Prediction method for sound insulation performance of car front wall

Abstract

A prediction method for sound insulation performance of a car front wall is as follows: different thickness of steel plates are installed on sound insulation walls of reverberation chambers and anechoic chambers, and sound transmission loss STL (steel plate) of the different thickness of steel plates is tested; different thickness of different front wall panel materials are attached to the steel plates, and sound transmission loss STL (panel) of the different thickness of different front wall panel materials is tested; and combined sound transmission loss STL (combination) is calculated according to the sound transmission loss STL (steel plate) of the steel plates and the sound transmission loss STL (panel) of the front wall panel materials. Equivalent sound transmission loss of a front wall system is predicted by pre measurement of the sound transmission loss STL (steel plate) of the steel plates and the sound transmission loss STL (panel) of the different thickness of different front wall panel materials, during prediction of sound transmission loss of different front wall systems, the sound transmission loss can be calculated by direct extraction of corresponding pre measured data without cutting of the car front wall, customization of tooling, sealing, and other operation, and the work loading of sound transmission loss testing of the front wall system is greatly reduced.

Description

technical field [0001] The invention relates to the field of performance testing of automobile parts, in particular to a method for predicting the sound insulation performance of the front wall of an automobile. Background technique [0002] With the improvement of people's living standards, people's requirements for automobile performance are also getting higher and higher. In addition to the requirements for power, economy, and safety, the vibration and noise levels in the car interior are also important factors to measure the quality of the car. In recent years, the research on the noise, vibration and harshness (NVH) performance of automobiles has been paid more and more attention. [0003] As an important sound insulation system for automobiles, the front wall system can directly isolate the air noise from the engine compartment. The design of the front wall system has an important impact on the NVH performance of the vehicle. [0004] The sound insulation performance...

AI Technical Summary

Problems solved by technology

This method can be used to accurately test the sound insulation of the cowl system (the decibel difference between the incident sound energy on one side of the material and the transmitted sound energy on the other side is the sound insulation R of the material, also known as the transmission loss TL), but The test needs to cut the front wall of the car, custom tooling and high sealing conditions, and the workload is much larger than that of flat material testing

Moreover, if the designed cowl system does not meet the requirements and the design needs to be changed (such as changing the thickness of the sheet metal or the thickness of the cowl plate material), it is necessary to re-open the mold and measure according to the changed design, resulting in the cost and workload of design changes The increase of the design change makes the working process of the design change very slow. Moreover, because the design change is difficult to achieve a successful one time, it often requires multiple changes to obtain the optimal design, which further increases the design difficulty and workload.

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