Analysis of flow-induced vibrations in turbomachinery by mapping of complex fluid pressures
In this paper we introduce a mapping procedure which facilitates the simulation of flow-induced vibrations in turbomachinery. The transient steady state pressure fluctuations in the flow field (which excite vibrations) are computed in the frequency domain by what are generally referred to as ""harmonic CFD"" methods where the pressure oscillations are expressed by complex amplitudes. They are mapped using the Fraunhofer software FSIMapper to a structural vibration analysis. A main focus lies in the provision of mapping methods for cyclic symmetric models. The process provides a fast numerical assessment of flow-induced vibrations where the resulting vibration amplitudes can be used for realistic fatigue estimations of flow-excited turbine components. The procedure is applied to a ceramic impeller of a micro gas turbine.