bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental Investigation on Natural Circulation Characteristics of Core Make-Up Tank Under Rolling Conditions
Authors: Wang Shuguang , Zhang Jinlei , Shen Ya'ou , Liu Xiaobo , Ding Shuhua , Liu Yusheng , Li Dongyang , Tang Jilin 
Published: November 2022

Abstract
In the floating nuclear power plant, Core Make-up Tank (CMT) is one of the passive safety facilities, has been widely used in nuclear engineering. Under emergency conditions, natural circulation occurs and consequent thermal stratification appears in CMT system. However, rolling motion will directly affect the natural circulation and destroy the formation of thermal stratification, so there will be uncertain and unknown change of the safety injection capacity of CMT. Based on above analysis, this work carried out experiments under rolling conditions to reveal natural circulation and thermal stratification characteristics in CMT. A temperature detecting matrix formed by thermocouples is deployed in CMT. It is concluded that thermal stratification distribution is affected by the rolling conditions. Rolling conditions increase the thickness of thermal stratification and reduce the temperature gradient. The CMT natural circulation has two stages, the influence of rolling motion on the average flow in the first stage of natural circulation is very weak, but rolling motion will significantly affect the second stage of natural circulation and advance the decline time of direct vessel injection (DVI) flow rate. The transition time of natural circulation stage and the flow change in the second stage of natural circulation are related to the thermal stratification in CMT. The impact of rolling conditions should not be ignored when evaluating the performance of CMT.
Microstructure, Texture and Mechanical Properties in Different Deformation Regions of the Compressed Zr-4 Alloy With Lamellar Structure
Authors: Ren Jie , Li Geping , Yuan Fusen , Wang Ben , Han Fuzhou , Ali Muhammad , Zhang Yingdong , Guo Wenbin , Gao Bo 
Published: November 2022

Abstract
In the present work, the inhomogeneous plastic deformation of the compressed Zr-4 alloy with lamellar structure has been studied systematically. In the compression test of Zr-4 alloy with reduction of 70% at 650°C, the severe deformed area (SDA) and difficult deformed area (DDA) formed. The differences in DDA and SDA including microstructure, texture, and mechanical properties were investigated, using electron backscattering diffraction (EBSD) and Vickers hardness tester. The results showed that a large number of equiaxed grains appeared in SDA due to the occurrence of dynamic recrystallization (DRX), while coarse lamellar grains were still the main microstructure in DDA, showing that the DDA was the intermediate between the initial alloy and SDA. Furthermore, the discontinuous recrystallization mechanism was proposed. According to electron backscattered diffraction (EBSD) analysis, the predominant texture formed in SDA and DDA made normal direction of its {0001} planes of α phase parallel to the compression direction, and another stronger texture in SDA made the normal direction of part {0001} planes ∼15° away from the compression direction. The observed texture difference in SDA and DDA mainly resulted from the DRXed grains. To evaluate the influence of SDA on the mechanical properties of the Zr-4 alloy, microhardness tests were employed. The alloy in SDA had been proved to be strengthened compared to DDA, which was due to both the grain refinement and the texture diversity.
Optimizing Material/Component Fabrication Processing for Improving Service Performance in Nuclear Power Plant Coolants
Authors: Lu Zhanpeng 
Published: November 2022

Abstract
The service performances in terms of stress corrosion cracking (SCC) of pressurized water reactor structural components in coolants are critical for the economic and long-term safe operation. the materials, microstructual and mechanical properties resulting from material manufacturing and component fabrication are strongly affecting their performance behaviors such as environmentally assisted cracking. The integrated route for achieving high service performance materials and components is proposed. Some cases of reports on the plant experiences of using cracking-sensitive or cracking-resistant materials are used to illustrated the importance of the route. The route is practiced and demonstrated to be effective through our cooperative R&D works with designers, materials producers, component venders, operating service organizations as well as industrial research institutes.
A Two-Phase Flow Computation Code Based on Two-Fluid Seven-Equation Model
Authors: Zhang Hao , Yang Yanhua 
Published: November 2022

Abstract
The present work is developing a computation code based on two-fluid seven-equation model. This model is fully non-equilibrium. It not only assumes two phases are mechanical and thermal non-equilibrium, but also it assumes the pressure is non-equilibrium. The governing equations include seven partial differential equations, which are two continuity equations, two momentum equations, two energy equations, and one volume fraction evolution equation. The computation framework is based on split scheme, including Godunov split and Strang split, and the problem is split into two independent subproblems. One is a homogenous partial differential equation (PDE) problem, and the other one is an ordinary differential equation (ODE) problem. The homogenous PDE problem is reduced to linear equation by a Roe-type Riemann solver, and the linear equation is solved by upwind and MUSCL-Hancock (MHM) scheme. The ODE problem is solved by an implicit ODE solver, including Euler backward method, trapezium rule method and TR-BDF2. This code is verified by three types of problems. MHM converges faster than upwind for smooth solution problem, however MHM’s convergency rate is not always large than that of upwind for shock problem. The source term problem shows that the calculation result is sensitivity to the numerical schemes.
Study on Simulation Test of Hydrogen Deflagration Environment In Nuclear Power Plants
Authors: Zhan Huian , Jiang Shaokun , Tao Zhiyong , Zhao Ning , Yuan Shengnan 
Published: November 2022

Abstract
The safety control of hydrogen is a key safety issue that must be considered in the design of nuclear power plant. In order to better study the impact of hydrogen combustion and even deflagration on the nuclear power plant, the Handan Purification Equipment Research Institute has designed and built a hydrogen deflagration environment simulation test platform, which can simulate the deflagration process of mixed gas with high hydrogen concentration range. The test results show that there are some differences in the hydrogen deflagration process of test container with different volumes. The large volume test container is more in line with the change process of hydrogen deflagration environment in serious accidents of nuclear power plant. The large volume test container has problems such as large concentration gradient of hydrogen and temperature stratification. The closer to the top of the test container, the higher the temperature. It is possible to select a suitable location to install the test equipment according to the needs. With the same gas composition conditions, increasing the initial mixture temperature can effectively improve the half peak width of the hydrogen deflagration ambient temperature curve and slow down the temperature decline rate in the simulated environment. The above experimental research lays a foundation for the equipment availability verification test in the hydrogen deflagration environment of nuclear power plant.
Design Overview for Process System of Large-Scale Seawater Desalination and Demineralized Water Production in the Nuclear Heating Plant
Authors: Wang Rui , Xu Kechen , Zeng Kehao , Yan Hongmei , Bai Wei , Li Jing 
Published: November 2022

Abstract
A nuclear heating plant is a cogeneration nuclear heating plant, which provides industrial steam for the chemical industrial park to satisfy the steam demand of enterprises. Meanwhile, the remaining capacity can be used for power generation, so as to alleviate the local power shortage. As the condensed water of the externally supplied steam is not recovered, and the freshwater source is insufficient, it is necessary to build a seawater desalination plant and a demineralized water production plant to provide a large amount of demineralized water for the heating system. According to the raw seawater quality, requirements of produced water quality and technical & economic analysis, the main treatment process flow of seawater desalination system is: air flotation tank → horizontal mechanical filter → ultrafiltration membrane → seawater reverse osmosis membrane → freshwater reverse osmosis membrane. The main treatment process flow of demineralized water production system is: cation exchanger → anion exchanger → mixed ion exchanger. Combined with the engineering practice, this paper expounds the process system design of large-scale seawater desalination and demineralized water production from the aspects of seawater desalination process comparison and selection, reverse osmosis membrane seawater desalination process system design and process equipment configuration, etc. The system improves the guarantee rate of desalinated seawater and demineralized water supply, and realizes the emission reduction of industrial wastewater, which can provide reference for the process design of large-scale seawater desalination and demineralized water production in subsequent nuclear heating projects or nuclear power projects.
Research and Reflection on a Systematic and Integrated Application of Human Factors Engineering in Nuclear Power Plant
Authors: Xu Zhihui , Zhang Yuxin , Peng Huaqing , Yang Ming 
Published: November 2022

Abstract
Human factors engineering focuses on human-machine-environment coordination. The purpose is to prevent and reduce human errors in complex human-machine system, and improve the reliability of human-machine system. Based on the latest engineering practice of British generic design assessment for “HPR1000”, this paper introduces a systematic human factor analysis and argument technology by an integration of human factors engineering elements, as well as its engineering application. The engineering practice showed that this systematic method that integrates multiple elements of human factors engineering, can fully combine with the design characteristics of nuclear power plant, comprehensively analyze and consider the impact of human factors on nuclear power plant design, and can transmit and iterate risk information among various professional fields s. It is an effective way to realize the in-depth application of human factors engineering.
Experimental Study on the Feasibility of Dry Grinding of MOX Core Blocks
Authors: Mao Jianzhong , Liu Xin , Wang Ben , Zhang Pengfei , Gao Bo 
Published: November 2022

Abstract
The MOX core block is the main component of the MOX fuel assembly. In this paper, a resin-bonded diamond cup wheel was used for grinding experiments on three ceramic materials, ZrO2, CeO2+AL2O3 and CeO2+MgO, with similar properties to the MOX core block. A grinding temperature prediction model was established using the circular contact moving heat source model, and the grinding temperature of the workpiece surface was predicted and the control strategy was studied in conjunction with the grinding experimental results to evaluate the dry grinding adaptability of the MOX core block based on the workpiece surface grinding temperature. The results show that when the grinding wheel linear speed Vs = 60 m/s, the workpiece feed linear speed Vwt = 627mm/s, and the grinding depth is in the range of 0.01mm∼0.04mm single side grinding depth, the grinding temperature of the workpiece surface is below 200°C, and the oxidation temperature of the workpiece is not reached, therefore, the dry grinding method is considered suitable for the machining of MOX core blocks.
Preliminary Design on the Wide Dynamic and Fast Response Electronic System for the 4H-SiC PIN Fast Neutron Detector
Authors: Yong Ma , Shuhuan Liu , Shuangying Liu 
Published: November 2022

Abstract
Based on the measured dynamic range of fast neutron injection rate, 4H-SiC PIN detector fast neutron detection efficiency and detector output current signal distribution characteristics, this paper designs and develops a current sensitive front-end readout circuit based on a high bandwidth transimpedance amplifier (ADI LTC6268-10), analyzes the main factors affecting the front-end circuit characteristics, and explores the main methods to improve the linear range of the front-end circuit. The main methods to improve the linear range of the front-end circuit are explored. Second, according to the front-end circuit output signal characteristics, based on high-bandwidth ADC (AD9680) and Zynq UltraScale+ MPSoC XCZU15EG development board, a digital data acquisition system (DAQ) was designed and developed. The preliminary simulation and experimental test results show that the designed detector electronics circuit has a good linear response under the conditions of input current pulse frequency of 20MHz, peak value of 10μA∼100μA and pulse width of 5ns. The research results provide relevant technical support for the establishment of 4H-SiC detector electronics system.
Development and Verification of Heat Pipe and Fin Radiation Heat Dissipation Program Based on MOOSE Platform
Authors: Wang Sipeng , Chen Xiaoquan , Tian Rui 
Published: November 2022

Abstract
Nuclear energy is an integral part of the energy supply required for future space exploration as efficient energy. Although heat pipe reactor is the main development direction of space reactor. Radiation radiator quality accounts for a large proportion of heat pipe reactor quality. Therefore, it is essential to improve the heat dissipation performance of the heat pipe reactor, effectively reducing the quality of the radiator under the condition of ensuring that the radiation heat dissipation power of the radiator is not less than that of the same volume radiator, design the optimal heat pipe cooling scheme and promote the development of space heat pipe reactor. In this paper, based on the finite element multi-physical coupling MOOSE platform, a program is developed to simulate the physical field of the heat pipe reactor radiator. The simulation of the heat pipe, fin and other parts of the radiator end unit is realized, and the combination of heat pipe and fin calculation is completed. At the same time, the temperature field of the new heat pipe radiator unit is obtained. The simulation results for the heat pipe and fin module are verified by the temperature field calculation program and another multi-physical coupling software. Another multi-physical coupling software results are compared with MOOSE simulation results for the combination part. The results show that the MOOSE program can reasonably simulate the heat transfer state in the simulation of heat pipes, fins, and combinations. The temperature field agrees with the verification results.
Model Evaluation of Various Thermo-Physical Properties of Nanofluids and ANN Modelling for 10kWe Integrated Reactor
Authors: Zheng Ling-Yun , Zhang Zhi-Gang , Wang Xin-Wen 
Published: November 2022

Abstract
A 10kWe integrated reactor with Stirling generator is in design, to satisfy China’s power demand for both Earth orbit and deep space exploration in the next two decades. The integration of the core and the thermoelectric conversion system, reduces the number of tubes and pump structures, which leads to a higher energy conversion rate, fewer failure risks and coolant leaks. The waste heat of this reactor would be transferred through its heat pipes to its radiators, then to the space. Applying nanofluids would help reduce the heat pipe sizes, because nanofluids have great alterations in their thermo-physical properties with a small fraction of nanoparticles. Numerous models have been proposed to characterize the thermo-physical properties of nanofluids. However, it is found that researchers have different, sometimes even contradictory conclusions about some of the properties. At the same time, these properties could be affected by various aspects, the simple models are not sufficient for the reference. This work focuses on evaluating the models of density, specific heat capacity, thermal conductivity, viscosity, and Nusselt number of nanofluids with statistical methods, and provides reference thermo-physical properties for the design of the heat pipes in the space reactor. For this reason, a great amount of experimental data is collected. Profiting from the collected data, artificial neural network (ANN) models based on Pytorch are trained and compared with the other models.
Research on LOCA Dynamic Analysis Model of Reactor System
Authors: Liu Shuai 
Published: November 2022

Abstract
The reactor system has a large scale of components. And the system dynamic analysis model for loss of coolant accidents (LOCA) contains many non-linear factors. The transient calculation analysis takes a long time and the convergence is difficult to guarantee. In this paper, two different analysis models (complete three-loop model and single-loop model) of the reactor loop system are established for comparative analysis. The analysis shows that the calculation error of the main position load in the two different model is within 10%. The decoupling influence of the surge tube and the reactor inlet and outlet on the system dynamic characteristics is within an acceptable range. When the single-loop model is used, it is necessary to decouple the reactor pressure vessel and pressurizer. And the simplified boundary is adapted to simulate its effect on the whole loop. The single-loop dynamic analysis model based on the decoupling criterion can greatly reduce the calculation scale and meet the calculation accuracy, which can be used to calculate the LOCA dynamic characteristics of the reactor system quickly. The model can also be used for seismic analysis of reactor system. And using this model for reactor system dynamic analysis can greatly improve the calculation efficiency.
Research on the Practice Qualification System of Registered Nuclear Safety Engineer From the Perspective of Access Professional Qualification
Authors: Chen Fangqiang , Zhang Yang , Jia Wei , Li Zhaotong , Wang Guanyi 
Published: November 2022

Abstract
In order to improve the professional and technical level of China’s nuclear and radiation safety practitioners, enhance their safety literacy, China established Registered Nuclear Safety Engineer Qualification License System (hereinafter referred to as RNSES). Registered nuclear safety engineers not only need to master the knowledge of nuclear safety professional technology, but also need to master the knowledge of nuclear safety laws and regulations, department rules, nuclear safety guidelines, relevant national standards and industry standards, nuclear safety culture, etc. RNSES has good advantages and positive support for the implementation of nuclear safety regulations and national standards in the nuclear field. Nevertheless, the system has been established for 20 years and has accumulated some problems to be solved. Now, RNSES is planned to be adjusted. From the perspective of professional qualification of admittance, the paper makes a multi-dimensional statistical study on the construction of other professional qualification access systems, intuitively points out the realities and shortcomings of the registered nuclear safety engineer system, and then puts forward specific suggestions to strengthen the construction of the access system of certified nuclear safety engineers, so as to provide policy reference for the system reform.
Pulverization and Spheroidization of Natural Graphite Powder for The Matrix Graphite in High-Temperature Gas-Cooled Reactors
Authors: Cao Xinlei , Lu Zhenming , Feng Yuxiao , Bai Juan , Liu Bing , Shen Ke 
Published: November 2022

Abstract
Matrix graphite (MG) constitutes a major component of the fuel element in high-temperature gas-cooled reactors (HTRs), and its performance directly affects the economy and safety of HTRs. A3-3 MG, developed in Germany in the last century, is still used today without significant changes. However, with the successful commercialization of HTR, there is an urgent need to develop MG that is suitable for the characteristics of each country. In this paper, comparative studies on the powder processing of natural flake graphite were carried out based on the raw materials from Inner Mongolia. First, the influence of the sequence of purification and pulverization on the basic properties of graphite powder was studied. Second, the influence of the degree of spheroidization of the natural flake graphite powder on the properties of the MG was further investigated, and the controlling mechanism of the spheroidization process on the microstructure and physical properties of the MG was revealed. The results of this study provide important insights for optimizing the preparation process of HTR fuel element MG.
Research on Laser Welding Process and Deformation Control of Irradiated Sample Holder
Authors: Luo Shouyi , Guo Baochao , Mi Dawei 
Published: November 2022

Abstract
In order to study the influence of laser welding parameters on the weld formation and the deformation of the irradiated sample holder, laser lap welding tests were carried out on 304 stainless steel sheets with the thicknesses of 8.97mm and 20mm. Firstly, orthogonal tests were carried out to study the effect of welding speed and defocus on weld morphologies. The results showed that when the laser power was 10kW, the welding speed was 15mm/min, and the defocus amount was −1mm, the optimized weld with the aspect ratio of 2.13 can be obtained. Next, a novel fixture designed for the welding of the irradiated sample holder was introduced, which effectively reduced the deformation of workpieces during the welding process. Additionally, in order to compensate the deformation induced by the weld shrinkage and residual stress, a filler gauge of 0.75mm height was used to create an inverse deformation. it was proved that the welding deformation could be effectively controlled after the preforming, and the deformation could be controlled below 0.7mm. Finally, the influence of welding sequence on the deformation of the irradiated sample holder under the optimized welding parameters was investigated. It was shown that the optimal welding sequence of the irradiated sample holder was: firstly the arc positioning welding, then the laser positioning welding, and finally the laser deep penetration welding. The welding deformation can be effectively controlled by adding the fixture and adjusting the welding sequence, the change of flatness before and after the laser deep penetration welding could reach 1.09mm.