This article mainly explains to the user how the noise generated by the diesel generator set is generated. Today, more and more companies are starting to use the generator set as a standby power source in their daily production work, but their noise has brought health to people. The troubles in work and life can only be better when the noise generated by the generator is understood.     The main cause of noise is related to its working principle. The noise mainly produced by different parts mainly includes the following parts:
1. Mechanical noise:
Mechanical noise is mainly caused by the vibration or impact caused by the periodic changes of the gas pressure and the movement inertial force during the operation of various moving parts of the engine. Among them, the following are serious: the noise of the piston crank linkage mechanism, The noise of the valve train, the noise of the transmission gear, the mechanical vibration and noise caused by the unbalanced inertial force. The strong mechanical vibration of the diesel generator sets can be propagated to the outside of the ground from a long distance through the foundation, and then the noise can be formed through the radiation of the ground. This structural noise propagates far and decays, and it is difficult to isolate once formed.
2. Burning noise:
Combustion noise is the structural vibration and noise produced by diesel during combustion. The sound pressure level of the combustion noise in the cylinder is very high, but most of the parts in the engine structure have higher rigidity and the natural frequencies are mostly in the high-middle frequency range due to the mismatch of acoustic wave propagation frequency response because of the low frequency band. High peak cylinder pressure levels do not propagate smoothly, while cylinder pressure levels in the mid-to-high frequency range are relatively easy to transmit.
3. Exhaust noise:
Exhaust noise is a kind of high-temperature, high-speed pulsating airflow noise. It is a part of the engine noise with large energy and many components. It is much higher than the intake noise and mechanical noise emitted by the body and is the main component of the total engine noise. Its fundamental frequency is the firing frequency of the engine. The main components of exhaust noise include the following: low-frequency pulsation noise caused by periodic exhaust smoke, air column resonance noise in exhaust pipes, Helmholtz resonance noise of cylinders, high-speed airflow through valve clearance, and tortuous pipelines. The generated noise, eddy current noise, and regenerative noise generated by the exhaust system under the excitation of the pressure wave in the pipeline, with the increase of the airflow speed, the noise frequency is significantly improved.
4. Inlet noise:
When the diesel generator sets are in normal operation, they need sufficient fresh air supply to ensure the normal operation of the engine on the one hand, and on the other hand to create good heat dissipation conditions for the units, otherwise the unit cannot guarantee its performance. The air intake system of the unit basically includes the air intake channel and the air intake system of the engine itself. The air intake channel of the unit must enable the fresh air to smoothly enter the equipment room. At the same time, mechanical noise and airflow noise of the unit can also be radiated to the equipment room through the air intake channel. outside.
5. Generator noise:

Generator noise includes electromagnetic noise due to magnetic field pulsation between the stator and the rotor, and mechanical noise generated by the rotation of the rolling bearing.
6. Cooling fan and exhaust noise:
The unit fan noise consists of vortex noise and rotational noise. The rotation noise is caused by periodic disturbances caused by the cutting air flow of the fan blades; the vortex noise is generated when the airflow is separated on the rotating blade section due to the viscosity of the gas. Vortex flow, radiating a non-steady flow noise. Exhaust noise, air flow noise, fan noise, and mechanical noise all radiate through the exhaust passage.
After understanding the basic knowledge of diesel generating set noise, we can choose suitable silencing engineering to reduce noise and achieve a harmonious production environment.