Application of the Wave Based Technique for the exterior acoustic field of a simplified car mock-up

Recent years have seen an increase in the importance of analyzing the exterior noise generated by vehicle power trains, a trend which is expected to continue in light of the anticipated stringent update of the ISO 362 pass-by noise standard. To reduce exterior noise, there are a variety of analytical and computational methodologies available that can help design engine shields and other thermoacoustic trim parts that are positioned inside the engine bay. One such method is the Wave Based Technique (WBT), which uses the exact solutions of the governing differential equation instead of simple polynomial shape functions. Since a fine discretization is no longer required, the resulting wave based models are substantially smaller than their element-based counterparts. This paper describes a proposed application of the WBT to a car mock-up and compares the results with those achieved via the Boundary Element method and the Perfectly Matched Layer method.