Noise reduction measures usually taken in power generator rooms

Diesel generator sets usually produce 95~128 dB (a) noise when running. If the necessary noise reduction measures are not taken, the noise caused by the operation of the unit will cause serious damage to the surrounding environment. In order to protect and improve the quality of the environment, the noise must be controlled.

From the main noise source of diesel generator for diesel engine, including exhaust noise, mechanical noise and combustion noise, cooling fan and transfers the generated noise of exhaust noise, wind noise, noise, ground vibration generator:

1. Exhaust noise. Exhaust noise is a high temperature and high speed pulsating airflow noise. It is the largest energy in engine noise. Its noise is over 100dB. It is the most important component of engine total noise.

2 、 mechanical noise and combustion noise. The mechanical noise is mainly caused by the vibration or mutual shock caused by the periodic change of the gas pressure and the inertia force of the moving parts of the engine during the operation. It has the characteristics of noise propagation, attenuation and attenuation. Combustion noise is the structural vibration and noise produced by combustion of diesel fuel.

3 cooling fan and exhaust noise. Fan noise is composed of swirl noise, rotating noise and mechanical noise. The exhaust noise, air flow noise, fan noise and mechanical noise will be transmitted through the exhaust air passage, thus causing noise pollution to the environment.

4. Inlet noise. The function of the air inlet is to ensure the normal operation of the engine and to create a good cooling condition for the generator itself. The inlet air passage of the unit must be able to make the air flow smoothly into the engine room, but at the same time, the mechanical noise and air flow noise of the unit will be radiated outside the engine room through the air inlet.

5, the transmission noise of ground vibration. The strong mechanical vibration of the diesel engine can be transmitted over the ground over a long distance to the outside and then radiated by the ground.

The principle of noise reduction is to ensure the ventilation conditions of the diesel generator set, that is, the use of efficient sound-absorbing materials and noise reduction and noise elimination devices on the premise that the output power is not reduced

The noise of the intake and exhaust passages and the exhaust system is reduced so that the noise emission reaches the national standard (85dB (A)).

The most fundamental way to reduce noise is to start from the sound source and adopt some conventional techniques to reduce noise. Such as muffler, sound insulation, sound absorption and vibration isolation are the most effective methods.

1, reduce exhaust noise. Exhaust noise is the most important noise source of the unit, which is characterized by high noise level, high exhaust speed and difficult to control. The use of a specially made impedance type composite muffler generally reduces exhaust noise by 40-60 dB (a).

2, reduce axial fan noise. When reducing the noise of the generator fan, two problems must be considered, one is the pressure loss caused by the exhaust passage. The two is the required noise reduction. In view of the above two points, a dissipative silencer can be used.

After the effective noise reduction, in order to make the room environment more beautiful and practical, usually the wall and ceiling sound absorption layer is also decorated with microporous aluminum-plastic punching plate, at the same time reasonable lighting system.