Ways to eliminate noise from diesel generators

When the diesel generator set is running, it will usually produce 95-110db(a) noise. The noise of the diesel generator set during operation will cause serious damage to the surrounding environment. So when the noise source cannot be reduced, what measures should be adopted to control the noise of diesel generator sets?

1. Noise source analysis of diesel generator set

Diesel engine noise is a complex sound source composed of multiple sound sources. According to the way of noise radiation, it can be divided into aerodynamic noise, surface radiation noise and electromagnetic noise. According to the causes, the surface radiation noise of diesel generator sets can be divided into combustion noise and mechanical noise. Among them, aerodynamic noise is the main noise source of diesel engine group noise.

1. Aerodynamic noise is due to the unstable process of gas, that is, the noise of diesel generator set caused by gas disturbance and the interaction of gas and object. Aerodynamic noise directly radiated to the atmosphere, including air intake noise, exhaust noise and cooling fan noise.

2. Electromagnetic noise is the diesel engine noise generated by the generator rotor rotating at high speed in the electromagnetic field.

3. Combustion noise and mechanical noise are difficult to distinguish strictly. Generally, the pressure fluctuation formed by combustion in the cylinder of diesel generator set is called combustion noise. The noise of diesel engine set radiating through the cylinder head, piston, Lianxuan, crankshaft, and body . The diesel engine block noise produced by the impact of the piston on the cylinder liner and the mechanical impact and vibration of the moving parts is called mechanical noise. Generally, direct injection diesel engine combustion noise is higher than mechanical noise? Non-direct injection diesel engine mechanical noise is higher than combustion noise. However, the combustion noise is higher than the mechanical noise during low-speed operation.

2. Noise control measures of diesel generator sets

The noise control measure of diesel generator set 1: soundproof room.

Install a sound insulation room at the position of the diesel generator set, the size is 8.0m×3.0m×3.5m, and the outer wall of the sound insulation board is 1.2mm galvanized sheet. The inner wall is a 0.8mm perforated plate, the middle filling is 32kg/m3 ultra-fine glass wool, and the concave surface of the channel steel is filled with glass wool.

The second noise control measure for diesel generator sets: exhaust air noise reduction.

The diesel generator set relies on its own fan to exhaust the air. Install an AES rectangular muffler at the front of the exhaust room. The size of the muffler is 1.2m×1.1m×0.9m. The muffler is equipped with a muffler sheet thickness of 200mm and a spacing of 100mm. The silencer sheet adopts ultra-fine glass wool structure with galvanized perforated plates on both sides. 9 mufflers of the same size are assembled into one. Large muffler of 1.2m×3.3m×2.7m. Exhaust shutters of the same size are located 300mm in front of the muffler.

The third measure to control the noise of diesel generator sets: muffle the air intake.

Install a natural inlet muffler on the top of the sound insulation room. The muffler is made of the same exhaust muffler, the net muffler length is 1.0m, the cross-sectional size is 3.4m×2.0m, the muffler thickness is 200mm, the spacing is 200mm, the muffler is connected to an unlined 90° muffler elbow, the muffler elbow length is 1.2 m.

The fourth noise control measure for diesel generator sets: exhaust smoke and silence.

The noise is muffled by the original two residential mufflers of the diesel generator set. The muffled flue gas is combined into a Φ450mm flue pipe and discharged upward from the exhaust shutters.