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Thermodynamic cycle analysis of solid propellant air-turbo-rocket

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航空动力学报 2009年第2期24卷 269-276页

作者： CHEN Xiang CHEN Yu-chun TU Qiu-ye ZHANG Hong CAI Yuan-hu School of power and Energy Northwestern Polytechnical University Xi'an 710072 China

Solid propellant air-turbo-rocket(SPATR) is an air-breathing propulsion system.A numerical model of performance and characteristics analysis for SPATR was presented and the corresponding computer program was written according to the operation characteristics of *** influence on the SPATR performance at design point caused by the gas generator exit parameters and compressor pressure ratio had been computed and analyzed in *** off-design performance of SPATR at sea level and high altitude had also been *** performance of thrust and specific impulse for SPATR with different solid propellant had been compared at off-design points,and the off-design performance comparison had been made between fuel-rich and *** computation results indicated that SPATR operates within wide range of Mach number(0~3) and altitude(0~12 km),and SPATR possesses high specific thrust(1 200 N/(kg/s)) and high specific impulse(7 000 N/(kg/s)) when fuel-air ratio of combustor equals fuel-air ratio.

关键词：空气涡轮火箭压缩机压力固体推进剂设计方案

Determination of the Minimum Wave Speed for the Modelling of Ventilated Cavitation

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Chinese Physics Letters 2016年第11期33卷 78-81页

作者：陈婷张宇宁杜小泽 Key Laboratory of Condition Monitoring and Control for power Plant Equipment(Ministry of Education) North China Electric Power University

Ventilated cavitation plays an important role on the drag reduction of underwater vehicles and surface ships. For the modelling of ventilated cavitation, the minimum speed of the pressure wave is a crucial parameter for the closure of the pressure-density coupling relationship. In this study, the minimum wave speed is determined based on a theoretical model coupling the wave equation and the bubble interface motion equation. The influences of several paramount parameters （e.g., frequency, bubble radius and void fraction） on the minimum wave speed are quantitatively demonstrated and discussed. Compared with the minimum wave speed in the traditional cavitation, values for the ventilated cavitation are much higher. The physical mechanisms for the above difference are briefly discussed with the suggestions on the usage of the present findings.

关键词： of is for Determination of the Minimum Wave Speed for the Modelling of Ventilated Cavitation in

Multi-objectives nonlinear structure optimization for actuator in trajectory correction fuze subject to high impact loadings

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Defence Technology（防务技术） 2021年第4期17卷 1338-1351页

作者： Jiang-hai Hui Min Gao Ming Li Ming-rui Li Hui-hui Zou Gang Zhou Northwest Institute of nuclear Technology Xi’an710025China Shijiazhuang Campus Army Engineering UniversityShijiazhuang050003China

This paper presents an actuator used for the trajectory correction fuze,which is subject to high impact loadings during launch.A simulation method is carried out to obtain the peak-peak stress value of each component,from which the ball bearings are possible failures according to the ***,three schemes against impact loadings,full-element deep groove ball bearing and integrated raceway,needle roller thrust bearing assembly,and gaskets are utilized for redesigning the actuator to effectively reduce the bearings’***,multi-objectives optimization still needs to be conducted for the gaskets to decrease the stress value further to the yield *** gasket’s structure parameters and three bearings’peak-peak stress are served as the four optimization variables and three objectives,*** Latin hypercube design is used for generating sample points,and Kriging model selected according to estimation result can establish the relationship between the variables and objectives,representing the simulation which is ***,two optimization algorithms work out the Pareto solutions,from which the best solutions are selected,and verified by the simulation to determine the gaskets optimized structure *** can be concluded that the simulation and optimization method based on these components is effective and efficient.

关键词： Actuator Trajectory correction fuze Impact loadings Optimized Latin hypercube design Kriging model Optimization algorithm

Viewpoint Optimization Method for Flying Robot Inspecting Transmission Towers Based on Point Cloud Model

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Chinese Journal of Electronics 2018年第5期27卷 976-984页

作者： LIU Chang'an DONG Ruifang JIN Lu WU Hua School of Control and Computer Engineering North China Electric Power University

This paper presents a method to derive optimal viewpoints for flying robot based transmission tower inspection, which applies point cloud model. A safe envelope is established according to safe transmission tower inspection rules. Essential inspection factors are proposed to evaluate the quality of candidate viewpoints, which includes visibility, dimensionality feature of point cloud as well as the distance between viewpoint and transmission power. A score function is constructed to quantify candidate viewpoints, while multiple attribute decision theory is applied to calculate the weight of each factor. Particle swarm optimization(PSO) is used to find the optimal viewpoints set. Both simulation experiment and practical observations are carried out. The results prove that optimal viewpoints have a great contribution for accurate transmission tower inspection. Final results are compared to patch-based method and proved to be feasible.

关键词： Transmission tower inspection Viewpoint optimization Point cloud model Particle swarm optimization(PSO) Flying robot

Collaborative Planning of Distributed Wind power Generation and Distribution Network with Large-scale Heat Pumps

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CSEE Journal of power and Energy Systems 2019年第3期5卷 335-347页

作者： Quansheng Cui Xiaomin Bai Weijie Dong china Electric power Research Institute Beijing 100192China

With the advancement of clean heating projects and the integration of large-scale distributed heat pumps into rural distribution networks in northern china,power grid companies face tremendous pressure to invest in power grid upgrades,which bring opportunities for renewable power generation *** combination of heating by distributed renewable energy with the flexible operation of heat pumps is a feasible alternative for dealing with grid reinforcement challenges resulting from heating *** this paper,a mathematical model of the collaborative planning of distributed wind power generation(DWPG)and distribution network with large-scale heat pumps is *** this model,the operational flexibility of the heat pump load is fully considered and the requirements of a comfortable indoor temperature are *** applying this model,the goals of not only increasing the profit of DWPG but also reducing the cost of the power grid upgrade can be achieved.

关键词： Collaborative planning distribution network distributed wind power generation large-scale distributed heat pumps

High-entropy(Sm_(0.2)Eu_(0.2)Gd_(0.2)Dy_(0.2)Er_(0.2))_(2)Hf_(2)O_(7) ceramic with superb resistance to radiation-induced amorphization

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Journal of Materials Science & Technology 2023年第24期155卷 1-9页

作者： Jingxin Wu Meng Zhang Zhanqiang Li Minzhong Huang Huiming Xiang Liyan Xue Zhengming Jiang Zhigang Zhao Lianfeng Wei Yong Zheng Fan Yang Guang Ran Yanchun Zhou Heng Chen School of Rare Earths University of Science and Technology of China Hefei 230026 China Ganjiang Innovation Academy Chinese Academy of Sciences Ganzhou 341000 China Xiamen Institute of Rare Earth Materials Haixi Institute Chinese Academy of Sciences Xiamen 361021 China Fujian Province Joint Innovation Key Laboratory of Fuel and Materials in Clean nuclear Energy System Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou 350002 China Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of china Fuzhou 350108 China Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials & Processing Technology Beijing 100076 China The Key nuclear Fuel and nuclear Materials Laboratory of china Nuclear Power Institute of China Chengdu 610213 China china Rare Earth Group Co. Ltd. Chengdu 610213 China College of Energy Xiamen University Xiamen 361102 China School of Materials Science and Engineering Zhengzhou University Zhengzhou 450001 China

nuclear engineering materials are required to possess outstanding extreme environmental tolerance and irradiation resistance.A promising novel pyrochlore-type of(Sm_(0.2)Eu_(0.2)Gd_(0.2)Dy_(0.2)Er_(0.2))2 Hf_(2)O_(7)high-entropy ceramic(HE-RE2 Hf_(2)O_(7))for control rod was prepared by solid-state reaction *** ion irradiation of HE-RE_(2) Hf_(2)O_(7)with 400 keV Kr+at 400℃was investigated using a 400 kV ion implanter and compared with single-component pyrochlore Gd2 Hf_(2)O_(7)to evaluate the irradiation *** HE-RE2 Hf_(2)O_(7),the phase transition from pyrochlore to defective fluorite is revealed after irradiation at 60 *** irradiation at 120 dpa,it maintained crystalline,which is comparable to Gd2 Hf_(2)O_(7)but superior to the titanate pyrochlores previously ***,the lattice expansion of HE-RE2 Hf_(2)O_(7)(_(0.2)2%)is much lower than that of Gd2 Hf_(2)O_(7)(0.62%),indicating excellent irradiation damage *** tests displayed an irradiation-induced increase in hardness and a decrease in elastic modulus by about 2.6%.Irradiation-induced segregation of elements is observed on the surface of irradiated *** addition,HE-RE2 Hf_(2)O_(7)demonstrates a more sluggish grain growth rate than Gd2 Hf_(2)O_(7)at 1200℃,suggesting better high-temperature *** linear thermal expansion coefficient of HE-RE2 Hf_(2)O_(7)is 10.7×10-6 K-1 at 298–1273 *** general,it provides a new strategy for the design of the next advanced nuclear engineering materials.

关键词： High-entropy ceramic Rare earth hafnate Ion irradiation Amorphization resistance High temperature stability nuclear safety

System Modeling and Optimal Dispatching of Multi-energy Microgrid with Energy Storage

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Journal of Modern power Systems and Clean Energy 2020年第5期8卷 809-819页

作者： Liting Tian Lin Cheng Jianbo Guo Kuihua Wu Department of Elec trical Engineering Tsinghua UniversityBeijingChina china Electric power Research Institute BeijingChina Economic&Technology Research Institute State Grid Shan dong Electric Power CompanyJinanShandongChina

The coordinated operation and comprehensive utilization of multi-energy sources require systematic research.A multi-energy microgrid(MEMG)is a coupling system with multiple inputs and *** this paper,a system model based on unified energy flows is proposed to describe the static relationship,and an analogue energy storage model is proposed to represent the time-dependency characteristics of energy transfer ***,the optimal dispatching model of an MEMG is established as a mixed-integer linear programming(MILP)problem using piecewise linear approximation and convex ***,the system model and optimal dispatching method are validated in an MEMG,including district electricity,natural gas and heat supply,and renewable *** proposed model and method provide an effective way for the energy flow analysis and optimization of MEMGs.

关键词： Energy flow energy storage multi-energy microgrid(MEMG) optimal dispatching

Development of a novel system for monitoring tritium in gaseous form

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nuclear Science and Techniques 2015年第2期26卷 67-70页

作者：陈志林彭述明陈华常瑞敏孟丹穆龙 Institute of nuclear Physics and Chemistry China Academy of Engineering Physics

Tritium real-time measurement in glovebox or workplace is important to ensure safe operation of tritium. A novel tritium monitor system including an open-walled ionization chamber, an electrometer and an IPC(Industrial Personal Computer) has been developed to measure tritium in gaseous form. Using mesh walls, instead of sealed wall, the open-walled ionization chamber has less tritium absorption and lower memory effect. In addition, tritium gas can diffuse into the chamber's sensitive region without the assistant of sampling system and ion trap, which are installed at the front-end of commonly used flow-through ionization chambers. Background signal of this monitor system is about 3.7 × 105Bq/m3, and after exposed to tritium concentration at about 1011Bq/m3 for 4h, background of the monitor can recover after purging it several times with dry air. It is suitable for longtime tritium measurements in both glovebox and workplace.

关键词：监控系统氚气气态开发工业个人计算机监测实时测量电离室

Modelling on thermal-fluid field in SF_(6)insulated high voltage direct current bushing with its influence on electric field distribution and metal particle motion

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High Voltage 2023年第2期8卷 380-389页

作者： Xiao Yang Yi Zhang Zhuodong Yang Hao Dong Chengrong Li Bo Qi Licheng Lu Caixin Sun State Key Laboratory of Alternate Electrical power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina Global Energy Interconnection Research Institute Co Ltd BeijingChina china Huaneng Group Co Ltd BeijingChina

The insulation performance of SF_(6)insulated high voltage direct current apparatus are often analysed in a pure electric field or electro-thermal coupled field while the fluid behaviour of SF_(6)gas flow is often ***,frequent flashover along the support insulators inside the SF_(6)insulated wall bushing indicates that the fluid characteristics of SF_(6)may have considerable influence on the interior insulation performance of the *** paper has simulated the thermo-fluid coupled field in the SF_(6)insulated wall bushing based on the finite element method *** result shows that buoyant flow of SF_(6)has evident influence on the temperature distribution in the *** this basis,the effect of the thermo-fluid field on the electric field distribution along the insulator as well as on the motion behaviour of the metallic particles is ***,the effect of different thermal boundary conditions on analysis of the multiphysics field in the bushing is discussed and the most suitable one for simulation and experiment is *** are made between different supporting structures and modification advices are *** paper can serve as a good reference for subsequent research studies on SF_(6)insulated apparatus in which the temperature gradient or the motion of the micro-sized metallic particles shall be considered.

关键词： distribution thermal field