Prediction of sound transmission loss of exhaust system particulate filter by homogenization method

Abstract

In the automobile market in recent years, the demand for vehicles with a small environmental load is increasing. in addition, with the stricter regulations on noise outside the vehicle, it is becoming more necessary to take measures against noise originating from the vehicle. the purpose of this study is to measure and predict the sound transmission loss of the actual exhaust pipe, focusing on the acoustic performance of the DPF・GPF. in accordance with ASTM E2611, the sound transmission loss of the actual exhaust pipe is actually measured, and the material properties of the DPF・GPF are acquired from the SEM image, etc., and the microscopic structural model is examined. the sound transmission loss is calculated from the calculation by the homogenization method. the validity of the evaluation method is verified by comparing the measured value and the calculated value.