Noise prediction method for automobile exhaust system

Abstract

The invention discloses a noise prediction method for an automobile exhaust system. The method comprises: establishing a sound-vibration coupling finite element calculation model between an in-vehiclesound cavity and a vehicle body in advance; pre-calculating an exhaust system lifting hook vibration transmission force-in-vehicle target point noise sound pressure transmission function in a frequency domain under different operation conditions, and storing the function into a database; pre-calculating an exhaust system lifting hook suspension point vibration displacement-lifting hook vibrationtransmission force transfer function in a frequency domain under different operation conditions, and storing the function into a database; establishing a kinetic finite element calculation model of the exhaust system, and calculating the vibration displacement at the suspension point of the lifting hook; and multiplying the vibration displacement by a vibration transmission force-in-vehicle targetpoint noise sound pressure transmission function and a vibration displacement-lifting hook vibration transmission force transmission function in a database to predict the noise sound pressure of thein-vehicle target point. Because the two transfer functions do not need to be calculated during noise prediction, the calculated amount is greatly reduced, and the prediction speed of the noise in thevehicle is improved.

Description

technical field [0001] The invention belongs to the technical field of automobile interior noise measurement, and in particular relates to a method for predicting noise caused by vibration of an automobile exhaust system. Background technique [0002] The noise inside the car is one of the important factors affecting the ride comfort. High noise can not only damage the physical and mental health of the occupants, but also cause rapid fatigue of the driver, which poses a great threat to the driving safety of the car. With the improvement of road conditions and the application of vehicle vibration ride comfort research results, vehicle interior noise plays an increasingly important role in evaluating vehicle ride comfort. At present, the research aimed at reducing the noise level in the car, improving the acoustic environment in the car, and improving the comfort of the car has become one of the research hotspots in the automotive field, and the rapid and accurate prediction ...

AI Technical Summary

Problems solved by technology

Due to the complex structure of the vehicle, in order to ensure the calculation accuracy, the acoustic-vibration coupling model of the acoustic cavity and the vehicle body usually contains a very high number of meshes and degrees of freedom, so a calculation takes a long time and the prediction efficiency is extremely low; in addition, the vehicle The operating conditions are changeable, and in-vehicle noise prediction results of multiple working conditions are required in actual projects

Existing vehicle interior noise prediction methods based on the acoustic-vibration coupling model of the interior acoustic cavity and the vehicle body face the bottleneck of low calculation efficiency of the finite element model

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