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Chinese Journal of aeronautics 2022年第11期35卷 264-276页

作者： Shaojing DONG Yufan FANG Wentong HU Xiuli SHEN Gaoxiang CHEN School of Energyand Power engineering Beihang UniversityBeijing 10083China Beijing Key Laboratory of aero-engine Structure and Strength Beihang UniversityBejing 100083China Jiangxi Research Institute Beihang UniversityNanchang 330096China Navigation and Control Technology Research Institute of China Ordnance Industries Beijing 100089China Research Institute of aero-engine Beihang UniversityBeijing 100083China

In aero engine design, determining whether the preliminary design will have disruptive effects on the detailed design is the key to multidisciplinary design optimization in the preliminary design stage. In order to adapt to the non-orthogonal parameter value range caused by the selfconstrained parametric modeling method, a non-orthogonal space mapping method that maps the optimal Latin hypercube sampling points of the traditional orthogonal design space to the non-orthogonal design space is proposed. Based on the logical regression method in machine learning field, a kind of feasible domain boundary identification method is employed to identify whether the sample spatial response meets the relevant criteria. The method proposed in this paper is used to identify and analyze the key technologies of the high-pressure turbine mortise joint structure. It is found that the preliminary design of the aero engine may lead to the failure to obtain a mortise joint structure meeting the design requirements in the detailed design stage. The mortise joint structure needs to be pre-optimized in the preliminary design stage.

关键词： aero engine Disruptive design Flow pass multidisciplinary optimization Pre-identification Preliminary design phase

Optimal location and shape definition of elliptical ventilation openings on aero engine turbine rotors with stress concentration effect

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Chinese Journal of aeronautics 2022年第1期35卷 388-397页

作者： Haibing YU Tiefeng CHEN Yanjie QIU AECC Commercial Aircraft engine Co. LTDShanghai 200241China

The aero engine turbine rotors are under strong centrifugal load and the highest thermal load.The ventilation openings on the rotors are inevitable,because air flow need to pass through them to cool the temperatures down and keep the air pressure balanced in internal aero engine.The ventilation openings will lead to stress concentration effect.In this paper,the stress concentration factor of elliptical opening on rotating disc is deduced by superposition method.How to define the optimal location and shape of the elliptical opening on rotating disc to decrease the stress concentration effect has been investigated specifically.The reliability and accuracy of the theoretical deviation process is verified by Finite Element Method(FEM).The process of how to obtain the optimal location of the elliptical ventilation opening with particular shape on turbine sealing disc is described as an engineering application case.The investigation provides sufficient theoretical support for optimal location and shape definition of elliptical ventilation opening on aero engine rotors with stress concentration effect by pure mechanics consideration.

关键词： aero engine Elliptical ventilation opening Finite Element Method(FEM) Rotor Stress concentration

Development of acoustic liner in aero engine: A review

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Science China(Technological Sciences) 2020年第12期63卷 2491-2504页

作者： MA XuQiang SU ZhengTao Aviation Key Laboratory of Science and Technology on Materials and Application Research for Vibration and Noise Reduction AECC Beijing Institute of Aeronautical MaterialsBeijing 100095China

Noise reduction for aircraft engine has attracted great concern due to the strict noise control regulation nowadays. Conventional perforated sheet-over-honeycomb acoustic liners have been widely used to attenuate turbofan engine noise. To dampen the broadband noise and resist the harsh service conditions with high temperature and pressure in modern turbofan engine,new acoustic liner concepts are proposed and evaluated in the latest decade. In this review,available studies regarding the recent development of liners are gathered. The paper starts with the introduction of acoustic absorption mechanism of local-reacting and extended-reacting liners. The progress of novel passive liners(e.g.,mesh-cap liner,variable-depth liner,metal foam liner,hybrid liner,etc.) is summarized. Furthermore,adaptive liners with tunable geometry dimension or bias flow are illustrated in details.Metamaterial is also mentioned as a hot candidate in the next generation of acoustic liners. Finally,this review identifies benefits and some technical challenges with the goal of unveiling the potential of novel acoustic liner technologies in aero engine.

关键词： aero engine noise acoustic liner Helmholtz resonators composites

Research on an Arc Air-Lubricating Oil Radiator Equipped in Internal Surface of Air Intake for the aero engine

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Journal of Thermal Science 2020年第3期29卷 687-696页

作者： CAI Huikun WENG Zeju LIAO Yidai GU Kaixuan WANG Junjie Department of Mechanical and Electronic engineering of Xiamen University Xiamen UniversityXiamen 361102China CAS Key Laboratory of Cryogenics Technical Institute of Physics and Chemistry of the Chinese Acadermy of SciencesBejing 100190China

Due to huge-power aircraft development and more electronic devices applied onboard,high heat flow density and uneven thermal distribution are becoming new problems.One new try is adding an air-lubricating oil radiator as the secondary cooling component but there are still few reports on its research.Therefore,this paper proposes a newly-design plate-fin air-lubricating oil radiator different from tube-fin or shell-tube conventionally used in previous engine system.This radiator is arc,and equipped in internal surface of air intake.Numerical and experimental analyses were carried out on fin performance.Their results agreed well with average error of 13%on thermal resistance.Then heat and flow behaviors of oil side were presented with different structures and sizes of flowing passage.According to all research,optimized radiator is gained with fin spacing of 3.76 mm,fin thickness of 2 mm,single flowing path with width of 13 mm and gradient inlet and outlet.Its heat dissipation of 28.35 k W and pressure loss of 2.2 MPa can meet actual working requirements.The research proves an air-lubricating oil radiator with arc structure and layout mode of internal surface to be feasible,which is a new but efficient cooling scheme and can lead to an innovative but wide use in modern aircrafts.

关键词： aero engine air-lubricating oil radiator arc plate-fin radiator oil flowing path internal surface of air intake

An Interval-Valued Prediction Method for Remaining Useful Life of aero engine

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An Interval-Valued Prediction Method for Remaining Useful Li...

A Fast Method to Calculate the Oil Droplet Velocity in aero engine Bearing Chambers

第三十九届中国控制会议

作者： Bingce Zhang Degang Wang Wenyan Song Shuo Zhang Sida Lin School of Control Science and engineering Dalian University of Technology School of Economics Dongbei University of Finance and Economics

aero engine is the core power unit of aircraft. A satisfactory prediction of remaining useful life（RUL） for an aero engine can ensure timely replacement and maintenance of engine and can avoid huge loss caused by engine failure during flight mission. In this paper, a multi-layer perceptron（MLP） prediction model based on information granular theory is proposed to estimate the RUL interval of aero engine. Firstly, the principal component analysis（PCA） method is considered to reduce dimension of inputs due to large number of sensor measurements of aero engines. Then a method to find the degradation interval of engine by the principle of justifiable granularity is designed, and the expected maximum RUL of each engine can be determined dynamically. Furthermore, a multi-layer perceptron is used to find the relation between aero engine sensor measurements and remaining useful life, by which the RUL interval of aero engine is obtained. Some numerical simulations show that the proposed model can obtain satisfactory performance.

关键词： aero engine remaining useful life interval information granule

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International Journal of Plant engineering and Management 2014年第3期19卷 173-179页

作者： FANG Long CHEN Guo-ding SUN Heng-chao School of Mechanical engineering Northwestern Polytechnical University

The oil droplet velocity in an aero engine bearing chamber can determine the initial film state which is the fundament for lubrication design and heat analysis. This paper studied the droplet motion in a respective aero engine bearing chamber and obtained a fast method to calculate the droplet velocity by an analytical method. Comparing the velocity results calculated by the fast method with those from the literatures by the numerical method under different operating conditions, the method proposed in this paper is confirmed to be fast and reliable. The effects of operating conditions on droplet velocity are obtained at the same time. This study contribute to follow-up research work on droplet deposition properties in aero engine bearing chambers

关键词： aero engine bearing chamber fast method droplet velocity

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 problem.Secondly,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 inducer.Finally,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is analyzed.The 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 test.Based on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately captured.The 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

A Hydrodynamic Model for Dimpled Mechanical Gas Seal Considering Interaction Effect

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Transactions of Nanjing University of aeronautics and Astronautics 2015年第4期32卷 438-445页

作者：时礼平黄巍王晓雷 College of Mechanical and Electrical engineering Nanjing University of Aeronautics and Astronautics College of Mechanical engineering Anhui University of Technology

The mechanical gas seal of aero engine has to face the problems of high wear rate and short lifetime.Surface texture has shown beneficial effects over the tribological characteristics.Here,a hydrodynamic model for dimpled annular area of mechanical gas seal considering the″interaction effect″between adjacent dimples is developed based on the Reynolds equation.Different multi-row columns are chosen and the dimensionless pressure in radial and circumferential directions is calculated.The results indicate that the″interaction effect″is more obvious in the circumferential direction than in the radial direction,even when the area and depth of the dimples are same.Moreover,for the 5×5column,the dimensionless average pressure considering the″interaction effect″increases by45.41% compared with the 1×5column.Further analysis demonstrates that the model with the 5×5column can be more reasonable with the consideration of reducing the calculation error caused by boundary conditions to investigate the hydrodynamic effect for dimpled mechanical gas seal.

关键词： surface texture mechanical gas seal hydrodynamic effect interaction effect aero engine

Effects of Tightening Torque on Dynamic Characteristics of Low Pressure Rotors Connected by a Spline Coupling

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Transactions of Nanjing University of aeronautics and Astronautics 2017年第5期34卷 514-523页

作者： Chen Xi Liao Mingfu Li Quankun Institute of Monitoring and Control for Rotating Machinery and Wind Turbines School of Power and Energy Northwestern Polytechnical University Xi'an 710129 P.R. China

A rotor dynamic model is built up for investigating the effects of tightening torque on dynamic characteristics of low pressure rotors connected by a spline coupling.The experimental rotor system is established using a fluted disk and a speed sensor which is applied in an actual aero engine for speed measurement.Through simulating calculation and experiments,the effects of tightening torque on the dynamic characteristics of the rotor system connected by a spline coupling including critical speeds,vibration modes and unbalance responses are analyzed.The results show that when increasing the tightening torque,the first two critical speeds and the amplitudes of unbalance response gradually increase in varying degrees while the vibration modes are essentially unchanged.In addition,changing axial and circumferential positions of the mass unbalance can lead to various amplitudes of unbalance response and even the rates of change.

关键词： tightening torque dynamic characteristics spline coupling low pressure rotor aero engine