The Numerical Simulation Research On Acoustic And Resistance Performance Of Exhaust Muffler Of Automotive

The exhaust noise of engine is one of the main noise sources of automobile noise. At present,the most effective measure to control exhaust noise is using muffler in exhaust system. The exhaust muffler is a noise reduction device,which prevents the spread of noise and allows airflow through it,it reduces the exhaust noise but also increases exhaust resistance,affects the power and oil-consume performance of engine. In serious case even affects the normal operation of the engine. So designing a muffler with high acoustic attenuation performance and low resistance loss has been an important subject on exhaust noise control.In this thesis,three-dimensional numerical simulation method is used to do some research on acoustic and resistance performance of exhaust muffler. The three-dimensional numerical simulation method can simulate the exhaust muffler performance accurately and take the influence of several outside factors into account. So it is an effective method to an improved design. Firstly,study the acoustic and resistance performance of basic anechoic constructions,focus on the influence of structure parameters on the performance of muffler;Secondly,analyze the influence of the structure of tail pipe on the performance of muffler;Finally, analyze the acoustic and resistance performance of exhaust muffler of a sedan car through three-dimensional numerical simulation method,propose measures to improve the performance of muffler.Three-dimensional numerical simulation method can shorten the development cycle,reduce the cost and improve the quality of product. It is of important instructional significance for the design and improvement of muffler.