Research On Simulation And Improvement Of Flow And Sound Field Performance Of A Grader Muffler

The automotive engine’s exhaust noise is one of the main noise sources of automotive noise. The most effective way to control exhaust noise is to mount a muffler in exhaust system. The main research object of this paper is the exhaust muffler of grader which is used in roadway engineering. This paper is divided into three parts to study the performances of the muffler.First, the preliminary analysis about the acoustic and air flow performances of muffler was carried on based on the vehicle measurement and bench test, secondly,the simulation about muffler’s acoustic and air flow performances were processed with the software GT-power, acoustic software Vritual.Lab Acoustics and fluid dynamic software FLUENT. The performances of muffler’s acoustic and aerodynamic were studied, especially the influence on the performance of muffler by the main structural parameters of silencer, and some law between them. Finally, through the onedimensional acoustic model and the three-dimensional acoustic model simulation, and then with fast experimental verification of the assembly muffler, the structure of muffler was optimized and the performance was improved. After optimization, the insertion loss is increased by more than 2d B, and the pressure loss is reduced by 2.73 k Pa. The goal of improving both the acoustic performance and aerodynamic performance is achieved.In this paper, in the process of optimization of muffler, the muffler research method provides certain reference for the optimization of vehicle muffler and can be used to research and develop vehicle muffler.