggesting enhanced radiation shielding performance. Also, Nd2O3 addition influences the HVL within the glasses, with higher content reducing the HVL. At 0.122 MeV, the HVL and tenth value layer (TVL) are 0.456 and 1.546 cm, respectively. At 0.245 MeV, the TVL is about 3.32 times higher than the HVL. The lowest mean free path (MFP) is found at 0.122 MeV, which varies between 0.672 cm for Nd1 and 0.403 cm for Nd4.
{"title":"Unveiling the potential of Nd2O3 in optimizing the radiation shielding performance of B2O3–TiO2–BaO–ZnO-Nd2O3 glasses","authors":"Maryam Al Huwayz , Aljawhara H. Almuqrin , F.F. Alharbi , M.I. Sayyed , B. Albarzan","doi":"10.1016/j.net.2024.08.004","DOIUrl":"10.1016/j.net.2024.08.004","url":null,"abstract":"<div><div>This research focuses on the preparation of a new glass system designed specifically for applications in radiation shielding materials. These glasses are based on the general formula (56-x)B<sub>2</sub>O<sub>3</sub>–10TiO<sub>2</sub>–8BaO–27ZnO-(x-1)Nd<sub>2</sub>O<sub>3</sub>, where x takes the values of 2, 4, 6 and 8 mol%. For the examination of the designed glasses' radiation attenuation performance, Phy-X software was used, which is a useful approach for predicting the linear attenuation coefficient (LAC), the half value layer (HVL), and effective atomic number. The LAC decreases from 1.489 cm<sup>−1</sup> to 0.551 cm<sup>−1</sup> for the glass with x = 1 mol%, while the glass with 7 mol% Nd<sub>2</sub>O<sub>3</sub> saw a decrease in the LAC from 2.483 cm<sup>−1</sup> to 0.718 cm<sup>−1</sup>. Introducing Nd<sub>2</sub>O<sub>3</sub> increases the glasses' LAC, suggesting enhanced radiation shielding performance. Also, Nd<sub>2</sub>O<sub>3</sub> addition influences the HVL within the glasses, with higher content reducing the HVL. At 0.122 MeV, the HVL and tenth value layer (TVL) are 0.456 and 1.546 cm, respectively. At 0.245 MeV, the TVL is about 3.32 times higher than the HVL. The lowest mean free path (MFP) is found at 0.122 MeV, which varies between 0.672 cm for Nd1 and 0.403 cm for Nd4.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 1","pages":"Article 103135"},"PeriodicalIF":2.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207273","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}
Pub Date : 2025-01-01DOI: 10.1016/j.net.2024.11.035
Sungtaek Hong , Taesuk Oh , Yonghee Kim
{"title":"Corrigendum to “A study on the applicability of simplified few-group GET (Generalized Equivalence Theory) to cylindrical molten salt fast reactor” [Nucl. Eng. Technol. 56 (10) (2024) 4207–4218]","authors":"Sungtaek Hong , Taesuk Oh , Yonghee Kim","doi":"10.1016/j.net.2024.11.035","DOIUrl":"10.1016/j.net.2024.11.035","url":null,"abstract":"","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 1","pages":"Article 103333"},"PeriodicalIF":2.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143180958","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}
Pub Date : 2025-01-01DOI: 10.1016/j.net.2024.08.033
P. Martinez-Reviriego , N. Fuster-Martínez , D. Esperante , M. Boronat , B. Gimeno , C. Blanch , D. González-Iglesias , P. Martín-Luna , E. Martínez , A. Menendez , L. Pedraza , J. Fernández , J. Fuster , A. Grudiev , N. Catalan Lasheras , W. Wuensch
High-Gradient accelerating cavities are one of the main research lines in the development of compact linear accelerators. However, the operation of such accelerating cavities is currently limited by non-linear electromagnetic effects that are intensified at high electric fields, such as RF breakdowns, dark currents and radiation. A novel normal-conducting High Gradient S-band Backward Travelling Wave accelerating cavity for medical application (v = 0.38c) has been designed and constructed at CERN with a design gradient of 50 MV/m. In this paper, the high-power performance studies of this novel design carried out at the IFIC high-power laboratory are presented, as well as the analysis of the conditioning parameters in combination with numerical simulations.
高梯度加速腔是开发紧凑型直线加速器的主要研究方向之一。然而,这种加速腔的运行目前受到非线性电磁效应的限制,这些效应在高电场下会加剧,如射频击穿、暗电流和辐射。欧洲核子研究中心(CERN)设计并建造了一个用于医疗应用的新型常导高梯度 S 波段后向游波加速腔(v = 0.38c),其设计梯度为 50 MV/m。本文介绍了在 IFIC 高功率实验室对这种新型设计进行的高功率性能研究,以及结合数值模拟对调节参数进行的分析。
{"title":"High-power performance studies of an S-band high-gradient accelerating cavity for medical applications","authors":"P. Martinez-Reviriego , N. Fuster-Martínez , D. Esperante , M. Boronat , B. Gimeno , C. Blanch , D. González-Iglesias , P. Martín-Luna , E. Martínez , A. Menendez , L. Pedraza , J. Fernández , J. Fuster , A. Grudiev , N. Catalan Lasheras , W. Wuensch","doi":"10.1016/j.net.2024.08.033","DOIUrl":"10.1016/j.net.2024.08.033","url":null,"abstract":"<div><div>High-Gradient accelerating cavities are one of the main research lines in the development of compact linear accelerators. However, the operation of such accelerating cavities is currently limited by non-linear electromagnetic effects that are intensified at high electric fields, such as RF breakdowns, dark currents and radiation. A novel normal-conducting High Gradient S-band Backward Travelling Wave accelerating cavity for medical application (v = 0.38c) has been designed and constructed at CERN with a design gradient of 50 MV/m. In this paper, the high-power performance studies of this novel design carried out at the IFIC high-power laboratory are presented, as well as the analysis of the conditioning parameters in combination with numerical simulations.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 1","pages":"Article 103164"},"PeriodicalIF":2.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207246","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}
Pub Date : 2025-01-01DOI: 10.1016/j.net.2024.08.020
Hyeongjin Byeon, Ugyu Jeong, Jaeyeong Park
Homogeneity is an important factor for ensuring the structural stability of solidified radioactive waste, and the most effective approach for assessing its homogeneity is by performing compressive strength measurements using the minimum amount of coring specimens. The efficiency of detecting inhomogeneous waste is affected by the coring position and number of coring positions. However, no guidelines exist for coring solidified waste for compressive-strength tests. Therefore, this study compared uniform, random, and quasi-Monte Carlo sampling methods to determine the most effective core position. Further, the effects of different sampling amounts on the detection rate of inhomogeneous solidified waste were observed, and the detection rate of the inhomogeneous waste was obtained by modeling the coring procedure of solidified radioactive waste using MATLAB. Thus, a sampling method and a method for increasing the specimen amount, both of which can efficiently detect inhomogeneous waste during compressive strength tests, were presented in this paper. The results of this study can be applied as background data for developing homogeneity assessment guidelines for solidified radioactive waste.
{"title":"Statistical sampling method to verify the homogeneity of full-scale cement-solidified radioactive waste","authors":"Hyeongjin Byeon, Ugyu Jeong, Jaeyeong Park","doi":"10.1016/j.net.2024.08.020","DOIUrl":"10.1016/j.net.2024.08.020","url":null,"abstract":"<div><div>Homogeneity is an important factor for ensuring the structural stability of solidified radioactive waste, and the most effective approach for assessing its homogeneity is by performing compressive strength measurements using the minimum amount of coring specimens. The efficiency of detecting inhomogeneous waste is affected by the coring position and number of coring positions. However, no guidelines exist for coring solidified waste for compressive-strength tests. Therefore, this study compared uniform, random, and quasi-Monte Carlo sampling methods to determine the most effective core position. Further, the effects of different sampling amounts on the detection rate of inhomogeneous solidified waste were observed, and the detection rate of the inhomogeneous waste was obtained by modeling the coring procedure of solidified radioactive waste using MATLAB. Thus, a sampling method and a method for increasing the specimen amount, both of which can efficiently detect inhomogeneous waste during compressive strength tests, were presented in this paper. The results of this study can be applied as background data for developing homogeneity assessment guidelines for solidified radioactive waste.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 1","pages":"Article 103151"},"PeriodicalIF":2.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207255","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}
Pub Date : 2025-01-01DOI: 10.1016/j.net.2024.08.005
Andrew K. Gillespie, Cuikun Lin, Django Jones, Sandeep Puri, R.V. Duncan
Materials used to study nuclear fusion can retain atmospheric helium unless pretreated before an experiment. Understanding helium outgassing is important for accurate diagnostics in experiments surrounding nuclear fusion. The presence of helium is often cited as the primary evidence that a nuclear reaction has occurred, so it is imperative that known sources of helium are mitigated prior to proceeding with novel nuclear experiments. It is also necessary to ensure hermeticity when transferring gas aliquots from an experiment to a mass spectrometer. In this article, we present studies of helium leak rates in systems used in novel nuclear experiments. We also present studies of helium retention in materials subjected to various heating profiles and atmospheric concentrations. Without pretreatment, 12-inch lengths of both 3/8” diameter tubes and 1/2″ diameter stainless-steel 316 tubing yielded an average areal outgassing amount of 0.64 pmol/cm2. If pretreatment is impractical, then the results may be scaled based on the tubing length necessary for constructing custom experimental equipment. It also may reabsorb 4He from the atmosphere in time. These studies also demonstrate that it is necessary to pretreat most materials prior to performing experiments where the presence of 4He is being used as an indicator for novel nuclear reactions.
{"title":"Exploring helium retention from technical materials: Development and investigation","authors":"Andrew K. Gillespie, Cuikun Lin, Django Jones, Sandeep Puri, R.V. Duncan","doi":"10.1016/j.net.2024.08.005","DOIUrl":"10.1016/j.net.2024.08.005","url":null,"abstract":"<div><div>Materials used to study nuclear fusion can retain atmospheric helium unless pretreated before an experiment. Understanding helium outgassing is important for accurate diagnostics in experiments surrounding nuclear fusion. The presence of helium is often cited as the primary evidence that a nuclear reaction has occurred, so it is imperative that known sources of helium are mitigated prior to proceeding with novel nuclear experiments. It is also necessary to ensure hermeticity when transferring gas aliquots from an experiment to a mass spectrometer. In this article, we present studies of helium leak rates in systems used in novel nuclear experiments. We also present studies of helium retention in materials subjected to various heating profiles and atmospheric concentrations. Without pretreatment, 12-inch lengths of both 3/8” diameter tubes and 1/2″ diameter stainless-steel 316 tubing yielded an average areal outgassing amount of 0.64 pmol/cm<sup>2</sup>. If pretreatment is impractical, then the results may be scaled based on the tubing length necessary for constructing custom experimental equipment. It also may reabsorb <sup>4</sup>He from the atmosphere in time. These studies also demonstrate that it is necessary to pretreat most materials prior to performing experiments where the presence of <sup>4</sup>He is being used as an indicator for novel nuclear reactions.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 1","pages":"Article 103136"},"PeriodicalIF":2.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207269","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}