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Preparation of Zr-Cu Coatings on Copper Substrate Using a Molten Salt Method

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Journal of Wuhan University of technology(Materials science) 2023年第5期38卷 1155-1160页

作者： LI Yusha ZHANG Yingchun LIU Yanhong LI Guangbin DONG Xiaoxun l.School of Materials science and Engineering University of Science and Technology BeijingBeijing 100083China state power investment corporation science and technology research institute Beijing 100029China

Dense zirconium coatings on copper substrates were obtained in an alumina crucible and a stainless steel crucible from FLiNaK-K_(2)ZrF_(6)molten salt at 1023 *** to the potential difierences between copper and zirconium,zirconium can difiuse into the copper substrate to form zirconium alloys on the surface of copper substrates in the course of *** coating deposited in a stainless steel crucible has a gray *** components of the coating are mainly CuZr2alloy and Cu_(10)Zr_(7)alloy,and,the outermost layer of the coating is a layer of amorphous pure *** coating deposited in an alumina crucible has a silvery white metallic *** components of the coating are mainly Cu-Zr-Al intermetallic compounds,AlCu_(2)Zr,ZrAl,AlCu and ***,two types of zirconium coatings can greatly increase the hardness of the substrate.

关键词： coating Zr-Cu molten salt intermetallic compounds

Transient analysis and optimization of passive residual heat removal heat exchanger in advanced nuclear power plant

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Nuclear science and Techniques 2022年第8期33卷 147-162页

作者： Yan-Bin Liu Xiang-Yu Meng Xue-Sheng Wang Qi-Ming Men Yu-Yang Yuan Jia-Ming Cao Key Laboratory of Pressure Systems and Safety Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Shanghai Nuclear Engineering research and Design institute State Power Investment CorporationShanghai 200233China

The transient performance and optimization of a passive residual heat removal heat exchanger(PRHR HX)were ***,a calculation method was developed for predicting the heat transfer of the PRHR *** calculation results were validated through comparisons with ROSA experimental *** heat-transfer performance of the AP1000 PRHR HX in the initial period was predicted,and it satisfied the design ***,the distributions of the heat flux,tube-inside/outside heattransfer coefficients,and heat load for the AP1000 PRHR HX over 2000 s were ***,an optimization study was conducted by adjusting the horizontal length and tube *** effects on the four main heat-transfer parameters and the heat-transfer area were ***,the influence of the initial in-containment refueling water storage tank(IRWST)temperature was investigated using an established simulation *** results indicated that it significantly affected the trends of the IRWST temperature and reactor outlet ***,the minimum required flow rates over time to maintain the reactor outlet temperature at the safety line were determined for different start-up *** trends of the minimum required flow rate and the peak flow rate were analyzed.

关键词： Heat transfer PRHR HX Transient analysis Optimization investigation

MeshCNN-based BREP to CSG conversion algorithm for 3D CAD models and its application

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Nuclear science and Techniques 2022年第6期33卷 75-88页

作者： Yue-Tong Luo Hua Du Yi-Man Yan Hefei University of technology Hefei 230009China University of science and technology of China Hefei 230027China institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China state power investment corporation research institute National Energy Key Laboratory of Nuclear Power SoftwareBeijing 102209China

In the field of neutronics analysis, it is imperative to develop computer-aided modeling technology for Monte Carlo codes to address the increasing complexity of reactor core components by converting 3D CAD model(boundary representation, BREP) to MC model(constructive solid geometry, CSG). Separation-based conversion from BREP to CSG is widely used in computer-aided modeling MC codes because of its high efficiency, reliability, and easy implementation. However, the current separation-based BREP-CSG conversion is poor for processing complex CAD models, and it is necessary to divide a complex model into several simple models before applying the separation-based conversion algorithm, which is time-consuming and tedious. To avoid manual segmentation, this study proposed a MeshCNN-based 3D-shape segmentation algorithm to automatically separate a complex model. The proposed 3D-shape segmentation algorithm was combined with separation-based BREP-CSG conversion algorithms to directly convert complex *** proposed algorithm was integrated into the computeraided modeling software cosVMPT and validated using the Chinese fusion engineering testing reactor model. The results demonstrate that the MeshCNN-based BREP-CSG conversion algorithm has a better performance and higher efficiency, particularly in terms of CPU time, and the conversion result is more intuitive and consistent with the intention of the modeler.

关键词： BREP to CSG conversion Computer-aided modeling cosVMPT Intelligent pre-segmentation MeshCNN

Application of homogenization techniques for inflow transport approximation on light water reactor analysis

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Nuclear science and Techniques 2022年第1期33卷 67-80页

作者： Xiang Xiao Kan Wang Tong-Rui Yang Yi-Xue Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China state power investment corporation research institute Co.LtdBeijing 100029China

The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering *** previous inflow transport approximation is based on the moderator cross-section and normalized fission source,which is approximated using transport *** the accuracy of reactivity is increased,the P0 flux moment has a large error in the Monte Carlo *** this study,an improved inflow transport approximation was introduced with homogenization techniques,applying the homogenized cross-section and accurate fission *** numerical results indicated that the improved inflow transport approximation can increase the P0 flux moment accuracy and maintain the reactivity calculation precision with the previous inflow transport approximation in typical LWR *** addition to this investigation,the improved inflow transport approximation is related to the temperature *** improved inflow transport approximation is flexible and accurate in the treatment of the anisotropic scattering effect,which can be directly used in the temperature-dependent nuclear data library.

关键词： Inflow transport approximation Anisotropic scattering effect Homogenization techniques Light water reactor

Effect of p H on the Electrochemical Behaviour and Passive FilmComposition of 316L Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2019年第5期32卷 585-598页

作者： Zhu Wang Zi-Qiang Zhou Lei Zhang Jia-Yuan Hu Zi-Ru Zhang Min-Xu Lu institute for Advanced Materials and technology University of Science and Technology Beijing state Grid Zhejiang Electric power research institute

The effect of pH on the electrochemical behaviour and passive film composition of 316 L stainless steel in alkaline solutions was studied using electrochemical measurements and a surface analysis method. The critical pH of 12.5 was found for the conversion from pitting corrosion to the oxygen evolution reaction(OER). OER was kinetically faster than pitting corrosion when both reactions could occur, and OER could postpone pitting corrosion. This resulted in pitting being initiated during the reversing scan in the cyclic polarization at the critical pH. According to the X-ray photoelectron spectroscopy analysis, the content of Cr and Mo decreased with pH, while Fe content increased. This induced the degradation of the passive film, which resulted in the higher passive current densities under more alkaline conditions. The selective dissolution of Mo at high p H was found, which demonstrated that the addition of Mo in austenitic stainless steels might not be beneficial to the corrosion resistance of 316L in strong alkaline solutions.

关键词： Stainless steel pH Polarization XPS Passive films

Corrosion Behavior and Mechanism of Irradiated 304 Nuclear Grade Stainless Steel in High-Temperature Water

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Acta Metallurgica Sinica(English Letters) 2021年第2期34卷 174-186页

作者： Ping Deng En-Hou Han Qunjia Peng Chen Sun CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear power institute of China Chengdu 610213China Suzhou Nuclear power research institute Suzhou 215004China state power investment corporation research institute Beijing 102209China

Corrosion behavior and mechanism of irradiated 304 nuclear grade stainless steel were studied in simulated pressurized water reactor primary *** microstructure of the oxide formed on the steel irradiated to different doses over an exposure period range of 25–1500 h was analyzed and *** was found that the general and intergranular corrosion rates of the steel were increased with irradiation dose,in correspondence with an evolution of the general oxide and the oxide formed at the grain *** of the oxide evolution with the corrosion kinetics and mechanism has been discussed in detail.

关键词： Stainless steel Irradiation High-temperature corrosion Intergranular corrosion

Proton irradiation assisted localized corrosion and stress corrosion cracking in 304 nuclear grade stainless steel in simulated primary PWR water

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Journal of Materials science & technology 2021年第6期65卷 61-71页

作者： Ping Deng Qunjia Peng En-Hou Han Wei Ke Chen Sun CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences.Shenyang 110016China Nuclear power institute of China Chengdu 610213China Suzhou Nuclear power research institute Suzhou 215004China state power investment corporation research institute Beijing 102209China

Localized deformation and corrosion in irradiated 304 nuclear grade stainless steel in simulated primary water were *** investigation was conducted by comparing the deformation structure,the oxide scale formed at the deformation structure,and their correlation with *** results revealed that increasing the irradiation dose promoted localized corrosion at the slip step and grain boundary,which was primarily attributed to the strain concentration induced by enhanced localized deformation and depletion of Cr at grain ***,a synergic effect of the enhanced localized deformation and localized corrosion at the slip step and grain boundary caused a higher cracking susceptibility of the irradiated steel.

关键词： Stainless steel AFM TEM High temperature corrosion Stress corrosion

Kinetics Characteristics and Bremsstrahlung of Argon DC Discharge Under Atmospheric Pressure

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Plasma science and technology 2013年第4期15卷 335-342页

作者：何为刘兴华咸日常陈素红廖瑞金杨帆肖汉光 state Key Laboratory of power Transmission Equipment & System Security and New technology Chongqing University Zibo power Supply Company Shandong Electric Power Corporation Shandong Electric power research institute Shandong Electric Power Corporation

An improved self-consistent, multi-component, and one-dimensional plasma model for simulating atmospheric pressure argon glow discharge is presented. In the model, both the plasma hydrodynamics model and chemical model are considered. The numerical simulation is carried out for parallel-plate geometry with a separation of 0.06 cm. The results show that Ar＊ plays a major role in the discharge, which is mainly produced by ground state excitation reaction. The electron temperature reaches its maximum in the cathode sheath but maintains a low value （0.23 eV） in bulk plasma. Elastic collision is the dominant volumetric electron energy loss in atmosphere argon glow discharge, which is negligible in low pressure argon glow discharge. The metastable step-wise ionization is the main mechanism for electron production to sustain the discharge. However, the highest contribution to electron production rate is ground state ionization reaction. The bremsstrahlung power density is related to electric voltage. With the increase of the electric voltage, the bremsstrahlung power density increases, namely, the strength of ultraviolet radiation spectrum enhances in the cathode sheath.

关键词： atmospheric pressure glow discharge plasma model metastable argon atom,ionization reaction bremsstrahlung power density

Stochastic convergence analysis of cubature Kalman filter with intermittent observations

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Journal of Systems Engineering and Electronics 2018年第4期29卷 823-833页

作者： SHI Jie QI Guoqing LI Yinya SHENG Andong School of Automation Nanjing University of Science and TechnologyNanjing 210094China NARI Group corporation/state Grid Electric power research institute Nanjing 211000China

The stochastic convergence of the cubature Kalmanfilter with intermittent observations （CKFI） for general nonlinearstochastic systems is investigated. The Bernoulli distributed ran-dom variable is employed to describe the phenomenon of intermit-tent observations. According to the cubature sample principle, theestimation error and the error covariance matrix （ECM） of CKFIare derived by Taylor series expansion, respectively. Afterwards, itis theoretically proved that the ECM will be bounded if the obser-vation arrival probability exceeds a critical minimum observationarrival probability. Meanwhile, under proper assumption corre-sponding with real engineering situations, the stochastic stabilityof the estimation error can be guaranteed when the initial estima-tion error and the stochastic noise terms are sufficiently small. Thetheoretical conclusions are verified by numerical simulations fortwo illustrative examples; also by evaluating the tracking perfor-mance of the optical-electric target tracking system implementedby CKFI and unscented Kalman filter with intermittent observa-tions （UKFI） separately, it is demonstrated that the proposed CKFIslightly outperforms the UKFI with respect to tracking accuracy aswell as real time performance.

关键词： cubature Kalman filter (CKF) intermittent observation estimation error stochastic stability.