Computational Aeroacoustics Analysis of an Automotive Engine Exhaust System

Abstract

Traffic is a major source of environmental noise in modern day society. Subsequently, developments of new vehicles are subject to heavy governmental legislations. The major noise source on common road vehicles during acceleration is the flow noise caused by turbulent exhaust gas. The main objective of this work is to develop an appropriate Aeroacoustic simulation method to investigate the acoustic of sound at exhaust automotive muffler. The range of validity of the method is studied by comparing the results to measurements. The Computational Aeroacoustics (CAA) results are compared with an experimental test in a vehicle during its acceleration and the mean flow model of the muffler has a satisfactory mesh with a suitable inlet boundary provided by an engine dynamometer data. The present work describes a good agreement between computational and experimental approach for the Aeroacoustics behaviour of a specific configuration of exhaust muffler.