基于一维/三维耦合模型的消声器声学性能预测研究

以某款商用车消声器为研究对象,针对一维线性消声器模型在高速气流影响下计算失准现象,研究一种基于一维/三维耦合模型的数值仿真分析方法;并结合实验数据对其结果进行验证。结果表明:随着发动机转速的提高,在某一转速后,一维消声器声学预测与实验数据不符,原因是在其内部产生了一维模型无法预测的气流再生噪声;基于Lighthill声类比理论的三维数值仿真,可较好地模拟空间域气动噪声场;并指出目标消声器再生噪声源产生域。一维/三维联合仿真可以实现真实情况下消声器声学性能的预测。

A Study on Acoustic Performance Prediction of Muffler Based on 1d/3d Coupling Model

The study object of this paper is a commercial car muffler.For the computing misalignment phenomenon of one dimensional linear muffler model in high-speed air flow,the paper developed a coupling model based on 1d/3d numerical simulation analysis method,and combined with the experimental data to validate the result. It turned out that: With the improvement of engine speed, after a certain speed, the acoustic prediction of one-dimensional muffler does not accord with the experimental data,because of the generation of regeneration noise which can not be calculate thought the one-dimensional model. Three-dimensional numerical simulation based on the theory of Lighthill acoustic analogy have a better way to simulate the aerodynamic noise field in the spatial domain and point out the field of regeneration noise in the muffler;The joint simulation of 1d/3d coupling modle can realize acoustic performance of muffler on real cases.