Angle-Regulating Rule of Guide Vanes of Variable Geometry Turbine Adjusting Mechanism

Abstract

In recent years, more and more attention has been paid to research on variable geometry turbine engines with the increasing requirement of engine performance. Variable geometry turbine technology can significantly improve the operating performance of aero engines. Adjusting the working angle of the turbine guide vane can change the thermodynamic cycle of the engine operation, so that the turbine can respond to different engine operating conditions. Variable geometry turbines work in harsh environments. Therefore, the design of the variable geometry turbine needs to consider the effect of thermal deformations of the mechanism on operational stability. There are few research studies on variable geometry turbine adjusting mechanisms. This paper established the numerical calculation models of two adjusting mechanisms by integrating fluid mechanics, heat transfer, and dynamic theories, which are paddle and push–pull rod mechanisms. The models were applied to study the effects of components’ thermal deformations and flexible bodies on the motion characteristics of the adjusting mechanism. Furthermore, the performance of the two adjusting mechanisms was compared. The calculation results show that the paddle rod adjusting mechanism can accurately adjust the angles of guide vanes. The paddle rod adjusting mechanism has a larger driving stroke and smaller driving force than the push–pull rod adjusting mechanism. The paddle adjustment mechanism was better suited to the operational requirements of the variable geometry turbine. The research results of this paper are relevant to the design of variable geometry turbine regulation structures.