检索结果-内蒙古大学图书馆

Research for the heat leakage caused by gaps on barrel insulation structure of reactor pressure vessel

International Journal of Advanced Nuclear reactor design and technology 2019年 1卷 30-42页

作者： Tian, Qiu Ying, Luo Yang, Qiu Yu-guang, Li Guo-fu, Xie Li-cai, Yang Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China ChengduSichuan Province610213 China

Due to the function requirements of the Cavity Injection and Cooling system, the barrel insulation structure of HPR1000 reactor pressure vessel has been greatly improved compared with the previous projects. In the past, the empirical formula method was used to evaluate the thermal properties of the insulation, but the influences of the support structure and the excessive gap on insulation are difficult to evaluate. In this paper, the fitting formula of the equivalent thermal conductivity and the qualitative temperature of the insulation have been obtained firstly through the heat transfer test. Then, ANSYS Fluent was used to simulate the barrel insulation structure with gaps of HPR1000. A circumferential 15° model was established to obtain evaluation method for flow leakage with gaps in hot state, and then a whole model of the barrel insulation structure with gaps was established to obtain heat loss of insulation based on calculation of flow leakage. The sensitivity of gap size and ventilation parameters to heat leakage was further analyzed. Finally, it was indicated that, by minimizing joint gap length, setting of overlaps, controlling cold gap, optimizing structure of insulation support, the effect of heat leakage caused by gaps can be reduced. © 2019 Xi'an Jiaotong University

关键词： Thermal insulation

来源：评论

学校读者我要写书评

暂无评论

Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation

引用

Nuclear science and Techniques 2024年第8期35卷 177-203页

作者： Li‑Zhan Hong He‑Lin Gong Hong‑Jun Ji Jia‑Liang Lu Han Li Qing Li Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy *** previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their *** study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these *** efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive *** methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational *** numerical results show that the hybrid KNNLHS algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 ***,algorithms such as FSA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management *** developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices.

关键词： Parameter identification State estimation reactor operation digital twin Reduced order model Inverse problem

来源：评论

学校读者我要写书评

暂无评论

Ratcheting Behavior of SA508-3 Steel at Elevated Temperature:Experimental Observation and Simulation

引用

Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 822-828页

作者： Jun Tian Yu Yang Li-Ping Zhang Xue-Jiao Shao Juan Du Qian-Hua Kan Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong University

A series of monotonic uniaxial tensile tests, strain-controlled and stress-controlled cyclic tests of SA508-3 steel were conducted from 25 to 350℃. Results showed that the steel exhibited temperature-dependent cyclic softening characteristic and obvious ratcheting behavior, and dynamic strain aging was observed in the range of 250-350℃. Based on experimental observations, a temperature-dependent cyclic plastic constitutive model was proposed by introducing the nonlinear cyclic softening and kinematic hardening rules, and the dynamic strain aging was also considered into the constitutive model. Comparisons between experiments and simulations were carded out to validate the proposed model at elevated temperature.

关键词： Ratcheting Constitutive model Dynamic strain aging Cyclic loading Elevated temperature

来源：评论

学校读者我要写书评

暂无评论

Atomistic study on the microscopic mechanism of grain boundary embrittlement induced by small dense helium bubbles in iron

引用

Nuclear science and Techniques 2024年第3期35卷 84-95页

作者： Lei Peng Yong-Jie Sun Jing-Yi Shi Yi-Fei Liu Shang-Ming Chen Liu-Liu Li State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

The helium bubbles induced by 14 MeV neutron irradiation can cause intergranular fractures in reduced activation ferritic martensitic steel,which is a candidate structural material for fusion *** order to elucidate the susceptibility of different grain boundaries(GBs)to helium-induced embrittlement,the tensile fracture processes of 10 types of GBs with and without helium bubbles in body-centered cubic(bcc)iron at the relevant service temperature of 600 K were investigated via molecular dynamics *** results indicate that in the absence of helium bubbles,the GBs studied here can be classified into two distinct categories:brittle GBs and ductile *** atomic scale analysis shows that the plastic deformation of ductile GB at high temperatures originates from complex plastic deformation mechanisms,including the Bain/Burgers path phase transition and deformation twinning,in which the Bain path phase transition is the most dominant plastic deformation ***,the presence of helium bubbles severely inhibits the plastic deformation channels of the GBs,resulting in a significant decrease in elongation at *** bubble-decorated GBs,the ultimate tensile strength increases with the increase in the misorientation ***,the coherent twin boundary∑3{112}was found to maintain relatively high fracture strength and maximum failure strain under the influence of helium bubbles.

关键词： Helium bubble Grain boundary Embrittlement Reduced activation ferritic martensitic steel Molecular dynamics Bain path

来源：评论

学校读者我要写书评

暂无评论

Effect of grain size on gas bubble evolution in nuclear fuel:Phase-field investigations

引用

Chinese Physics B 2024年第1期33卷 563-572页

作者：孙丹杨青峰赵家珺高士鑫辛勇周毅尹春雨陈平赵纪军王园园 Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China Key Laboratory of Materials Modification by Laser Ionand Electron BeamsDalian University of TechnologyDalian 116024China

Numerous irradiation-induced gas bubbles are created in the nuclear fuel during irradiation, leading to the change of microstructure and the degradation of mechanical and thermal properties. The grain size of fuel is one of the important factors affecting bubble evolution. In current study, we first predict the thermodynamic behaviors of point defects as well as the interplay between vacancy and gas atom in both UO_(2) and U_(3)Si_(2) according to ab initio approach. Then, we establish the irradiation-induced bubble phase-field model to investigate the formation and evolution of intra-and inter-granular gas bubbles. The effects of fission rate and temperature on the evolutions of bubble morphologies in UO_(2) and U_(3)Si_(2) have been revealed. Especially, a comparison of porosities under different grain sizes is examined and analyzed. To understand the thermal conductivity as functions of grain size and porosity, the heat transfer capability of U_(3)Si_(2) is evaluated.

关键词： grain size point defects fission gas bubble

来源：评论

学校读者我要写书评

暂无评论

Rapid diagnostic method for transplutonium isotope production in high flux reactors

引用

Nuclear science and Techniques 2023年第3期34卷 125-142页

作者： Qing-Quan Pan Qing-Fei Zhao Lian-Jie Wang Bang-Yang Xia Yun Cai Xiao-Jing Liu School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

Transplutonium isotopes are scarce and need to be produced by irradiation in high flux ***,their production is inefficient,and optimization studies are *** study analyzes the physical nature of transplutonium isotope produc-tion using ^(252)Cf,^(244)Cm,^(242)Cm,and ^(238)Pu as *** methods based on the Monte Carlo burnup calculation have the limitations of many calculations and cannot analyze the individual energy intervals in detail;thus,they cannot sup-port the refined evaluation,screening,and optimization of the irradiation *** understanding the physical nature and simplifying the complexity of the production process,we propose a rapid diagnostic method for evaluating radiation schemes based on the concepts“single energy interval value(SEIV)”and“energy spectrum total value(ESTV)”.The rapid diagnostic method not only avoids tedious burnup calculations,but also provides a direction for *** optimal irradiation schemes for producing ^(252)Cf,^(244)Cm,^(242)Cm,and ^(238)Pu are determined based on a rapid diagnostic *** irradiation schemes can significantly improve production *** with the initial scheme,the optimal scheme improved the production efficiency of ^(238)Pu by 7.41 times;^(242)Cm,11.98 times;^(244)Cm,65.20 times;and ^(252)Cf,15.08 ***,a refined analysis of transplutonium isotope production is conducted and provides a theoretical basis for improving production efficiency.

关键词： Transplutonium isotope Rapid diagnostic method Production optimization Single energy interval value Energy spectrum total value

来源：评论

学校读者我要写书评

暂无评论

High-resolution neutronics model for ^(238)Pu production in high-flux reactors

引用

Nuclear science and Techniques 2024年第5期35卷 226-236页

作者： Qing-Quan Pan Qing-Fei Zhao Lian-Jie Wang Bang-Yang Xia Yun Cai Jin-Biao Xiong Xiao-Jing Liu School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux *** filter burnup and single energy burnup methods have no theoretical approximation and can achieve a spectrum resolution of up to~1 eV,thereby constructing the importance curve and yield curve of the full energy *** burnup extreme analysis method combines the importance and yield curves to consider the influence of irradiation time on production efficiency,thereby constructing extreme *** three curves,which quantify the transmutation rate of the nuclei in each energy region,are of physical significance because they have similar distributions.A high-resolution neutronics model for ^(238)Pu production was established based on these three curves,and its universality and feasibility were *** neutronics model can guide the neutron spectrum optimization and improve the yield of ^(238)Pu by up to 18.81%.The neutronics model revealed the law of nuclei transmutation in all energy regions with high spectrum resolution,thus providing theoretical support for high-flux reactor design and irradiation production of ^(238)Pu.

关键词： ^(238)Pu Neutronics model High-flux reactor Spectrum resolution Spectrum optimization

来源：评论

学校读者我要写书评

暂无评论

CFD simulation of thermal hydraulic characteristics in a typical upper plenum of RPV

引用

Frontiers in Energy 2021年第4期15卷 930-945页

作者： Mingjun WANG Lianfa WANG Yingjie WANG Wenxi TIAN Jian DENG Guanghui SU Suizheng QI State Key Laboratory of Multiphase Flow in Power Engineering Department of Nuclear Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

A comparative computational fluid dynamics(CFD)study was conducted on the three different types of pressurized water reactor(PWR)upper plenum,named TYPE 1(support columns(SCs)and control rod guide tubes(CRGTs)with two large windows),TYPE 2(SCs and CRGTs without windows),and TYPE 3(two parallel perforated barrel shells and CRGTs).First,three types of upper plenum geometry information were collected,simplified,and adopted into the BORA facility,which is a 1/5 scale system of the four-loop PWR ***,the geometry,including the upper half core,upper plenum region,and hot legs,was built using the Salome *** that,an unsteady calculation to simulate the reactor balance operation at hot full power scenario was ***,the differences of flowrate distribution at the core outlet and temperature distribution and transverse velocity inside the hot legs with different upper plenum internals were *** results suggest that TYPE 1 upper plenum internals cause the largest flowrate difference at the core outlet while TYPE 3 leads to the most even distributed *** distribution and evolution pattern of the tangential velocity inside hot legs is highly dependent on the upper plenum *** counter-rotating swirls exist inside the TYPE 1 hot leg and only one swirl revolving around the hog leg axis exist inside the TYPE 2 hot *** TYPE 3,two swirls like that of TYPE 1 rotating around the hot leg axis significantly increase the temperature homogenization *** research provides meaningful guidelines for the future optimization and design of advanced PWR upper plenum internal structures.

关键词： pressurized water reactor(PWR) upper plenum internal structures temperature distribution computational fluid dynamics(CFD)

来源：评论

学校读者我要写书评

暂无评论

Microstructure and Mechanical Properties of B-Bearing Austenitic Stainless Steel Fabricated by Laser Metal Deposition In-Situ Alloying

引用

Acta Metallurgica Sinica(English Letters) 2022年第3期35卷 453-465页

作者： Sheng Huang Xiaoyu Zhang Dichen Li Qingyu Li State Key Laboratory for Manufacturing Systems Engineering Xian Jiaotong UniversityXian 710049China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

In the field repair application of laser metal deposition(LMD),the kinds of powder materials that can be used are limited,while the equipment components are made of various *** many components have to be repaired with heterogeneous ***,it is difficult to match the mechanical properties between the repaired layer and the substrate due to the diff erent *** on the high flexibility of raw materials and processes in LMD,an in-situ alloying method is proposed herein for tailoring the mechanical properties of LMDed *** diff erent mixing ratios of Fe314 and 316 L stainless steel powders as the control parameter,the microstructure and mechanical properties of B-bearing austenitic stainless steel fabricated by LMD in-situ alloying with diff erent proportions of Fe314 and 316 L particles were *** the increase in the concentration of 316 L steel,the volume fraction of the eutectic phase in deposited B-bearing austenitic stainless steel reduced,the size of the austenite dendrite increased,the yield strength and ultimate tensile strength decreased monotonically,while the elongation increased ***,the fracture mode changed from quasi-cleavage fracture to ductile *** adding 316 L powder,the yield strength,tensile strength,and elongation of deposited B-bearing austenitic stainless steel could be adjusted within the range of 712 MPa–257 MPa,1325 MPa–509 MPa,and 8.7%–59.3%,***,this work provides a new method and idea for solving the performance matching problem of equipment components in the field repair.

关键词： Additive manufacturing Laser metal deposition In-situ alloying B-bearing austenitic stainless steel Mechanical properties

来源：评论

学校读者我要写书评

暂无评论

Analysis of contribution degree of vibration transmission of bolted structure 29

Analysis of contribution degree of vibration transmission of...

引用

2022 29th International Conference on Nuclear Engineering, ICONE 2022

作者： Liu, Shuai Li, Wanyou Huang, Xuan Xiong, Furui Jiang, Xiaozhou Deng, Dliwei Harbin Engineering University Harbin China Science and Technology on Reactor System Design Technology Laboratory Chengdu China Technology on Reactor System Design Technology Laboratory Chengdu China

ISBN: (纸本)9780791886359

In practical engineering, the vibration transmission between bolted structures supported by cantilever beams involves many factors, including the friction between plates and the bolt connection relationship. The vibration transmission effect is the embodiment of the coupling of various factors, so it is impossible to accurately and quantitatively evaluate the influence degree of various factors. In this paper, the influence factors of vibration between bolted plates in the form of cantilever beam are studied by numerical calculation method. The effects of friction coefficient, bolt preload, temperature and internal and external pressure on vibration characteristics are studied. Finally, the contribution of different influencing factors to vibration transmission is given. The preliminary research shows that the bolt connects the two plates into a whole structure, and its stiffness changes little with the friction coefficient, bolt preload, temperature and internal and external pressure. The natural frequency of each order increases with the increase of friction coefficient, bolt preload and internal and external pressure, decreases with the increase of temperature, and the overall trend changes little. At the same time, the bolt preload is verified by test, the difference of natural frequency under the same preload is compared and analyzed, the numerical calculation is compared with the test value, and the vibration contribution of preload is verified. © 2022 American Society of Mechanical Engineers (ASME). All rights reserved.

关键词： Cantilever beams

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：