Kinematic Characteristics Analysis And Optimization System Development For Variable Stator Vane Adjusting Mechanism Of Aero-Engine

Compressor variable stator vane adjusting mechanism are used to adjust the flow rate and angle of attack of the compressor.At different speeds,the adjusting mechanism needs to meet the requirements of the adjustment angle changes at all stages.The optimal design of the mechanism can make the stator vane in a reasonable adjustment angle and match the flow rate between the stages of the compressor,so as to effectively avoid the occurrence of stall of the aeroengine and improve the surge margin and stability of the compressor.At present,the optimization design of this mechanism is mainly through the methods of experiment and model prototype simulation.It is not only necessary to statistically analyze a large amount of experimental data and optimize the design process,but also time-consuming,labor-intensive,costly,and inefficient.In order to improve the efficiency of optimal design of VSV mechanism,the kinematics equation of the mechanism was derived.The optimization design system of the mechanism is developed based on UG platform,which takes the double relationship of the two-stage stator vane adjusting angular velocity as the optimization objective,combined with the adaptive genetic algorithm.Through the optimization value of the optimization system,the model is redesigned and its feasibility is verified by simulation.The main contents of this paper are as follows:(1)The mathematical model of VSV adjusting mechanism is established,and the first two-stage kinematics equations of the mechanism are theoretically deduced by using the spatial homogeneous coordinate method combined with the "rod removal method",which is mainly to analyze the change relationship of the two-stage static vane angle adjustment process.(2)According to the design requirements,the optimization objective function of VSV adjusting mechanism was established by parallel kinematics equations,and the length of adjustable ends and the angle between two ends of cranks were optimized by using adaptive genetic algorithm.Combined with the kinematics simulation module of UG software,the feasibility and accuracy of the algorithm are verified.(3)Based on the technology of secondary development on UG,the optimization design system of VSV adjusting mechanism is developed by using the C#language on UG platform.The system can dynamically adjust the design dimension value of the model mechanism and solve it in real time,and finally output the optimal result meeting the design requirements.(4)Based on the Lagrange equation of the second kind combined with the Euler angle and the Euler kinematics equation,the dynamics equation of the single cascade mechanism under ideal condition was derived,and a simple model of the mechanism was established in ADAMS to verify the correctness of the equation.(5)The flexible rocker arm is processed by ANSYS software and imported into ADAMS to replace the rigid rocker arm.The whole rigid-flexible coupling analysis of the single-stage VSV adjusting mechanism is carried out,and the shape variable nephogram of the rocker arm and the kinematic regularityof each component of the mechanism are obtained.