Design and verification of diesel generator exhaust muffler

The exhaust muffler is one of the most effective methods to control the exhaust noise of diesel generator. In this paper, a new type of impedance composite muffler is designed for the spectral characteristics of diesel engines and the shortcomings of existing mufflers. The main idea of the design is to reasonably design the key structures such as the length-diameter ratio, the insert-pipe, and the sound-absorbing material of the muffler under the condition of keeping the shape unchanged and low cost, so as to achieve the broadband noise reduction performance and improve the working efficiency of the diesel engine. The basic structure of the designed muffler is introduced. The transmission loss and pressure loss are numerically simulated and analyzed by finite element method, and the experimental verification is carried out. The results show that the structural parameters of the muffler have little effect on the transmission loss in the low frequency range, and the influence is more obvious in the middle- and high-frequency range. Compared with the existing muffler, the designed muffler significantly improves the noise reduction performance and reduces the exhaust back pressure.