Sound Pressure Distribution of Car Interior and Influence of Wall

Abstract

In order to analyze how the sound emitted from the speaker of the car changes due to the influence of the wall, in the case of a box of rectangular parallelepiped (internal dimension 600 mm × 600 mm × 630 mm) with or without sound absorbing material (glass wool with a thickness of 50 mm) Experiments and calculations using the FE model were performed. The calculation results were able to reproduce the experimental results. It was also confirmed that the sound pressure level changes by about 20 dB above 500 Hz with and without glass wool. Next, we created a simple FE model that simulates the interior of an automobile, and the effect of sound absorption on the ceiling and floor, and the sound pressure level and sound pressure distribution when a sound absorbing material (PET material with a thickness of 50 mm)was added. The change of was measured using a real vehicle (Lexus UX) and analyzed by the FE model. It was confirmed that there was a difference in the sound pressure distribution from 100 Hz with and without PET.