Modelling and Numerical Simulation of the Noise Generated by Automotive Turbocharger Compressor

We study in detail the flow mechanism, the aeroacoustic sources and its sound propagation in turbochargers by applying numerical simulations based on an appropriate aeroacoustic formulation. Thereby, we consider Lightill’s analogy for the investigation of the different noise mechanisms. The flow inside a turbocharger is highly turbulent and compressible. Thus, all three terms of Lighthill’s tensor are examined: (1) the Reynolds stress term, (2) the excess term and (3) the viscosity term. The investigations will be performed both in time and frequency domain, and we do a detailed study of the influences of different spatial and temporal discretizations.