Simulation of the vibro-acoustic response of a truck cabin in low frequency range including the effect of the acoustic treatments; comparison with experiments
Abstract
The low frequency noise in a truck cabin (typically below 300Hz) is a strong component of the interior noise comfort. In the development of a numerical process to predict the interior noise in this frequency range, the simulation of the vibro-acoustic response of the cabin is a step to be developed. This paper summarizes the work done to correlate a numerical method for the vibro-acoustic response of the cabin taking into account the effect of the acoustic treatments. One constraint is to keep a modal scheme although the acoustic treatments are heavily damped and not very suited to be solved with this scheme. The process is based on the modal extraction of structure and cavity modes, followed by the calculation of acoustic treatments impedances which are projected into the modal space. The complete vibro-acoustic response for a given excitation can then be computed with a modal frequency response. The paper presents a measurement campaign performed to get reference measured data and details the different parts of the model. Comparisons between simulated and measured Vibration Transfer Functions and Noise Transfer Functions are presented. The good correlation obtained assesses the validity of the method and the modelling.