In-vehicle Analysis of Powertrain-Induced Noise Using FRF Substructures

Abstract

Numerical analysis plays a significant role in the development of passenger comfort in modern vehicles. Customer perception of quality and comfort is largely influenced by the vibro-acoustic properties of a vehicle. Numerical simulation models of sufficient quality for predicting these characteristics are highly complicated and large numbers of eigenvalues are necessary to enable accurate analysis through the required frequency-range. It follows that extensive computational resources are required and calculation times are long.

This paper describes the generation and use of so-called FRF-Substructures, a modern technique in model reduction for frequency-response analysis in Nastran. Using a practical example of a Mercedes-Benz S-Class model it is shown how FRF-Substructures can significantly increase the efficiency of frequency-response calculations. This enables the evaluation of multiple model variations and complex load-cases in a reasonable time. Further, the advantages of FRF-Substructures are shown by comparison with the traditional superelement approach. Finally, a brief outlook on further uses of the FRF-Substructure technique are addressed.