Rotor Vibration Behavior Due to IGV/Rotor Interaction in a Transonic Compressor with Fluid Structure Interaction Analysis

Abstract

A finite element method (FEM) structure solver is coupled with a finite volume method (FVM) Navier -Stokes solver at the fluid/structure interface and the coupled analysis is utilized to analysis the rotor vibration behavior of a transonic compressor. The computational fluid mesh is updated at every time step with an improved algebraic method. The flow solver is validated with experimental data at the IGV trailing edge and the fluid structure interaction (FSI) model is validated with a elastic cylinder flow at Re=200. With this newly developed FSI model, the compressor rotor vibration behavior was studied at different operating points and IGV/rotor axial spacing. The analysis indicates that the IGV wake is the main driving mechanism of the rotor blade forced vibration. The wake intensity is greatly influenced by its interaction with the rotor bow shock system. The intensity and relative position of the shock strongly affects the wake’s effect and blade vibration amplitude, accordingly. Proper design of the rot or leading edge shock and its location to the upstream wake can be used to reduce high cycle fatigue (HCF) due to periodic excitation and further improve the jet engine’s efficiency and performance.