Investigation on structure parameters and performances of combined muffler

The muffler combined with jet and impedance is designed to control exhaust noise of diesel electric generator. The relationship between performances and structure parameters of mufflers are analyzed, the equations of noise reduction are derived, the factors of influencing muffler performances are obtained, and the selecting rules of them are established. The experimental research for the acoustic and aerodynamic performances of muffler proved the theoretical results in consistency with the experimental one. Furthermore, the experiments show that the resistance-loss is caused mainly by the partial resistance-loss in expansion chamber. The designed muffler combined with jet and impedance has good acoustic and aerodynamic performances, its amount of noise reduction is 40 dB. The resistance-loss of the muffler is smaller and less than 51 Pa at velocity 8 m/s of airflow. The proposed rules of structural parameter selection have their meaningful references for designing and improving muffler in engineering application.