Pub Date : 2025-02-01DOI: 10.1016/j.net.2024.09.010
Dokyun Kim, Seong Jeong Jeong, Hyung Jin Shim
The 5 MWe graphite-moderated gas-cooled reactor located at Yongbyon, North Korea, is a major facility for producing nuclear materials. The objective of this study is to evaluate the tritium production capability of the 5 MWe reactor when using a tritium-producing burnable absorber rod (TPBAR). This paper presents burnup analysis results for TPBAR-embedded core models performed by McCARD, a Monte Carlo neutron transport simulation code. For three types of cores with TPBARs, the numerical results show that the 5 MWe reactor can produce 1.83–7.51 g of tritium per year depending on the number of TPBARs in the core. The numerical results can serve as a basis for assessing the feasibility of producing tritium using graphite-moderated gas-cooled reactors.
{"title":"Evaluation of tritium production capability of the 5 MWe gas-cooled graphite-moderated reactor at Yongbyon using tritium-producing burnable absorber rods","authors":"Dokyun Kim, Seong Jeong Jeong, Hyung Jin Shim","doi":"10.1016/j.net.2024.09.010","DOIUrl":"10.1016/j.net.2024.09.010","url":null,"abstract":"<div><div>The 5 MWe graphite-moderated gas-cooled reactor located at Yongbyon, North Korea, is a major facility for producing nuclear materials. The objective of this study is to evaluate the tritium production capability of the 5 MWe reactor when using a tritium-producing burnable absorber rod (TPBAR). This paper presents burnup analysis results for TPBAR-embedded core models performed by McCARD, a Monte Carlo neutron transport simulation code. For three types of cores with TPBARs, the numerical results show that the 5 MWe reactor can produce 1.83–7.51 g of tritium per year depending on the number of TPBARs in the core. The numerical results can serve as a basis for assessing the feasibility of producing tritium using graphite-moderated gas-cooled reactors.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103207"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099939","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.2024.08.045
Dayang Wang , Qiang Liu , Yuanqi Song , Yong Zhu , Yongshan Zhang
This paper presents an innovative design of a steel-reinforced concrete (SRC) column-reinforced concrete (RC) slab joint based on a concept of the strong column and weak slab. In this study, two 1:2 reduced scale SRC column-RC slab joint specimens are designed and fabricated for horizontal cyclic loading tests based on side slab-column joints of an auxiliary plant of a nuclear power plant. In order to ensure the ease of construction and stability of the connection between the reinforcement and the section steel, one structure (SR-2) with steel sleeves welded to the section steel and connected to the reinforcement in the joint area and the other structure (SR-1) with a stiffened steel plate (SSP) in the connection area on the basis of SR-2 were fabricated and tested in order to investigate the structural strengthening the joint. Based on the test results, the damage modes, hysteresis performance, energy dissipation capacity and stiffness degradation of the specimens were studied. A finite element analysis (FEA) model was developed and verified with the experimental results. The verified FEA model was used for parametrical study on effects of thickness, outer dimensions of SSP, a longitudinal reinforcement ratio in the RC slab and an axial pressure ratio. The test results show that the damage mode of specimens is shear failure at the RC slab and the damage of the SRC column is minor, which is in line with the design concept of the strong column and weak slab. The parametric study shows that increasing the thickness and outer size of SSP can improve the load-bearing capacity and initial stiffness of joints.
{"title":"Experimental and numerical study on seismic behaviors of SRC column-RC slab joints in NPP","authors":"Dayang Wang , Qiang Liu , Yuanqi Song , Yong Zhu , Yongshan Zhang","doi":"10.1016/j.net.2024.08.045","DOIUrl":"10.1016/j.net.2024.08.045","url":null,"abstract":"<div><div>This paper presents an innovative design of a steel-reinforced concrete (SRC) column-reinforced concrete (RC) slab joint based on a concept of the strong column and weak slab. In this study, two 1:2 reduced scale SRC column-RC slab joint specimens are designed and fabricated for horizontal cyclic loading tests based on side slab-column joints of an auxiliary plant of a nuclear power plant. In order to ensure the ease of construction and stability of the connection between the reinforcement and the section steel, one structure (SR-2) with steel sleeves welded to the section steel and connected to the reinforcement in the joint area and the other structure (SR-1) with a stiffened steel plate (SSP) in the connection area on the basis of SR-2 were fabricated and tested in order to investigate the structural strengthening the joint. Based on the test results, the damage modes, hysteresis performance, energy dissipation capacity and stiffness degradation of the specimens were studied. A finite element analysis (FEA) model was developed and verified with the experimental results. The verified FEA model was used for parametrical study on effects of thickness, outer dimensions of SSP, a longitudinal reinforcement ratio in the RC slab and an axial pressure ratio. The test results show that the damage mode of specimens is shear failure at the RC slab and the damage of the SRC column is minor, which is in line with the design concept of the strong column and weak slab. The parametric study shows that increasing the thickness and outer size of SSP can improve the load-bearing capacity and initial stiffness of joints.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103176"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207231","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.2024.08.054
Amruta Pasarkar, S. Balaguru
In sodium-cooled fast reactors (SFR), 316L(N) SS grid plate is hardfaced with Ni-Cr-B-Si alloy to achieve higher wear resistance. Tensile and fatigue forces are acting at the interface between substrate and deposit due to different thermal expansion coefficients of those two materials, which can cause cracking of deposit and fracture during operation. Thus, it is very important to consider appropriate hardfacing method which can provide higher tensile and fatigue strength to avoid cracking/debonding at the interface. To find a solution to this problem, two hardfacing techniques, namely Gas Tungsten Arc (GTA) and Laser cladding (LC), are taken into consideration. Hardfaced specimens are prepared using each process on which tensile and high cycle fatigue tests are conducted. From the experimental testing, stress-strain and S-N curves are generated to predict the tensile and fatigue behaviour of specimens. Fractographic studies are conducted at fractured surfaces to understand the fatigue crack nucleation and propagation characteristics. The experimental results for both processes are compared. Tensile and fatigue strength of LC specimens are ∼11 % and ∼17 % less than those of GTA specimens due to its higher brittleness. Thus, GTA process is recommended as the efficient hardfacing process for grid plate of SFR.
{"title":"Comparative study on tensile and high cycle fatigue behaviour of 316L(N) SS hardfaced with Ni-Cr-B-Si alloy by GTA and laser cladding processes","authors":"Amruta Pasarkar, S. Balaguru","doi":"10.1016/j.net.2024.08.054","DOIUrl":"10.1016/j.net.2024.08.054","url":null,"abstract":"<div><div>In sodium-cooled fast reactors (SFR), 316L(N) SS grid plate is hardfaced with Ni-Cr-B-Si alloy to achieve higher wear resistance. Tensile and fatigue forces are acting at the interface between substrate and deposit due to different thermal expansion coefficients of those two materials, which can cause cracking of deposit and fracture during operation. Thus, it is very important to consider appropriate hardfacing method which can provide higher tensile and fatigue strength to avoid cracking/debonding at the interface. To find a solution to this problem, two hardfacing techniques, namely Gas Tungsten Arc (GTA) and Laser cladding (LC), are taken into consideration. Hardfaced specimens are prepared using each process on which tensile and high cycle fatigue tests are conducted. From the experimental testing, stress-strain and S-N curves are generated to predict the tensile and fatigue behaviour of specimens. Fractographic studies are conducted at fractured surfaces to understand the fatigue crack nucleation and propagation characteristics. The experimental results for both processes are compared. Tensile and fatigue strength of LC specimens are ∼11 % and ∼17 % less than those of GTA specimens due to its higher brittleness. Thus, GTA process is recommended as the efficient hardfacing process for grid plate of SFR.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103185"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207225","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.2024.09.006
Dana Hejazi , Anas M. Alwafi , Salman M. Alzahrani , Meshari M. Alqahtani , Salman M. Alshehri
Molten Salt Reactors (MSRs) represent a promising, safe, advanced nuclear technology that aligns with Saudi Arabia’s Vision 2030 objectives for energy diversification, sustainability, and economic development. This article explores the feasibility and potential impact of implementing MSRs in the Kingdom by assessing some of their technical, environmental, and socio-economic aspects. The research findings indicate that while MSRs may require higher initial capital investments, they offer substantial long-term socio-economic and environmental advantages over conventional power generation technologies. Economic advantages stem from improved fuel efficiency, lower waste management costs, fuel flexibility, load following, job creation, and operational cost savings. Environmental advantages include clean energy production, the ability to utilize thorium as a more environmentally friendly fuel source, the potential of nuclear transmutation for minimizing long-lived radioactive waste, and overall reduced waste output compared to traditional nuclear reactors. While implementing MSRs requires overcoming technical hurdles, mainly related to structural materials withstanding extreme conditions, Saudi Arabia’s thriving research ecosystem is well-suited for overcoming such challenges. The adoption of MSRs presents an opportunity for groundbreaking research, economic diversification, and progression towards a sustainable energy future. With rising energy demands and the need to transition towards cleaner sources, nuclear energy is poised to play a vital role globally and in Saudi Arabia’s future energy mix. This article hopes to raise awareness about the potential of advanced nuclear technologies like MSRs and inspire further research, investment, and conversation within the Kingdom to capitalize on this promising opportunity.
{"title":"The small modular molten salt reactor potential and opportunity in Saudi Arabia","authors":"Dana Hejazi , Anas M. Alwafi , Salman M. Alzahrani , Meshari M. Alqahtani , Salman M. Alshehri","doi":"10.1016/j.net.2024.09.006","DOIUrl":"10.1016/j.net.2024.09.006","url":null,"abstract":"<div><div>Molten Salt Reactors (MSRs) represent a promising, safe, advanced nuclear technology that aligns with Saudi Arabia’s Vision 2030 objectives for energy diversification, sustainability, and economic development. This article explores the feasibility and potential impact of implementing MSRs in the Kingdom by assessing some of their technical, environmental, and socio-economic aspects. The research findings indicate that while MSRs may require higher initial capital investments, they offer substantial long-term socio-economic and environmental advantages over conventional power generation technologies. Economic advantages stem from improved fuel efficiency, lower waste management costs, fuel flexibility, load following, job creation, and operational cost savings. Environmental advantages include clean energy production, the ability to utilize thorium as a more environmentally friendly fuel source, the potential of nuclear transmutation for minimizing long-lived radioactive waste, and overall reduced waste output compared to traditional nuclear reactors. While implementing MSRs requires overcoming technical hurdles, mainly related to structural materials withstanding extreme conditions, Saudi Arabia’s thriving research ecosystem is well-suited for overcoming such challenges. The adoption of MSRs presents an opportunity for groundbreaking research, economic diversification, and progression towards a sustainable energy future. With rising energy demands and the need to transition towards cleaner sources, nuclear energy is poised to play a vital role globally and in Saudi Arabia’s future energy mix. This article hopes to raise awareness about the potential of advanced nuclear technologies like MSRs and inspire further research, investment, and conversation within the Kingdom to capitalize on this promising opportunity.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103203"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226263","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.2024.08.059
Yue Zhang , Ruirui Xu , Yuan Tian , Haicheng Wu , Xichao Ruan , Yinlu Han , Huanyu Zhang , Ping Liu , Xi Tao , Zhi Zhang , Changlin Lan , Xiaodong Sun , Yongli Jin , Nengchuan Shu , Jimin Wang , Xiaolong Huang , Zhigang Ge
In order to improve the quality of neutron data for 238U in CENDL, considering the impact of new measurements, a brand-new evaluation of the complete set of neutron induced 238U reaction data up to 20 MeV has been performed. Important reactions, such as (n,tot), (n,γ), (n,f), (n,2n) and (n,3n) reaction cross sections and average number of fission neutrons have been evaluated based on experimental data analysis. Also, using existing optical model potential parameters, new theoretical calculations based on Hauser-Feshbach and pre-equilibrium model have been carried out. Resonance parameters and prompt fission neutron spectrum from ENDF/B-VIII.0 have been adopted. Guided by integral benchmark, (n,inl), (n,γ) and (n,f) reaction cross sections have undergone multiple adjustments, leading to a noticeable improvement in data quality, as indicated by final benchmark results.
{"title":"Evaluations and calculations of neutron reactions on 238U up to 20 MeV","authors":"Yue Zhang , Ruirui Xu , Yuan Tian , Haicheng Wu , Xichao Ruan , Yinlu Han , Huanyu Zhang , Ping Liu , Xi Tao , Zhi Zhang , Changlin Lan , Xiaodong Sun , Yongli Jin , Nengchuan Shu , Jimin Wang , Xiaolong Huang , Zhigang Ge","doi":"10.1016/j.net.2024.08.059","DOIUrl":"10.1016/j.net.2024.08.059","url":null,"abstract":"<div><div>In order to improve the quality of neutron data for <sup>238</sup>U in CENDL, considering the impact of new measurements, a brand-new evaluation of the complete set of neutron induced <sup>238</sup>U reaction data up to 20 MeV has been performed. Important reactions, such as (n,tot), (n,γ), (n,f), (n,2n) and (n,3n) reaction cross sections and average number of fission neutrons have been evaluated based on experimental data analysis. Also, using existing optical model potential parameters, new theoretical calculations based on Hauser-Feshbach and pre-equilibrium model have been carried out. Resonance parameters and prompt fission neutron spectrum from ENDF/B-VIII.0 have been adopted. Guided by integral benchmark, (n,inl), (n,γ) and (n,f) reaction cross sections have undergone multiple adjustments, leading to a noticeable improvement in data quality, as indicated by final benchmark results.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103190"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207219","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.2024.08.052
Almog Biton , Evgeny Rabinovich , Erez Gilad
This work presents an experimental study of five threshold velocities for air-water flow in three different vertical channels. The measured threshold velocities included onset flooding (OF), end flooding (EF), onset deflooding (OD), end deflooding (ED), and minimum pressure (MP) velocities. The experimental system includes a transparent vertical tube of 52.5 mm inner diameter and 1500 mm length. The test channel can be easily changed from a tube to an annular shape by inserting a cylindrical test element. A counter-current or concurrent upward flow was achieved by blowing air upward from the channel's bottom and flowing water from its top. The threshold velocities were determined by analyzing the pressure drop versus air superficial velocity. Findings revealed evident hysteresis between the end flooding and onset deflooding velocities. In contrast, the end deflooding and onset flooding velocities were found to be identical. The end flooding velocity was indifferent to the water's superficial velocity for all three channel geometries. A generalized gas-liquid flow state diagram for vertical channels is developed based on the present empirical analysis for different threshold velocities.
{"title":"Experimental investigation of threshold velocities for air-water two-phase flow in a vertical tube and annular channels","authors":"Almog Biton , Evgeny Rabinovich , Erez Gilad","doi":"10.1016/j.net.2024.08.052","DOIUrl":"10.1016/j.net.2024.08.052","url":null,"abstract":"<div><div>This work presents an experimental study of five threshold velocities for air-water flow in three different vertical channels. The measured threshold velocities included onset flooding (OF), end flooding (EF), onset deflooding (OD), end deflooding (ED), and minimum pressure (MP) velocities. The experimental system includes a transparent vertical tube of 52.5 mm inner diameter and 1500 mm length. The test channel can be easily changed from a tube to an annular shape by inserting a cylindrical test element. A counter-current or concurrent upward flow was achieved by blowing air upward from the channel's bottom and flowing water from its top. The threshold velocities were determined by analyzing the pressure drop versus air superficial velocity. Findings revealed evident hysteresis between the end flooding and onset deflooding velocities. In contrast, the end deflooding and onset flooding velocities were found to be identical. The end flooding velocity was indifferent to the water's superficial velocity for all three channel geometries. A generalized gas-liquid flow state diagram for vertical channels is developed based on the present empirical analysis for different threshold velocities.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103183"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207224","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.2024.08.048
Eunwoo Lee , Taewoo Nam , Daniel Hernandez , Donghyuk Kim , Yeunchul Ryu , Yeji Han , Kyoung-Nam Kim
The specific absorption rate (SAR) substantially contributes to the elevation of patient temperatures during magnetic resonance imaging (MRI) scans, potentially leading to tissue degeneration and damage. In particular, the relatively short wavelength of radio frequency (RF) used in ultra-high field (UHF)-MRI generates non-uniform RF excitation (|B1+|) and electric (|E|)-fields within the body, with the potential to cause localized increases in tissue temperature. This study employs electromagnetic (EM) simulations to quantitatively assesses variations in SAR resulting from different patient's head positions across three types of RF coils (birdcage coil, loop array coil, and dipole array coil), frequently employed as transmission/reception (Tx/Rx) coils in 7 T MRI. Through analysis of 715 SAR values per RF coil, achieved by varying patient's head positions at 5 mm intervals within the maximum range of movement, the study shows substantial changes in SAR values averaged over 10 g of tissue (SAR10g). Notably, these changes reach a maximum difference of 339.89 % and 371.13 % in comparison to the iso-center (no change), concerning global- and local-SAR10g. Interestingly, the study identifies instances where SAR values surpass the standard SAR limit suggested by the safety guidelines, even when the distance between the RF coil and the patient exceeded 10 mm.
{"title":"Patient's head position-dependent safety analysis of birdcage coil, loop array, and dipole array for applications at 300 MHz in magnetic resonance imaging based on hydrogen nuclei: Simulation study","authors":"Eunwoo Lee , Taewoo Nam , Daniel Hernandez , Donghyuk Kim , Yeunchul Ryu , Yeji Han , Kyoung-Nam Kim","doi":"10.1016/j.net.2024.08.048","DOIUrl":"10.1016/j.net.2024.08.048","url":null,"abstract":"<div><div>The specific absorption rate (SAR) substantially contributes to the elevation of patient temperatures during magnetic resonance imaging (MRI) scans, potentially leading to tissue degeneration and damage. In particular, the relatively short wavelength of radio frequency (RF) used in ultra-high field (UHF)-MRI generates non-uniform RF excitation (|B<sub>1</sub><sup>+</sup>|) and electric (|E|)-fields within the body, with the potential to cause localized increases in tissue temperature. This study employs electromagnetic (EM) simulations to quantitatively assesses variations in SAR resulting from different patient's head positions across three types of RF coils (birdcage coil, loop array coil, and dipole array coil), frequently employed as transmission/reception (Tx/Rx) coils in 7 T MRI. Through analysis of 715 SAR values per RF coil, achieved by varying patient's head positions at 5 mm intervals within the maximum range of movement, the study shows substantial changes in SAR values averaged over 10 g of tissue (SAR<sub>10g</sub>). Notably, these changes reach a maximum difference of 339.89 % and 371.13 % in comparison to the iso-center (no change), concerning global- and local-SAR<sub>10g</sub>. Interestingly, the study identifies instances where SAR values surpass the standard SAR limit suggested by the safety guidelines, even when the distance between the RF coil and the patient exceeded 10 mm.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103179"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099928","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.2024.09.023
Jang Min Park , Kukhee Lim
Under severe accident conditions of nuclear power plants, the lower head of a reactor pressure vessel can be at risk of creep deformation and potential failure. This study presents a computational model that can represent the creep deformation of the lower head through the application of shell theory. To account for the large deformation due to creep, kinematic equations are derived and implemented. Particularly, this study provides details of the mathematical formulation, which were lacking in previous studies. The analysis results using the developed model are compared with those of finite element analysis, considering deformation history, stress distribution, and deformed shape. A dimensionless time for the creep deformation is proposed based on the results, which can characterize the effective strain at failure. Finally, the developed model is applied to OECD lower head failure test for validation.
{"title":"Development of axisymmetric shell model for creep deformation analysis of reactor pressure vessel lower head","authors":"Jang Min Park , Kukhee Lim","doi":"10.1016/j.net.2024.09.023","DOIUrl":"10.1016/j.net.2024.09.023","url":null,"abstract":"<div><div>Under severe accident conditions of nuclear power plants, the lower head of a reactor pressure vessel can be at risk of creep deformation and potential failure. This study presents a computational model that can represent the creep deformation of the lower head through the application of shell theory. To account for the large deformation due to creep, kinematic equations are derived and implemented. Particularly, this study provides details of the mathematical formulation, which were lacking in previous studies. The analysis results using the developed model are compared with those of finite element analysis, considering deformation history, stress distribution, and deformed shape. A dimensionless time for the creep deformation is proposed based on the results, which can characterize the effective strain at failure. Finally, the developed model is applied to OECD lower head failure test for validation.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103220"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099938","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.2024.09.007
Chong Zhang , Yongmei Li , Yuqing Niu , Kaixuan Tan , Tingting Xie , Yixuan Yao , Chunguang Li , Zhenzhong Liu
The leaching range is critical to the leaching efficiency, production cost and environmental effect of in-situ leaching of uranium. In this study, the groundwater dynamics of the well-site was simulated to determine the leaching range in condition of different process parameters (such as drilling space and the pumping-injection ratio), in addition, the control factors and evolution rules of the leaching boundary were explored. The results show that there is an obvious water level trough, i.e., the “stagnation point”, outside the injection hole of the well-site of in-situ leaching. The hydraulic gradient of the stagnation point is zero, which indicates that the leaching solution can migrate the farthest to stagnation point outside the well. Therefore, the connection line of all the stagnation points quantitatively determines the outer boundary of the leaching range from the perspective of hydrodynamics. Reducing the spacing of borehole can increase the drawdown of groundwater, and slightly increase the distance between the stagnation point and the edge injection well, i.e., the outer boundary of the leaching range. However, increasing the pumping-injection ratio would significantly reduce the outer boundary of the leaching range.
{"title":"Quantitative determination of the leaching range of in-situ leaching mining area by stagnation point","authors":"Chong Zhang , Yongmei Li , Yuqing Niu , Kaixuan Tan , Tingting Xie , Yixuan Yao , Chunguang Li , Zhenzhong Liu","doi":"10.1016/j.net.2024.09.007","DOIUrl":"10.1016/j.net.2024.09.007","url":null,"abstract":"<div><div>The leaching range is critical to the leaching efficiency, production cost and environmental effect of in-situ leaching of uranium. In this study, the groundwater dynamics of the well-site was simulated to determine the leaching range in condition of different process parameters (such as drilling space and the pumping-injection ratio), in addition, the control factors and evolution rules of the leaching boundary were explored. The results show that there is an obvious water level trough, i.e., the “stagnation point”, outside the injection hole of the well-site of in-situ leaching. The hydraulic gradient of the stagnation point is zero, which indicates that the leaching solution can migrate the farthest to stagnation point outside the well. Therefore, the connection line of all the stagnation points quantitatively determines the outer boundary of the leaching range from the perspective of hydrodynamics. Reducing the spacing of borehole can increase the drawdown of groundwater, and slightly increase the distance between the stagnation point and the edge injection well, i.e., the outer boundary of the leaching range. However, increasing the pumping-injection ratio would significantly reduce the outer boundary of the leaching range.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 2","pages":"Article 103204"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099578","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号