Structure optimization of the main muffler in automobile based on the complex method

Automobile noise pollution is becoming more and more serious, and reducing emission and noise has become a common strategic choice for all countries to seize the commanding height of automobile market. With the help of STAR-CCM+, the main muffler in automobile is simulated and analyzed; by using the complex method this paper selects the design variables, defines the objective function, and is under the actual size constraints to obtain the optimized structural parameters of the main muffler. The empty pipe, the original main muffler and the optimized main muffler of the engine are tested separately in the vehicle. The results show that the noise of the optimized main muffler is 64.0dB(A) which reduces by 6.9dB(A) and 10.1dB(A) respectively compared with the original main muffler and the empty pipe, which verifies the optimization design is reasonable and effective.