Analysis And Research Of The Engine Exhaust System Simulation

Recent years, noise pollution, caused by the rapid development of the automobile industry, is becoming a global issues. People pay close attention to some aspects such as the riding comfort at the same time. As an important factor to worsen the riding comfor, noise produced by the exhaust system must be strictly controled and attacts more and more attention.The exhaust noise produced by automobile engine is one of the main noise sources. Iinstallig an exhaust muffler is an effective way to reduce exhaust noise.In this paper, the contents include the basic theory of acoustics, the source of noise and methods of noise control, generating mechanism of automotive exhaust noise, type and evaluation index of automotive muffler. status and methods of the muffler research. From the analysis of the working principle of the muffler and the main indicators of its performance. We come to a conclusion of the muffler analysis with discrete numerical simulation.Finite volume method, a simulation based on the discrete numerical analysis, is the theoretical basis of acoustic software. about the simulation of the muffler, I choose the fluid simulational software FLUENT to do it, analyze the internal fields such as the flow field and the pressure field of the modling, generate the pressure loss curve, and evaluate the fluid performance of the muffler. Considering the requirements and indicators of the muffler. remodify the model, compare the remodified muffler to the original one. From the comparison, pressure loss of the model modified is lower than the original one. Flow field distribution is more uniform. The outer wall of noise power decrease.This prove the modification is reasonable and successful.