Visualization of wave propagation in muffler
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This paper presents a prediction technique for wave propagation in muffler using Boundary Element Method (BEM). The results of the numerical calculation are compared with the plane-wave theory and also the experimental results. It is shown that at high frequencies the plane-wave theory does not yield correct results due to the occurrence of two- and three-dimensional wave motion. On the other hand, the BEM is able to predict the acoustic wave behavior in the high frequencies where the planewave theory fails.
The BEM uses a multi-domain technique to model complex mufflers, which may consist of cavities, tubes, perforates, and porous materials. Contour plots of sound pressure level inside the mufflers obtained from the BEM results are used to illustrate the principle of sound cancellation and to visualize the wave propagation behavior.
Keywordsmuffler BEM wave visualization noise
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