The main noise sources of Perkins diesel generator set are generated by diesel engine, including exhaust noise, mechanical noise and combustion noise, cooling fan and exhaust noise, air inlet noise, generator noise, noise generated by transmission of foundation vibration, etc. 1.Exhaust noise. Exhaust noise is a kind of high-temperature and high-speed pulsating air flow noise, which is one of the most energetic engine noise. Its noise can reach more than 100 dB, and it is the main part of the total engine noise. When the Perkins generator works, the exhaust noise is directly discharged through the simple exhaust pipe (the original exhaust pipe of the generator set), and with the increase of air flow speed, the noise frequency is also significantly increased, which has a serious impact on the life and work of the neighboring residents. 2.Mechanical noise and combustion noise. Mechanical noise is mainly produced by the vibration or mutual impact caused by the periodic ch...