Motion Characteristics Analysis And Optimization System Development Of Multi-stage Jointly Adjusting Mechanism Of Aero-engine Variable Stator Vane

An aero engine is an indispensable and core equipment in aircraft.It powers the aircraft.The performance of aero engine directly affects the performance of the aircraft.Compressors are very important components in engines.It has a direct impact on engine performance.In order to achieve stable operation of the compressor in different states of the engine,a multi-stage jointly adjusting mechanism of variable stator vane(VSV)is generally used to adjust the rotation of the stator vane to improve the stability of the compressor.Therefore,the adjustment of the stator vane’s rotation law by the jointly adjusting mechanism directly affects the performance of the aircraft.Whether it is the mobility of military aircraft or the safety of civil aircraft,there are increasing demands on the performance of engines.Especially during the smooth transition between different flight conditions.Therefore,people pay more and more attention to the structure research and optimization design of the jointly adjusting mechanism.At present,the kinematic characteristics of the joint adjustment mechanism are mainly studied through simulation software.Lack of theoretical analysis.In addition,the optimization solutions are all serial optimizations,that is,the other stages are optimized based on the zeroth stage,not a joint optimization between multiple stages.Comparatively speaking,theoretical analysis is more persuasive.And the use of equations makes it easier to optimize the design of the joint adjustment mechanism.It can significantly improve the speed and accuracy of optimization solutions,improve design efficiency,and shorten design cycles.Joint optimization between multiple levels can significantly expand the range of feasible solutions.And it provides more options for the structural design of the jointly adjusting mechanism.The main research contents of this topic are as follows:(1)Derivation of kinematics equations for two-stage jointly adjusting mechanism.Based on the graphic method,the homogeneous coordinate method and combined with MATLAB software,the zeroth-stage kinematics equation,the first-stage kinematics equation,and the two-stage rocker(static stator blade)rotation relation equation are derived.(2)Kinematic characteristics analysis and optimization of two-stage jointly adjusting mechanism.Based on the derived kinematics equations,given the structural parameters,the rotation laws of the rocker arms(static blades)at various levels and the rotation rules between the two-stage rocker arms(static blades)are analyzed under specific inputs.The two-stage crank(the adjustable length of the crank,the angle between the adjustable end and the fixed end)is optimized.The purpose is,under the fixed input,to make the rotation angle of the first stage vane is twice that of the zeroth stage.And the rotation speed of the rotation angle of the zeroth stage vane is also twice that of the zeroth stage.(3)Development of an automatic optimization system for a two-stage jointly adjusting mechanism.Based on the UG motion simulation module,a simulation optimization system is developed for the two-stage jointly adjusting mechanism.And an analytical optimization system is developed for the two-stage jointly adjusting mechanism based on the derived kinematic equation.(4)Dynamic characteristics analysis of single-stage jointly adjusting mechanism.the motion of the connecting rod is analyzed using euler angles.The dynamic equation of the single-stage jointly adjusting mechanism is derived using the lagrange equation.Using the derived equations,the motion laws of the single-stage jointly adjusting mechanism is analyzed.