Global Dimensional Optimization for the Design of Adjusting Mechanism of Variable Stator Vanes

Abstract

：In order to avoid the problem of compressor surge, the variable stator vane (VSV) needs to follow the rules established by hydromechanics. The VSV is normally composed of several connected stages and actuated by one adjusting mechanism that contains several coupled spatial linkage mechanism units. It is difficult to perform the dimensional synthesis of the VSV adjusting mechanism since this mechanism is a coupled system of the several spatial linkage units and the rules established by hydromechanics are also complicated. Currently, a divide and conquer method is applied to synthesize the dimensions of the VSV adjusting mechanism by synthesizing the spatial linkage mechanism units one by one, hereafter the global optimization is unable to be achieved. In order to improve the VSV's adjustment accuracy, a novel global dimensional synthesis method is proposed by combining the forward kinematics (FK) and inverse kinematics (IK) considering the analytical solvability of the FK and IK models. An efficiently global optimization is achieved firstly to provide the initial solution by using the analytical IK model and then a global optimization of high accuracy is achieved by searching from the initial solution based on the numerical FK model. A case study is given to demonstrate the proposed method.