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Dynamics response analysis of airborne external storage system with clearance between missile-frame

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Chinese Journal of Aeronautics 2020年第12期33卷 3278-3287页

作者： Yongfeng YANG Qingyang ZHENG Jianjun WANG Zhongfu MA Xiangqiu LIU Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Key Laboratory of Vibration and Control of Aero-propulsion system Ministry of Education Northeastern UniversityShenyang 110819China China Airborne missile Academy Luoyang 471099China

Considering the aircraft and its external components are subjected to complex and variable aerodynamic loads during the working process,the missile-frame clearance system of the airborne external missile is *** random vibration characteristics of the airborne external components are analyzed by finite element *** finite element model is optimized with reference to the test results,and the effects of different clearance on the dynamic response of the missile-frame system are *** result shows that the frequency response curves of the same position and the resonant peak frequencies are consistent under different *** acceleration response at both ends of the missile is large and the amplitude near the center of mass is *** results can be used to predict reasonable missile-frame clearance and make guidance to the structural design and reliability analysis of the missile-frame system.

关键词： Airborne Dynamic response Finite element method(FEM) missile-frame Random vibration

AN INTRODUCTION TO THE NASA EAST PACIFIC ORIGINS AND CHARACTERISTICS OF HURRICANES(EPOCH) FIELD CAMPAIGN

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Tropical Cyclone Research and Review 2015年第3期4卷 124-131页

作者： AMBER E.EMORY MATTHEW MCLINDEN MATHIAS SCHREIER GARY A.WICK NASA Goddard Space Flight center GreenbeltU.S.A. Jet propulsion Laboratory PasadenaU.S.A. NOAA Earth system Research Laboratory BoulderU.S.A.

Over the past fi ve years, tropical activity in the East Pacifi c has increased, while declining in the Atlantic Basin. In addition, during El Ni?o years, warmer than average sea surface temperatures further increase the likelihood of tropical cyclone formation in the East Pacifi c. Hurricane fi eld campaigns used the Ku-/Ka-band HighAltitude Wind and Rain Airborne Profi ler(HIWRAP) radar on the Global Hawk(GH) unmanned aircraft, in GRIP(Genesis and Rapid Intensifi cation Processes 2010), HS3(Hurricane and Severe Storm Sentinel 2012-14), and the NOAA Sensing Hazards with Operational Unmanned Technology(SHOUT 2015-16) fi eld campaigns. Although originally designed for the GH, the X-band high-altitude RADar(EXRAD) has yet to be integrated and fl own on an unmanned aerial vehicle. EXRAD will provide data with less attenuation of signal over deep convection as well as better estimates of three-dimensional winds with its nadir-pointing beam. As part of the NASA Hand On Project Experience(HOPE) Training Opportunity, our team proposed to fl y the AV-6 GH aircraft with the EXRAD radar, the High Altitude MMIC Sounding Radiometer(HAMSR), and NOAA Advanced Vertical Atmospheric Profi ling system(AVAPS) dropsondes to investigate genesis and/or rapid intensifi cation(RI) of an East Pacifi c hurricane by measuring both the environment and interior structures. Information on planned activities primarily focused on the EXRAD high-altitude radar integration for the July-August 2017 science fl ight will be presented.

关键词： GH FIELD CAMPAIGN AN INTRODUCTION TO THE NASA EAST PACIFIC ORIGINS AND CHARACTERISTICS OF HURRICANES EPOCH

Study on High Power Hall Electric propulsion Technology

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Aerospace China 2020年第2期21卷 31-38页

作者： HANG Guanrong ZHAO Zhen YU Shuilin QIAO Caixia LIU Jia HUANG Hao TIAN Leichao LI Lin LI Wenshuai KANG Xiaolu Shanghai Institute of Space propulsion Shanghai 201112 Shanghai Engineering Research center of Space Engine Shanghai 201112

High power Hall electric propulsion technology is a very competitive electric propulsion technology for future large space missions such as large GEO satellites,manned space programs,deep space explorations,cargo ships,space *** on the experience of more than 20 years in research and development of Hall electric propulsion,the Shanghai Institute of Space propulsion(SISP)has developed 3 high power Hall thrusters,i.e.,the 10 k W class HET-500,20 k W class HET-1000,and 50 k W class *** paper presents the development status of the high power(≥10 k W)Hall electric propulsion at SISP,including tests of 3 high power Hall thrusters in the power range from 10 k W to 50 k W,the qualification of a single string of a 10 k W Hall electric propulsion system,and the study of a cluster of two 1.35 k W HET-80 Hall thrusters to understand the technical issues related to multi-thruster high power electric propulsion systems.

关键词： high power Hall electric propulsion Hall thruster single string system integration thruster cluster

Modeling and Decentralized Predictive Control of Ejector Circulation‑Based PEM Fuel Cell Anode system for Vehicular Application

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Automotive Innovation 2022年第3期5卷 333-345页

作者： Bo Zhang Dong Hao Jinrui Chen Caizhi Zhang Bin Chen Zhongbao Wei Yaxiong Wang College of Mechanical and Vehicle Engineering The State Key Laboratory of Mechanical TransmissionsChongqing Automotive Collaborative Innovation CentreChongqing UniversityChongqing 400044China China Automotive Technology&Research center Co. Ltd.Tianjin 300300China propulsion Research Institute of Chongqing Changan New Energy Vehicle Technology Co. LtdChongqing 400000China China Merchants Testing Certification Vehicle Technology Research Institute Co. Ltd.Chongqing 401329China National Engineering Laboratory for Electric Vehicles School of Mechanical EngineeringBeijing Institute of TechnologyBeijingChina School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

The dynamic response of fuel cell vehicle is greatly affected by the pressure of ***,the pressure difference between anode and cathode will also cause mechanical damage to proton exchange *** maintaining the relative stability of anode pressure,this study proposes a decentralized model predictive controller(DMPC)to control the anodic supply system composed of a feeding and returning ejector *** the important influence of load current on the system,the piecewise linearization approach and state space with current-induced disturbance compensation are com-paratively ***,an innovative switching strategy is proposed to prevent frequent switching of the sub-model-based controllers and to ensure the most appropriate predictive model is ***,simulation results demonstrate the better stability and robustness of the proposed control schemes compared with the traditional proportion integration differentia-tion controller under the step load current,variable target and purge disturbance *** particular,in the case of the DC bus load current of a fuel cell hybrid vehicle,the DMPC controller with current-induced disturbance compensation has better stability and target tracking performance with an average error of 0.15 kPa and root mean square error of 1.07 kPa.

关键词： Proton exchange membrane fuel cell Hydrogen ejector system disturbance Decentralized model predictive control Hydrogen pressure control

Streamwise-body-force-model for rapid simulation combining internal and external flow fields

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Chinese Journal of Aeronautics 2016年第5期29卷 1205-1212页

作者： Cui Rong Li Qiushi Pan Tianyu Zhang Jian National Key Laboratory on Aero-Engines Beihang University Collaborative Innovation center of Advanced Aero-Engine Beihang University Department of Engine Project Aviation Industry Corporation of China

A streamwise-body-force-model （SBFM） is developed and applied in the overall flow simulation for the distributed propulsion system, combining internal and external flow fields. In view of axial stage effects, fan or compressor effects could be simplified as body forces along the streamline. These body forces which are functions of local parameters could be added as source terms in Navier-Stokes equations to replace solid boundary conditions of blades and hubs. The val- idation of SBFM with uniform inlet and distortion inlet of compressors shows that pressure performance characteristics agree well with experimental data. A three-dimensional simulation of the integration configuration, via a blended wing body aircraft with a distributed propulsion system using the SBFM, has been completed. Lift coefficient and drag coefficient agree well with wind tunnel test results. Results show that to reach the goal of rapid integrated simulation combining internal and external flow fields, the computational fluid dynamics method based on SBFM is reasonable.

关键词： Aircraft Blended wing body Boundary layer ingestion Distributed propulsion sys-tem Integrated simulations Streamwise-body-force-model

Effects of Lobe Peak-to-Trough Width Ratio on Mixing and Combustion Performance in ATR Combustors

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Transactions of Nanjing University of Aeronautics and Astronautics 2022年第6期39卷 637-650页

作者： ZHAO Qingjun ZHANG Yuankun HU Bin WANG Zhonghao SHI Qiang ZHAO Wei Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190P.R.China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100190P.R.China Innovation Academy for Light-Duty Gas Turbine Chinese Academy of SciencesBeijing 100190P.R.China Beijing Key Laboratory of Distributed Combined Cooling Heating and Power system Chinese Academy of SciencesBeijing 100190P.R.China

The air-turbo-rocket(ATR)engine is a promising propulsion plant for achieving numerous surface and air launched missile *** application of lobed mixer in the ATR combustor can promote the mixing of the fuelrich gas and the air,thus improving the engine performance *** numerical simulation method was conducted to explore the effects of lobe peak-to-trough width ratio on mixing and combustion performance in ATR *** show that:For a given peak lobe width b1,the combustion efficiency and total pressure loss decrease with the increase of trough lobe width b2;For a given b2,the combustion efficiency and total pressure loss decrease with the increase of b1;The fan-type lobed mixer with smaller b2has a better effect on promoting the combustion efficiency in the region near the ATR combustor center line than that with a pair of parallel side *** total pressure recovery coefficient reaches more than 0.99 at the exit of combustor in nonreactive combustion while the total pressure loss reaches more than 4%in the reacting *** with the mixing process,more than80%of the total pressure loss is caused during combustion.

关键词： ATR combustor lobed mixer lobe peak-to-trough width ratio mixing combustion streamwise vortex

Critical review and functional safety of a battery management system for large‑scale lithium‑ion battery pack technologies

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International Journal of Coal Science & Technology 2022年第3期9卷 1-17页

作者： K.W.See Guofa Wang Yong Zhang Yunpeng Wang Lingyu Meng Xinyu Gu Neng Zhang K.C.Lim L.Zhao Bin Xie Azure Mining Technology CCTEG 821 Pacifc HighwaySydneyNSW 2067Australia China Coal Research Institute Beijing 100013China China Mining Products Safety Approval and Certifcation center Beijing 100013China School of Mechanical Electronic and Information Engineering China University of Mining and TechnologyBeijing 100083China Beijing Tianma Intelligent Control Technology Co. LtdBeijing 101399China Australian Institute for Innovative Materials Institute for Superconducting and Electronic MaterialsUniversity of WollongongInnovation CampusWollongongNSW 2500Australia

The battery management system(BMS)is the main safeguard of a battery system for electric propulsion and machine *** is tasked to ensure reliable and safe operation of battery cells connected to provide high currents at high voltage *** addition to efectively monitoring all the electrical parameters of a battery pack system,such as the voltage,current,and temperature,the BMS is also used to improve the battery performance with proper safety measures within the *** growing acceptance of lithium-ion batteries,major industry sectors such as the automotive,renewable energy,manufacturing,construction,and even some in the mining industry have brought forward the mass transition from fossil fuel dependency to electric powered machinery and redefned the world of energy ***,the functional safety considerations,which are those relating to automatic protection,in battery management for battery pack technologies are particularly important to ensure that the overall electrical system,regardless of whether it is for electric transportation or stationary energy storage,is in accordance with high standards of safety,reliability,and *** the system or product fails to meet functional and other safety requirements on account of faulty design or a sequence of failure events,then the environment,people,and property could be *** paper analyzed the details of BMS for electric transportation and large-scale energy storage systems,particularly in areas concerned with hazardous *** analysis covers the aspect of functional safety that applies to BMS and is in accordance with the relevant industrial standards.A comprehensive evaluation of the components,architecture,risk reduction techniques,and failure mode analysis applicable to BMS operation was also *** article further provided recommendations on safety design and performance optimization in relation to the overall BMS integration.

关键词： Battery management system Functional safety Hazardous area Lithium-ion batteries Failure mode analysis Electric transportation Large-scale energy storage