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Microstructure, porosity and mechanical properties of selective laser melted AlSi10Mg

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Chinese Journal of aeronautics 2020年第7期33卷 2043-2054页

作者： Jing CHEN Wei HOU Xiuzhuan WANG Songlin CHU Zhiyi YANG Joint Laboratory of 3D Enable R&D Technology AECC Aero Engine Control System InstituteWuxi 214063China

Finite element modeling(FEM),microscopy,X-ray computed tomography(CT)and mechanical property tests were used to study the microstructure,porosity and mechanical properties of an AlSi10Mg alloy produced by selective laser melting(SLM).The simulation of the melt pool and thermal history under different energy densities produced an optimized result with an energy density of 44.5 J·*** high cooling rate during the SLM process significantly refined the previous a-Al *** growth direction of the network-like Al-Si eutectic structure at different orientations confirmed the anisotropic nature of the ***,the microhardness,tensile testing and fracture analysis results proved that there were no obvious distinctions in the strength between the transverse and longitudinal directions,and that the ductility was anisotropic,possibly due to the shape and distribution of the *** pores measured by X-ray CT at different energy densities confirmed that the sphericity of the pores was inversely related to pores *** optimized processing conditions,the porosity of the selective laser melted sample decreased leading to the improved fabricated fuel system component via SLM.

关键词： AlSi10Mg Mechanical property Microstructure Porosity Selective laser melting

A novel control method for turboshaft engine with variable rotor speed based on the Ngdot estimator through LQG/LTR and rotor predicted torque feedforward

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Chinese Journal of aeronautics 2020年第7期33卷 1867-1876页

作者： Yong WANG Qian’gang ZHENG Zhigui XU Haibo ZHANG College of Energy and Power engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China aecc aero engine control system institute Wuxi 214063China

In order to compensate for the disturbance of wide variation in rotor demanded torque on power turbine speed and realize the fast response control of turboshaft engine during variable rotor speed,a cascade PID control method based on the acceleration estimator of gas turbine speed(Ngdot)and rotor predicted torque feedforward is ***,a two-speed Dual Clutch Transmission(DCT)model is applied in the integrated rotor/turboshaft engine system to achieve variable rotor ***,an online estimation method of Ngdot based on the Linear Quadratic Gaussian with Loop Transfer Recovery(LQG/LTR)is proposed for power turbine speed cascade ***,according to the cascade PID controller based on Ngdot estimator,a rotor demanded torque predicted method based on the Min-batch Gradient Descent-Neural Network(MGD-NN)is put forward to compromise the influence of rotor torque *** simulation results show that compared with cascade PID controller based on Ngdot estimator and the one combined with collective pitch feedforward control,the novel control method proposed can reduce the overshoot of power turbine speed by more than 20%,which possesses faster response,superior dynamic effect and satisfactory robustness *** control method proposed can realize the fast response control of turboshaft engine with variable rotor speed better.

关键词： LQG/LTR Ngdot estimator Rotor predicted torque feedforward Turboshaft engine Variable rotor speed

Development of a deviation package method for low-cost robust optimization in compressor blade design

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Chinese Journal of aeronautics 2024年第4期37卷 166-180页

作者： Mingzhi LI Xianjun YU Dejun MENG Guangfeng AN Baojie LIU Research institute of aero-engine Beihang UniversityBeijing 100191China National Key Laboratory of Science&Technology on aero-engine aero-Thermodynamics Beihang UniversityBeijing 100191China aecc Shenyang engine Research institute Shenyang 110015China

Manufacture variations can greatly increase the performance variability of compressor blades. Current robust design optimization methods have a critical role in reducing the adverse impact of the variations, but can be affected by errors if the assumptions of the deviation models and distribution parameters are inaccurate. A new approach for robust design optimization without the employment of the deviation models is proposed. The deviation package method and the interval estimation method are exploited in this new approach. Simultaneously, a stratified strategy is used to reduce the computational cost and assure the optimization accuracy. The test case employed for this study is a typical transonic compressor blade profile, which resembles most of the manufacture features of modern compressor blades. A set of 96 newly manufactured blades was measured using a coordinate measurement machine to obtain the manufacture variations and produce a deviation package. The optimization results show that the scatter of the aerodynamic performance for the optimal robust design is 20% less than the baseline value. By comparing the optimization results obtained from the deviation package method with those obtained from widely-used methods employing the deviation model, the efficiency and accuracy of the deviation package method are demonstrated. Finally, the physical mechanisms that control the robustness of different designs were further investigated, and some statistical laws of robust design were extracted.

关键词： Manufacture variations Robust design optimization Compressor leading edge aerodynamics Physical mechanism

Numerical simulation research on multiphase flow of aviation centrifugal pump based on OpenFOAM

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Chinese Journal of aeronautics 2024年第4期37卷 256-275页

作者： Xianwei LIU Jiangfeng FU Junjie YANG Dewen YIN Zhenhua ZHOU Huacong LI College of Power and Energy Northwestern Polytechnical UniversityXi’an 710072China Norinco Group Testing and Research institute Huayin 714200China aecc Xi’an engine control Technology Co.Ltd. Xi’an 710077China aecc Guizhou Honglin aero engine control Technology Co.Ltd. Guiyang 550009China

This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation ***,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate ***,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is *** research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography *** on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately *** error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.

关键词： aero engine Fuel centrifugal pump Multiphase flow OpenFOAM Volume of fluid

An experimental method to obtain the hard alpha anomaly distribution for titanium alloy aeroengine disks

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Chinese Journal of aeronautics 2021年第4期34卷 67-82页

作者： Shuiting DING Huimin ZHOU Bochao PAN Haibin JI Xiaojun GUO Guo LI Aircraft/engine Integrated system Safety Beijing Key Laboratory School of Energy and Power EngineeringBeihang UniversityBeijing 100083China institute of Metal Research Chinese Academy of SciencesShenyang 110004China aero engine Corporation of China(aecc) Hunan Aviation Powerplant Research InstituteZhuzhou 412000China

A probability-based damage tolerance methodology has been proposed to improve the recognition of material anomalies, especially hard alpha(TiN) anomalies for aeroengine rotor disks. A key input to this method is hard alpha anomaly distribution, which reflects the occurrence rate and size of anomalies present in the finished part material of titanium rotors. Since anomalies rarely occur naturally, an experimental method is proposed to obtain the anomaly distribution for titanium alloy aeroengine disks to reflect and equivalently replace the manufacturing development in titanium industry. In general, the anomaly distribution information can be divided into two parts: the Probability of Detection(POD) curve and the detected anomaly distribution, which contains the size and frequency data of the detected anomalies. The distribution can be established based on several appropriate assumptions and derivation steps with different confidence levels of POD curves and detected anomaly distributions. In this case, the distribution can be obtained in a relatively short time as a key input to the probability-based damage tolerance methodology. Then the Probability of Failure(POF) can be calculated, and the value is found to vary with different confidence levels. On this basis, the conservative estimated POF can be obtained in conjunction with confidence levels.

关键词： aeroengine disk Artificial preparation Hard alpha anomaly distribution Probability of detection(POD) Probability risk assessment

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

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Frontiers of Mechanical engineering 2021年第4期16卷 798-813页

作者： Hexiang YUAN Jiapeng YU Duo JIA Qiang LIU Hui MA School of Mechanical engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and control of aero-Propulsion system(Ministry of Education) Northeastern UniversityShenyang 110819China Shenyang engine Research institute of aecc Shenyang 110015China School of Information and control engineering Liaoning Petrochemical UniversityFushun 113001China

External pipe routing for aero-engine in limited three-dimensional space is a typical nondetermini-stic polynomial hard problem,where the parallel layout of pipes plays an important role in improving the utilization of layout space,facilitating pipe assembly,and *** paper presents an automatic multiple pipe routing method for aero-engine that focuses on parallel *** compressed visibility graph construction algorithm is proposed first to determine rapidly the rough path and interference relationship of the pipes to be *** on these rough paths,the information of pipe grouping and sequencing are obtained according to the difference degree and interference degree,***,a coevolutionary improved differential evolution algorithm,which adopts the coevolutionary strategy,is used to solve multiple pipe layout optimization *** using this algorithm,pipes in the same group share the layout space information with one another,and the optimal layout solution of pipes in this group can be obtained in the same evolutionary ***,to eliminate the minor angle deviation of parallel pipes that would cause assembly stress in actual assembly,an accurate parallelization processing method based on the simulated annealing algorithm is ***,the simulation results on an aero-engine demonstrate the feasibility and effectiveness of the proposed method.

关键词： multiple pipe routing optimization algorithm aero-engine pipe grouping parallel layout

Knowledge and data jointly driven aeroengine gas path performance assessment method

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Chinese Journal of aeronautics 2024年第5期37卷 533-557页

作者： Zhe WANG Xuyun FU Rui ZHANG Zhengfeng BAI Xiangzhao XIA Wei JIANG Department of Mechanical engineering Harbin Institute of TechnologyWeihai 264209China Weihai Key Laboratory of Intelligent Operation and Maintenance Harbin Institute of TechnologyWeihai 264209China control system Design Laboratory AECC ShenYang Engine Research InstituteShenyang 110015China

aeroengines,as the sole power source for aircraft,play a vital role in ensuring flight *** gas path,which represents the fundamental pathway for airflow within an aeroengine,directly impacts the aeroengine's performance,fuel efficiency,and ***,timely and accurate evaluation of gas path performance is of paramount *** paper proposes a knowledge and data jointly driven aeroengine gas path performance assessment method,combining Fingerprint and gas path parameter deviation ***,Fingerprint is used to correct gas path parameter deviation values,eliminating parameter shifts caused by non-component performance ***,coarse errors are removed using the Romanovsky criterion for short-term data divided by an equal-length overlapping sliding ***,an Ensemble Empirical Mode Decomposition and Non-Local Means(EEMD-NLM)filtering method is designed to“clean”data noise,completing the preprocessing for gas path parameter deviation ***,based on the characteristics of gas path parameter deviation values,a Dynamic Temporary Blended Network(DTBN)model is built to extract its temporal features,cascaded with Multi-Layer Perceptron(MLP),and combined with Fingerprint to construct a Dynamic Temporary Blended AutoEncoder(DTB-AutoEncoder).Eventually,by training this improved autoencoder,the aeroengine gas path multi-component performance assessment model is formed,which can sufficiently decouple the nonlinear mapping relationship between aeroengine gas path multi-component performance degradation and gas path parameter deviation values,thereby achieving the performance assessment of engine gas path *** practical application cases,the effectiveness of this model in assessing the aeroengine gas path multi-component performance is verified.

关键词： Performance assessment aeroengine Fingerprint Gas path parameter deviation values Jointly drive

μ-Synthesis control with reference model for aeropropulsion system test facility under dynamic coupling and uncertainty

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Chinese Journal of aeronautics 2023年第10期36卷 246-261页

作者： Jiashuai LIU Xi WANG Xi LIU Meiyin ZHU Xitong PEI Song ZHANG Zhihong DAN School of Energy and Power engineering Beihang UniversityBeijing 100191China Zhongfa Aviation institute Beihang UniversityHangzhou 311115China Research institute of aero-engine Beihang UniversityBeijing 100191China Science and Technology on Altitude Simulation Laboratory AECC(Aero Engine Corporation of China)Sichuan Gas Turbine EstablishmentMianyang 621703China

Due to the dynamic coupling and multi-source uncertainties,it is difficult to accurately control the pressure and temperature of the aeropropulsion system Test Facility(ASTF)in the presence of rapid command and large *** paper presents the design ofμ-synthesis control to solve the *** incorporating the pressure ratio into the linear equation of the control valve,the modeling error of ASTF in the low frequency range is effectively ***,an uncertain model is established by considering various factors,including parameter variations,modeling error in the low frequency range,unmodeled dynamics,and changes in the working *** address the dynamic coupling,a diagonal reference model with desired performance is incorporated intoμ-***,all weighting functions are designed according to the performance ***,theμ-controller is obtained by using the standardμ-synthesis *** results indicate that theμ-controller decouples the pressure and temperature dynamics of *** with the multivariable PI controller,integral-μcontroller,and double integral-μcontroller,the proposedμ-controller can achieve higher transient accuracy and better disturbance ***,the robustness of theμ-controller is demonstrated by Monte Carlo simulations.

关键词： aeropropulsion system Test Facility(ASTF) Decoupling Robustness μ-Synthesis Uncertainty

Similitude design for the vibration problems of plates and shells： A review

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Frontiers of Mechanical engineering 2017年第2期12卷 253-264页

作者： Yunpeng ZHU You WANG Zhong LUO Qingkai HAN Deyou WANG Department of Automatic control and system engineering SheffieldUniversity Sheffield S13JD UK School of Mechanical engineering and Automation NortheasternUniversity Shenyang 110819 China School of Mechanical engineering Dalian University of TechnologyDalian 116023 China aecc Shenyang aero-engine institute Shenyang 110042 China

Similitude design plays a vital role in the analysis of vibration and shock problems encountered in large engineering equipment. Similitude design, including dimensional analysis and governing equation method, is founded on the dynamic similitude theory. This study reviews the application of similitude design methods in engineering practice and summarizes the major achieve- ments of the dynamic similitude theory in structural vibration and shock problems in different fields, including marine structures, civil engineering structures, and large power equipment. This study also reviews the dynamic similitude design methods for thin-walled and composite material plates and shells, including the most recent work published by the authors. Structure sensitivity analysis is used to evaluate the scaling factors to attain accurate distorted scaling laws. Finally, this study discusses the existing problems and the potential of the dynamic similitude theory for the analysis of vibration and shock problems of structures.

关键词： review dynamic similitude vibration modeltest