The principle of noise reduction in diesel generator room is to ensure the ventilation condition of diesel generator without reducing the output power, adopt efficient sound absorbing materials and noise reduction device to noise reduction in the inlet and outlet air passages and exhaust system, so that the a-level noise emission reaches the national standard (85dB).
1. Start from the sound source
The most fundamental method of generator noise reduction is to start from sound source and adopt some conventional techniques to reduce noise.Such as muffler, sound insulation, sound absorption, vibration, such as the most effective way.
(1) reduce exhaust noise.Exhaust noise is the main noise source of the unit, which is characterized by high noise level, fast exhaust speed and great difficulty in controlling.The exhaust A sound level noise is generally reduced by 40~60dB by using A specially designed impedance compound muffler.
(2) reduce the noise of axial fan.When reducing the noise of generator cooling fan, two problems must be considered.The second is the required amount of silencing.For the above two points, the resistive plate muffler can be selected.
2. Environmental transformation of the machine room
(1) Sound insulation in machine room.
After reducing the exhaust noise and cooling fan noise of the unit, the main noise sources left are the engine mechanical noise and combustion noise. The method adopted is to remove all the Windows except the necessary inner wall observation window connected with the observation room. All the holes and holes should be sealed tightly and the sound insulation of the brick wall should be more than 40dB. Machine room doors and Windows are fireproof and soundproof.
(2) Air inlet and exhaust
The problem of ventilation and heat dissipation should be solved after the room sound insulation treatment. The air inlet shall be arranged in the same line as the generator set and the air outlet. The air inlet shall be equipped with resistance blade muffler. As the pressure loss of the air inlet is within the allowable range, the air flow in and out of the machine room can be naturally balanced and the ventilation and heat dissipation effect is obvious.
(3) sound absorption processing.
The five walls in the machine room can be used for sound absorption processing except the ground.
(4) Vibration isolation of the unit.
Vibration isolation of the unit.Before the installation of generating sets, the vibration isolation treatment should be carried out strictly according to the relevant data provided by the manufacturer to avoid long-distance transmission of structural sound. The vibration of the ground near the generator set must be measured. If the sense of vibration is obvious, the generator set should be isolated first.
After reducing noise effectively, the machine room environment is more beautiful and practical. Usually the sound absorption layer of metope and condole top is decorated with micro hole aluminium model punching plate outside, at the same time reasonable configuration illume system. So the noise of machine room is reduced more effectively and the good effect of noise reduction is achieved.