Noise Generation and Treatment of Air Cooled Refrigerating Unit

During the operation of refrigeration unit, it is easy to produce noise due to improper operation and installation. Generally speaking, the reasons for the noise of the fan of the water chiller are as follows:

The blade of the fan of the refrigeration unit will rub with the air when it rotates. The frequency of noise is composed of multiple frequencies, which are related to the speed of the fan. It is suggested that if the axial-flow fan has the configuration of moving wing and stationary wing, the number of blades of both should be different to avoid greater noise resonance.

Because of the vortex generated by the blade, it will also produce noise. During the operation of the fan, the vortex will be generated on the back of the moving wing, which will not only reduce the efficiency of the fan, but also produce noise. In order to reduce this phenomenon, the installation angle of the fan blade should not be too large, and the bending of the fan blade should be smooth, and the sudden change should not be too large.

The air duct resonates with the shell to produce noise. The joint between the air duct and the inner surface of the fan shell shall be smooth to avoid rough and uneven, which may cause tearing sound. In the design, sometimes the air duct can be covered with anti sound material to reduce noise.

In addition, in addition to the fixed noise of the fan itself, there are many noise sources. Such as: bearing due to insufficient precision, improper assembly or poor maintenance will cause abnormal noise. The motor also produces noise, some of which are caused by poor design or poor manufacturing quality control, but sometimes by the cooling fans inside and outside the motor. Therefore, in the selection of equipment, we must strictly carry out the screening of regular products, and consider the humanized design of equipment and other factors.