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Optimization of Muffler of Engines by Computers and Analysis Method

The low frequent noise of engine exhaust system is the main component of exhaust noise. Whether decreasing the noise of exhaust system or not has became a critical indicator of evaluating acoustic characteristics of mufflers. In order to reduce the noise of the engine exhaust system, this paper presents an improved muffler model, comparing the transmission loss of both the former muffler and the modified muffler. Then it establishes a coupled model with the engine and the muffler to analyze the noise of the engine exhaust system. Simulation results show that the performance of the modified muffler is superior to the former muffler.