Analysis and treatment of noise source of Roots blower

Roots blower contains a variety of noise sources, and its radiation noise, most of which are air inlets and outlets, radiated atmospheric dynamic noise, radiation from the casing, motors, bearings, etc., mechanical noise, and solid sound radiated by the vibration of the foundation. Among these parts of noise, the atmospheric dynamic noise radiated from the inlet and outlet is referred to as aerodynamic noise, which is the main one here, Others, such as machine noise and electromagnetic noise, are secondary during normal operation of Roots blower.

According to the spectrum analysis of the noise generated by Roots blower, it is characterized by low-frequency broadband. The aerodynamic noise of Roots blower consists of two parts, namely, the muffler of torsional noise and vortex noise.

In general, the air inlet and exhaust port of the fan, the dynamic property of the radiated atmosphere, and the noise are higher than the noise radiated from other parts in decibels. Therefore, appropriate silencers should be used on the air inlet and exhaust pipes first. Nowadays, both at home and abroad tend to adopt dissipative silencers, while silencers with large volume and narrow silencing channel are rarely used. Of course, the choice, plan and device of silencers should be based on the actual situation.

The method of sound insulation cover shall be adopted for the establishment of sound insulation cover. Most of its skills are the adoption of key cooling forms, and how to ensure the normal operation of Roots blower. Nowadays, air cooling methods are widely adopted at home and abroad, including self fan ventilation cooling method, negative pressure suction cooling method, air circulation ventilation cooling method inside the hood, and additional machine ventilation cooling method to transform the fan room. If the fan unit has a special fan room, the existing fan room can be transformed into a sound insulation room according to the site conditions, that is, the fan can be closed in the fan room so that its noise cannot be transmitted. Most of the techniques are to use sound insulation doors, sound insulation windows, sound insulation screens and walls for sound insulation, and use appropriate sound absorption data and other pipes to wrap up, In order to reduce the noise radiated from the Roots blower duct, the duct can be banded to cut off the road where the noise spreads. The basic way for Roots blower to reduce the noise is to try to reduce the impulse noise. The control method is to try to prevent and reduce the noise radiation generated by the noise source. The noise control method is not only strengthened, but also lost due to the pressure of the muffler, The result is the loss of energy, which is very bad for saving energy.