Transonic Compressor IGV/Rotor Interaction Analysis Including Fluid Structure Interaction

Abstract

A commercial CFD solver, STAR-CD, is coupled with a structure FEA solver, CalculiX, to perform a fluid structure interaction (FSI) analysis for a transonic compressor IGV/Rotor configuration. Without FSI, the unsteady CFD prediction has good agreement at the IGV trailing edge, but the predicted interaction decays faster than the experimental results moving towards the inlet. With the FSI effect, the rotor blade vibration does not have a strong influence on the upstream IGV surface unsteady pressure for the current configuration. However, even with a small amount of displacement under cyclic blade row interaction, rotor blade surface unsteady pressure undergoes a significant variation of up to 40% higher when compared to the non-FSI simulation. The significance of including the higher fidelity of fluid/structure interaction in a transonic compressor analysis is that the rotor unsteady loading can be upwards of 40% higher with FSI than without it. Finally, the effect of the transonic IGV/rotor interaction on the unsteady flow physics was shown to be more significant than including the structural model alone. The different unsteady pressure levels can have significant effects on the durability and life of the transonic compressor from a high cycle fatigue consideration.