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Sensitivity Analysis for Safety Design Verification of General Aviation Reciprocating Aircraft Engine

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Chinese Journal of Aeronautics 2012年第5期25卷 675-680页

作者： CAO Jiaokun ding shuiting Airworthiness Technologies Research Center Beihang UniversityBeijing 100191China

This paper presents an application of global sensitivity analysis for system safety analysis of reciprocating aircraft engine. Compared with local sensitivity analysis results, global sensitivity analysis could provide more information on parameter inter- actions, which are significant in complex system safety analysis. First, a deterministic aviation reciprocating engine thermody- namics model is developed and parameters of interest are defined as random variables. Then, samples are generated by Monte Carlo method for the parameters used in engine model on the basis of definition of factor distribution. Eventually, results from engine model are generated and importance indices are calculated. Based on the analysis results, design is improved to satisfy the airworthiness requirements. The results reveal that by using global sensitivity analysis, the parameters could be ranked with respect to their importance, including first order indices and total sensitivity indices. By reducing the uncertainty of parameters and adjusting the range of inputs, safety criteria would be satisfied.

关键词： sensitivity analysis safety analysis airworthiness reciprocating aircraft engine design verification

Identification of key factors affecting the failure of aviation piston engine turbochargers based on an improved correspondence analysis-polar angle-based classification

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Chinese Journal of Aeronautics 2021年第5期34卷 466-484页

作者： Mengyao BAO shuiting ding Guo LI Civil Aviation Management Institute of China Beijing 100102China Aircraft|Engine Integrated System Safety Beijing Key Laboratory Beihang UniversityBeijing 100083China

Turbocharging is an efficient approach for addressing power reduction and oil consumption increase in aviation piston engines during high-altitude ***,a turbocharger significantly increases the complexity of a power system,and its considerably complex matching relation with the engine results in a coupling of failure *** analytical methods are hard to identify failure-inducing ***,safety issues are becoming increasingly *** study focuses on methods for identifying failure-inducing factors.A whole-machine system model is established and validated through *** response surface method is employed to further abstract the system simulation model to a surrogate model(average error:~3%)in order to reduce the computational cost while ensuring *** this basis,an improved Correspondence Analysis(CA)-Polar Angle(PA)-based Classification(PAC)is proposed to identify the key factors affecting the failure mode of *** identification method is based on the row profile coordinates G varying with the numerical deviations of the key factors,and is capable of effectively identifying the key factors affecting the *** a validation example,this method identifies the diameter of the exhaust valve(e_(2))as the primary factor affecting the safety margin for each work boundary.

关键词： Failure-inducing factors Improved correspondence analysis Polar angle Turbochargers Whole-machine system model

Time-triggered State-machine Reliable Software Architecture for Micro Turbine Engine Control

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Chinese Journal of Aeronautics 2012年第6期25卷 839-845页

作者： ZHANG Qi XU Guoqiang ding shuiting School of Transportation Science and Technology Beihang University Beijing 100191 China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Beihang University Beijing 100191 China

Time-triggered （TT） embedded software pattern is well accepted in aerospace industry for its high reliability. Fi-nite-state-machine （FSM） design method is widely used for its high efficiency and predictable behavior. In this paper, the time-triggered and state-machine combination software architecture is implemented for a 25 kg thrust micro turbine engine （MTE） used for unmanned aerial vehicle （UAV） system; also model-based-design development workflow for airworthiness software directive DO-178B is utilized. Experimental results show that time-triggered state-machine software architecture and development method could shorten the system development time, reduce the system test cost and make the turbine engine easily comply with the airworthiness rules.

关键词： airworthiness time-triggered finite-state-machine model-based-design turbine engine control

Effects of swirl and hot streak on thermal performances of a high-pressure turbine

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Chinese Journal of Aeronautics 2023年第5期36卷 250-267页

作者： Shenghui ZHANG shuiting ding Peng LIU Tian QIU National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power EngineeringBeihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Advanced civil aero-engines tend to adopt lean burn combustors to meet emission *** exit of a lean burn combustor experiences highly non-uniformities in both temperature(Hot Streak,HS)and flow(swirl).This paper presents a numerical investigation on the behaviors of a High-Pressure(HP)turbine under a combined effect of swirl and hot *** investigation was conducted on a GE-E3 HP turbine with unsteady numerical simulations,which considered the realistic clocking position of the HP Nozzle Guide Vane(NGV)relative to the *** influences of swirl orientations on the HS migration and thermal performances on the blade surface were *** indicate that,inside the NGV passage,the swirl’s induced incidence angle effect dominates the HS radial *** transversal movement of HS follows the cross flow and thus makes itself approach the Suction Side(SS)and keep away from the Pressure Side(PS)as passing through the NGV,so that HS near the SS is more influenced by the incidence angle effect than that near the *** for the heat transfer,swirl affects the Heat Transfer Coefficient(HTC)on the NGV’s PS and SS mainly through the incidence angle *** from the NGV,the inlet swirl and HS have limited effect on the HTC on the rotor blade’s PS,while on the rotor blade’s SS,the original vortex system dominates;therefore,the inlet non-uniformities merely enhance the HTC on the SS rather than alter its distribution characteristics.

关键词： High-pressure turbine Hot streak Thermal performances Swirl Orientations Vortex

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

Effect of scavenge port angles on flow distribution and performance of swirl-loop scavenging in 2-stroke aircraft diesel engine

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Chinese Journal of Aeronautics 2021年第3期34卷 105-117页

作者： Zheng XU Fenzhu JI shuiting ding Yunhai ZHAO Yu ZHOU Qi ZHANG Farong DU School of Energy and Power Engineering Beihang UniversityBeijing 100083China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beihang UniversityBeijing 100083China School of Transportation Science and Engineering Beihang UniversityBeijing 100083China Beijing Key Laboratory for High-efficient Power Transmission and System Control of New Energy Resource Vehicle Beihang UniversityBeijing 100083China

Swirl-Loop Scavenging(SLS) improves the performance of 2-stroke aircraft diesel engine because the involved swirl may not only benefit the scavenging process, but also facilitate the fuel atomization and combustion. The arrangement of scavenge port angles greatly influences incylinder flow distribution and swirl intensity, as well as the performance of the SLS engine. However, the mechanism of the effect and visualization experiment are rarely mentioned in the literature. To further investigate the SLS, Particle Image Velocimetry(PIV) experiment and Computational Fluid Dynamics(CFD) simulation are adopted to obtain its swirl distribution characteristics, and the effect of port angles on scavenging performance is discussed based on engine fired cycle simulation. The results illustrate that Reynolds Stress Turbulence model is accurate enough for in-cylinder flow simulation. Tangential and axial velocity distribution of the flow, as well as the scavenging performance, are mainly determined by geometric scavenge port angles ageom and βgeom . For reinforcement of scavenging on cross-sections and meridian planes, ageomvalue of27° and βgeom value of 60° are preferred, under which the scavenging efficiency reaches as high as 73.7%. Excessive swirl intensity has a negative effect on SLS performance, which should be controlled to a proper extent.

关键词： 2-Stroke Aircraft diesel engine Computational Fluid Dynamics(CFD) Particle Image Velocimetry(PIV) Scavenge port angles Swirl-Loop Scavenging(SLS)

Review of the development of the probabilistic damage tolerance assessment of life-limited parts in compliance with the airworthiness regulations

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Propulsion and Power Research 2023年第3期12卷 297-321页

作者： shuiting ding Huimin Zhou Junbo Liu Xingyu Zhang Guo Li Aircraft/Engine Integrated System Safety Beijing Key Laboratory School of Energy and Power EngineeringBeihang UniversityBeijing 100191China Civil Aviation University of China Tianjin 300300China Tianmushan Laboratory Zhejiang 311100China

Probabilistic damage tolerance is a critical method to understand and communicate risk and *** paper reviews recent research on the probabilistic damage tolerance design for life-limited *** vision of the probabilistic damage tolerance assessment is *** core parts of the probabilistic damage tolerance method are introduced separately,including the anomaly distribution,stress processing and zone definition,fatigue and fracture calculation method,probability of failure(POF)calculation method,and the combination with residual stress induced by the manufacturing *** above currently-available risk assessment methods provide practical tools for failure risk predictions and are applied by the airworthiness ***,new problems are exposed with the development of the *** time-consuming anomaly distribution derivation process restricts the development of the anomaly distribution,especially for the developing aviation industries with little empirical ***,the strong transient characteristic is prominent because of the significant temperature differences during the take-off and climbing *** complex loads then challenge the fatigue and fracture calculation ***,high computational efficiency is required because various variables are considered to calculate the ***,new technologies for the probabilistic damage tolerance assessment are provided,including the efficient anomaly distribution acquisition method based on small samples,the zone definition method considering transient process,and stress intensity factor(SIF)solutions under arbitrary stress distributions combined with the machine learning ***,an efficient numerical integration method for calculating failure risk based on the probability density evolution theory is ***,the influence of the manufacturing process on residual stress and the failure risk of the rotors is *** development of the probabi

关键词： Probabilistic damage tolerance assessment Life-limited parts Aero-engine rotors Hard alpha(HA)anomaly distribution Hole feature Transient process Crack propagation Stress intensity factor(SIF)

Bi-Fo time scaling method in the numerical simulation of transient conjugate heat transfer

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Propulsion and Power Research 2021年第3期10卷 209-223页

作者： Yu Shi shuiting ding Tian Qiu Chuankai Liu Shenghui Zhang School of Energy and Power Engineering Beihang UniversityBeijing100191China Research Institute of Aero-Engine Beihang UniversityBeijing102206China

Reliable transient thermal analysis plays a very important role in the engine safety *** conjugate heat transfer simulation is an important way of temperature *** there exists a great disparity in the time scales between solid conduction and fluid *** calculation cost of transient conjugate heat transfer analysis is very huge because of the tiny time step of computational fluid *** Bi-Fo time scaling method is proposed to improve the computational efficiency of transient conjugate heat *** the one hand,this method carries out a similar transformation on solid heat conduction,scaling the calculation time with the product of density and specific heat capacity to maintain the consistency of Fourier *** the other hand,it takes very short time for the fluid domain to recover stability after a boundary *** on the above characteristic,the flow time is directly compressed to the same as that of the solid *** is verified by Mark II vane that increasing the solid thermal diffusivity can reduce the time scale of heat *** the situation of rapidly stable flow field,scaling flow time does not affect the solid thermal boundary under corresponding dimensionless *** the application scope,the Bi-Fo time scaling method can greatly reduce the time cost of transient conjugate heat transfer simulation while maintaining the accuracy of transient temperature analysis.

关键词： Transient Temperature analysis Conjugate heat transfer Similar transformation Time scaling

Investigation into gas lubrication performance of porous gas bearing considering velocity slip boundary condition

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Friction 2022年第6期10卷 891-910页

作者： Xiangbo ZHANG shuiting ding Farong DU Fenzhu JI Zheng XU Jiang LIU Qi ZHANG Yu ZHOU School of Energy and Power Engineering Beihang UniversityBeijing 100191China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China

Porous gas bearings(PGBs)have a proactive application in aerospace and *** study investigates the gas lubrication performance of a PGB with the condition of velocity slip boundary(VSB)owing to the high Knudsen number in the gas *** Darcy-Forchheimer laws and modified Navier-Stokes equations were adopted to describe the gas flow in the porous layer and gas film region,*** improved bearing experimental platform was established to verify the accuracy of the derived theory and the reliability of the numerical *** effects of various parameters on the pressure distribution,flow cycle,load capacity,mass flow rate,and velocity profile are demonstrated and *** results show that the gas can flow in both directions,from the porous layer to the gas film region,or in *** load capacity of the PGB increases with an increase in speed and inlet pressure and decreases with an increase in *** mass flow rate increases as the inlet pressure and permeability ***,the simulation results using VSB are in agreement with the experimental results,with an average error of 3.4%,which indicates that the model using VSB achieves a high *** simulation results ignoring the VSB overrate the load capacity by 16.42%and undervalue the mass flow rate by 11.29%.This study may aid in understanding the gas lubrication mechanism in PGBs and the development of novel gas lubricants.

关键词： porous gas bearing(PGB) velocity slip boundary(VSB) numerical simulation gas lubrication flow characteristics