13th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
The paper describes an effort to numerically define the temporal dependences of mechanical stresses in a centrufugal compressor impeller caused by unsteady aerodynamic loads at nominal and precursor diffuser stall conditions. The object is a moderate Mach number shrouded wheel followed by a vaneless diffuser. The method applied is one-directional fluid-structure interaction with fully-transient fluid-flow- and structural simulations. The results indicate a clear distinction between stable and unstable flow-induced forces acting on the blades. On the other hand, the mechanical response predictions show rather marginal sensitivity to the operating point studied.