Self Brilling Anchor Bar,Self Drilling Anchor Bar,Self-Drilling Anchor,Self Drilling Anchor Bar Connection TIANJIN YOUFA STEEL CO., LTD , https://www.cnyoufasteel.com
Perkins centrifugal pump generator set has noise noise reduction treatment
The main noise sources of diesel generator sets are diesel engines, including exhaust noise, mechanical noise and combustion noise, cooling fan and exhaust noise, air intake noise, generator noise, noise generated by ground vibration, etc.:
1. Exhaust noise. Exhaust noise is a kind of high-temperature, high-speed pulsating airflow noise, which is the most energy of engine noise. Its noise can reach more than 100 db, which is the most important component of total engine noise. The exhaust noise generated by the generator is directly discharged through the simple exhaust pipe (the original exhaust pipe of the generator set), and the noise frequency is also significantly increased as the airflow speed increases, which has a serious impact on the life and work of neighboring residents.
2. Mechanical noise and combustion noise. Mechanical noise is mainly caused by vibration or mutual impact caused by periodic changes in gas pressure and motion inertia during operation of various moving parts of the engine. It has the characteristics of far-reaching noise and reduced attenuation. Combustion noise is the structural vibration and noise generated by diesel during combustion.
3. Cooling fan and exhaust noise. Unit fan noise is composed of eddy current noise, rotational noise, and mechanical noise. Exhaust noise, airflow noise, fan noise, and mechanical noise will propagate through the exhaust ducts, causing noise pollution to the environment.
4, the wind noise. The function of the air inlet passage is to ensure the normal operation of the engine and to create good heat dissipation conditions for the unit itself. The air inlet passage of the unit must be able to smoothly enter the engine room, but at the same time, the mechanical noise and airflow noise of the unit will be radiated to the outside of the machine room through this air inlet channel.
5. Transmission noise of ground vibration. The strong mechanical vibration of the diesel engine can be transmitted to the outside through the ground and then radiated through the ground.
The principle of noise reduction treatment of diesel generator room is to use the high-efficiency sound absorbing material and noise reduction and muffling device to reduce the noise of the intake and exhaust passages and the exhaust system under the premise of ensuring the ventilation condition of the diesel generator set without reducing the output power. Make the noise emission meet the national standard (85db(a)).
The most fundamental way to reduce noise from generators is to start with the sound source and use some conventional noise reduction techniques; such as muffler, sound insulation, sound absorption, vibration isolation, etc. are the most effective methods.
1. Reduce exhaust noise. Exhaust noise is the main noise source of the unit. It is characterized by high noise level, fast exhaust speed and difficult treatment. The use of a special impedance-type compound muffler generally reduces exhaust noise by 40-60 db (a).
2. Reduce the noise of the axial fan. When reducing the noise of the genset cooling fan, two problems must be considered. One is the pressure loss allowed by the exhaust passage. The second is the amount of noise required. For the above two points, a resistive chip muffler can be selected.
3. Sound insulation, sound absorption treatment and unit vibration isolation of the equipment room
(1), the sound insulation of the computer room. After the unit's exhaust noise and cooling fan noise are reduced, the main source of noise remaining is diesel mechanical noise and combustion noise. The method adopted is that except for the inner wall observation window connected to the observation room, the other windows are removed, and all the holes and holes are densely sealed. The sound insulation of the brick wall requires 40 db (a) or more. The doors and windows of the machine room are equipped with fireproof soundproof doors and windows.
(2), air intake and exhaust. After the sound insulation of the equipment room, it is necessary to solve the problem of ventilation and heat dissipation in the equipment room. The air inlet should be placed on the same line as the generator set and exhaust vent. The air inlet should be equipped with a resistive chip muffler. Since the pressure loss of the air inlet is also within the allowable range, the air volume in the engine room can be naturally balanced, and the ventilation and heat dissipation effect is obvious.
(3), sound absorption treatment. The five walls in the machine room except the ground can be used for sound absorption treatment, and the perforated plate resonance sound absorption structure is adopted according to the spectrum characteristics of the generator set.
(4) The exchange of indoor air and the good sound insulation of the equipment room will make the air in the machine room not be convected when the closed water-cooled generator set is shut down, and the high temperature in the room cannot be lowered in time. The low-noise axial flow fan can be used. And with a resistive chip muffler can solve the problem.
(5), unit vibration isolation. Before the generator set is installed, the vibration isolation treatment should be carried out strictly according to the relevant information provided by the manufacturer to avoid the long-distance propagation of the structural sound, and the air sound is constantly radiated during the propagation, and the noise level of the boundary of the plant cannot be achieved. For existing generator sets that require treatment due to exceeding the standard, the vibration of the ground near the unit must be measured. If the vibration is obvious, the generator set must be subjected to vibration isolation.