How to distinguish the noise and abnormal sound in the cooling fan?

In general, heat dissipation fans are used in industrial production. They are widely used for heat dissipation, dust removal and air circulation in workshops. So once the noise and murmur of the heat dissipation fan appear, it will not only affect the performance of the heat dissipation fan, but also make the people who work irritable. Last time, I shared with you how to improve the quality of heat dissipation fans from the root. Today, I'm coming to DeNuoSen Technologist to introduce how to distinguish noise and murmur in heat dissipation fans.

The difference between noise and abnormal sound in the cooling fan is:

1, cooling fan noise:

Noise of cooling fan is caused by periodic pulsation of non-uniform airflow at the outlet of the blade; for example, the non-uniform distribution of pressure on the blade itself and on the blade, the disturbance of surrounding gas and parts when rotating also constitutes rotating noise; and the swirling layer, vortices and vortices produced by the tearing of the airflow through the blade. Vortex shedding causes vortex noise generated by the pulsation of pressure distribution on the blade.

For the same series of fans, the noise is bigger when the air volume and pressure are large. Therefore, to choose the fan form reasonably according to the actual situation, excessive surplus not only wastes electric energy, but also increases noise, which is harmful or not for us. For the same type of fan, low speed fan should be selected as far as possible; for different types of fan, low noise should be selected, not only speed.

2. The abnormal sound of the radiator fan:

Different from the noise, the noise of the cooling fan only sounds like pure wind, while the noise, in addition to wind, there are other sounds (with more than two sounds). The abnormal sound may be caused by foreign body or deformation in the bearing, collision due to improper assembly, or uneven winding of the motor, resulting in loosening.

Generally, the method of detecting abnormal sounds is close to the ear. Subjective factors are larger, and it is difficult to identify. It is easy to dispute. If the number of fans used is large, the abnormal sounds can be identified by means of spectrum analysis equipment. The spectrum energy distribution of noise can be used to identify abnormal sounds.