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Remaining useful life prediction of aircraft lithium-ion batteries based on F-distribution particle filter and kernel smoothing algorithm

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Chinese Journal of Aeronautics 2020年第5期33卷 1517-1531页

作者： Kai ZHANG Peng ZHAO Canfei SUN Youren WANG Zewang CHEN college of automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China aviation Industry Corporation Leihua Electronic Technology Research Institute Wuxi 214000China Testing and Verification Center Aviation Key Laboratory of Science and Technology on Fault Diagnosis and Health ManagementShanghai 201601China

As an emergency and auxiliary power source for aircraft,lithium(Li)-ion batteries are important components of aerospace power *** Remaining Useful Life(RUL)prediction of Li-ion batteries is a key technology to ensure the reliable operation of aviation power *** Filter(PF)is an effective method to predict the RUL of Li-ion batteries because of its uncertainty representation and management ***,there are problems that particle weights cannot be updated in the prediction stage and particles *** settle these issues,an innovative technique of F-distribution PF and Kernel Smoothing(FPFKS)algorithm is *** the prediction stage,the weights of the particles are dynamically updated by the F kernel instead of being fixed all the ***,a first-order independent Markov capacity degradation model is ***,the kernel smoothing algorithm is integrated into PF,so that the variance of the parameters of capacity degradation model keeps *** based on NASA battery data sets show that FPFKS can be excellently applied to RUL prediction of Liion batteries.

关键词： F-distribution Kernel smoothing Lithium-ion batteries Markov model Particle filter Prediction Remaining useful life

Numerical computation and analysis of high-speed autonomous underwater vehicle (AUV) moving in head sea based on dynamic mesh

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Journal of Central South university 2012年第11期19卷 3084-3093页

作者：高富东潘存云徐小军韩艳艳 college of Mechatronic Engineering and automation National University of Defense Technology Department of Shipboard aviation Security and Station Management Naval Aeronautical and Astronautical University SANY Heavy Industry Co.Ltd.

Autonomous underwater vehicles （AUVs） navigating on the sea surface are usually required to complete the communication tasks in complex sea conditions. The movement forms and flow field characteristics of a multi-moving state AUV navigating in head sea at high speed were studied. The mathematical model on longitudinal motion of the high-speed AUV in head sea was established with considering the hydrodynamic lift based on strip theory, which was solved to get the heave and pitch of the AUV by Gaussian elimination method. Based on this, computational fluid dynamics （CFD） method was used to establish the mathematical model of the unsteady viscous flow around the AUV with considering free surface effort by using the Reynolds-averaged Navier-Stokes （RANS） equations, shear-stress transport （SST） k-w model and volume of fluid （VOF） model. The three-dimensional numerical wave in the computational field was realized through defining the unsteady inlet boundary condition. The motion forms of the AUV navigating in head sea at high speed were carried out by the program source code of user-defined function （UDF） based on dynamic mesh. The hydrodynamic parameters of the AUV such as drag, lift, pitch torque, velocity, pressure and wave profile were got, which reflect well the real ambient flow field of the AUV navigating in head sea at high speed. The computational wave profile agrees well with the experimental phenomenon of a wave-piercing surface vehicle. The force law of the AUV under the impacts of waves was analyzed qualitatively and quantitatively, which provides an effective theoretical guidance and technical support for the dynamics research and shape design of the AUV in real complex environnaent.

关键词： computational fluid dynamics dynamic mesh autonomous underwater vehicle (AUV) motion head sea viscous flowfield

Investigation on influence of alloying on phase transitions of duplex stainless steel based on thermochemical calculation

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china Welding 2023年第4期32卷 11-28页

作者：张志强刘博徐连勇韩永典赵雷曲思成 college of aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore School of Materials Science and Engineering Tianjin UniversityTianjin 300072China

This paper investigated on influence of different alloying elements added into duplex stainless steel (DSS) on phase transitions using thermochemical methods in comparison with *** results showed that the most possible species in the ferrite phase,austenite phase,σphase,Hcp phase,χphase,and carbide were Cr:Va-type,Fe:Va-type,Ni:Cr:Mo-type,Cr_(2)N-type,Fe_(24)Mo_(10)Cr_(24)-type,and Cr:Mo:C-type,***,the Ni,N,Cr,and Mo alloying had significant influences on the transition of each DSS *** Ni and N additions obviously raised the temperature at ferrite-1/austenite-1 balance while the Cr and Mo decreased the dual-phase balance *** addition,the Ni addition can promote the precipitating ofσphase at relatively high temperature while the precipitating of Hcp phase at relatively low *** Hcp phase andχphase can be obviously increased by the N *** introduction of Cr and Mo notably enhances the precipitation ofσ***,the promotion ofχphase precipitation is facilitated by the presence of Mo,while the Cr element acts as an inhibitor forχphase ***,the ferrite/austenite ratio tested by experiment was higher than that calculated by thermochemical methods,thus pre-designed solution temperature should be lower about 30-100℃than that calculated by thermochemical methods.

关键词： phase transitions precipitation alloying thermochemistry duplex stainless steel

Research on the Evaluation Method of Aircraft Virtual Maintenance Training Based on AHP

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Research on the Evaluation Method of Aircraft Virtual Mainte...

2012年计算机应用与系统建模国际会议

作者： Song Yunxue Li Zongbo college of aeronautical Engineering civil aviation university of china

In this paper, AHP is applied to the evaluation of student maintenance capability in virtual maintenance environment, and the design of evaluation system is achieved. Firstly, the mathematical model of AHP is introduced. And then, according to the index system of maintenance training in aircraft maintenance organizations and the characteristics of the virtual maintenance environment, evaluation index system is given. And evaluation model is created. At last, the design of evaluation system is given. The function of each system module is introduced briefly and the process of the system is given. The evaluation system uses the AHP, the quantitative analysis and qualitative analysis, which can reduce the influence of human factors, to enhance the objective and scientific of decision.

关键词： AHP Virtual Maintenance Evaluation System

Application of DELMIA on Maintainability Design of Aircraft

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Application of DELMIA on Maintainability Design of Aircraft

2012年计算机应用与系统建模国际会议

作者： Shi Yongsheng Liu Yu college of aeronautical Engineering civil aviation university of china

The quality of the maintainability is the key to success of modern large aircraft, In this paper, the flow of interactive maintenance design (Design For Maintenance, DFM) is introduced based on the DELMIA software, Also the requirements of maintainability design. We established the models of Boeing 737-300 aircraft nose gear, and maintenance process of the gear is simulated. We also explored how to find and overcome the maintenance trouble in the design and maintenance aspects. From the perspective of accessibility and operability, maintainability analysis of landing gear maintenance is completed. Proof of using the DELMIA software, may realize the aircraft ’DFM’ optimization.

关键词： DELMIA Design For Maintenance maintainability Maintenance Trouble

A Numerical Research on Diverse Cratered Film Cooling Hole Geometries

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A Numerical Research on Diverse Cratered Film Cooling Hole G...

高等教育学会工程热物理专业委员会第二十一届全国学术会议

作者： Weijia Qian Zongwei Zhang college of aeronautical Engineering Civil Aviation University of China

The goal of this research is to investigate cratered hole geometries on film cooling *** kinds of cratered holes,namely,the concentric crater,the circular crater,the downstream offset crater,the upstream offset crater,and the direct crater are being studied along with the conventional flush *** craters has the same depth of 0.5 hole *** numerical simulation with CFX at a single blowing ratio of 0.5 and Reynold number of 11000,we analyze and compare the performance and behavior of five kinds of cratered holes with the conventional cylindrical *** simulation employs k-εturbulent model and wall *** cooling effectiveness is achieved for all *** all cases,concentric cratered hole perform the best which increases averaged film cooling effectiveness by 64%at X/D=*** cratered holes appear some performance improvement compared to the baseline *** cratered holes,film lateral convergence and stream-wise attaching performance was both enhanced owing to the expansional configuration of the crater and the consequent backflow region.

关键词： cratered hole film cooling cooling effectiveness turbine blade numerical simulation

Comparison on Vulnerability of European and Chinese Air Transport Networks under Spatial Hazards

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Transactions of Nanjing university of Aeronautics and Astronautics 2020年第2期37卷 300-310页

作者： LI Hang LIU Xinying ZHANG Yingfei HU Xiaobing china France Research Center of Applied Mathematics for ATM Civil Aviation University of ChinaTianjin 300300P.R.China college of Electronic Information and automation Civil Aviation University of ChinaTianjin 300300P.R.China college of the Flight Technology Civil Aviation University of ChinaTianjin 300300P.R.China college of Economics and Management Civil Aviation University of ChinaTianjin 300300P.R.China

European air transport network(EATN)and Chinese air transport network(CATN),as two important air transport systems in the world,are facing increasingly spatial hazards,such as extreme weathers and natural disasters. In order to reflect and compare impact of spatial hazards on the two networks in a practical way,a new spatial vulnerability model(SVM)is proposed in this paper,which analyzes vulnerability of a network system under spatial hazards from the perspectives of network topology and characteristics of hazards. Before introduction of the SVM,two abstract networks for EATN and CATN are established with a simple topological analysis by traditional vulnerability method. Then,the process to study vulnerability of an air transport network under spatial hazards by SVM is presented. Based on it,a comparative case study on EATN and CATN under two representative spatial hazard scenarios,one with an even spatial distribution,named as spatially uniform hazard,and the other with an uneven spatial distribution that takes rainstorm hazard as an example,is conducted. The simulation results show that both of EATN and CATN are robust to spatially uniform hazard,but vulnerable to rainstorm hazard. In the comparison of the results of the two networks that only stands from the points of network topology and characteristics of hazard without considering certain unequal factors,including airspace openness and flight safety importance in Europe and china,EATN is more vulnerable than CATN under rainstorm hazard. This suggests that when the two networks grow to a similar developed level in future,EATN needs to pay more attention to the impact of rainstorm hazard.

关键词： vulnerability spatial vulnerability model(SVM) air transport networks spatial hazards

基于威布尔分布的民机隐性功能系统维修间隔优化研究（英文）

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机床与液压 2016年第6期44卷 40-46页

作者： Yu- xin WANG Hang YANG Bao-hui JIA Yao-hua LI aeronautical Engineering college Civil Aviation University of China Tianjin 300300 China

This paper comes up with a cost rate function （CRF） aimed at the problem of hidden function systemmaintenance interval optimization of civil aircraft, and studs to propose the optimal preventive maintenance policymodel and solution in ＂Overhaul period＂ based on Weibull distribution, which finally achieves the best optimiza-tion objectives of the maintenance task intervals of hidden failures （non-safety effects） of civil aircraft system. Fi-nally, the paper delivers the practical research by the reliability data of filter indicator pops of hydraulic system onB737, and proves the effectiveness and applicability of the optimization model and solution.

关键词： Hidden function system, Cost rate function, Weibull distribution, Maintenance task interval, Hiddenfailures

Fault Propagation of Aircraft Avionics System Based on SDG

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Fault Propagation of Aircraft Avionics System Based on SDG

第32届中国控制与决策会议

作者： Xue Jiao Zhao Zhen college of Aerospace Engineering Civil Aviation University of China college of Electronic Information and automation Civil Aviation University of China

The problem of fault diagnosis and maintenance support for aircraft avionics systems has become increasingly *** complex relationship between various fault propagations during troubleshooting and the difficulty in locating and diagnosing faults by maintenance personnel are *** paper takes the avionics system of civil aircraft as the research object,adopts the method of signed directed graph to model the avionics system,and uses the form of matrix to represent the directed graph model to study the propagation of *** Dijkstra algorithm combines the stack-based depth-first traversal algorithm to analyze the fault propagation path to find all the propagation paths and the shortest propagation paths of the fault,and obtain the fault source most likely to be faulty,for subsequent fault diagnosis and system *** and maintenance provide theoretical support.

关键词： avionics system signed directed graph fault propagation fault diagnosis