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Focus on the three giants, learn more about fan knowledge

Teach you how to distinguish between noise and noise of a cooling fan

Back to list Release date: Sep 06, 2018

        It is normal for an industrial cooling fan to make noise more or less with its service life. However, many people mistakenly think these noises are abnormal noises and think that there seems to be something wrong with the cooling fan. In fact, noise is not equal to abnormal sound, which is a normal phenomenon.

What is the noise of the cooling fan?

        The noise of the cooling fan is caused by the blades of the cooling fan being periodically subjected to the pulse force of the uneven air flow at the outlet, for example, the uneven distribution of pressure on the blades themselves and the blades, and the disturbance to the surrounding gas and parts during rotation also constitute rotational noise. In addition, there is vortex noise caused by the pressure distribution pulsation on the blade due to the turbulent boundary layer, vortex and vortex separation caused by the tearing of the gas flowing through the blade. Generally speaking, the noise of the cooling fan is closely related to the movement of its blades and belongs to physical noise.

          For the same series of cooling fan fans, the greater the air volume and pressure, the greater the noise. Therefore, we should choose the fan form reasonably according to the actual situation, because excessive margin will not only waste electric energy, but also increase noise, which is harmful to us. For the same type of cooling fan, the fan running at low speed should be selected as far as possible. For different types of fans, the one with lower noise should be selected, not just the rotation speed.

How did the noise of the cooling fan come into being?

        The noise of the cooling fan is different from that of the noise.The noise sounds only like the wind, but the noise, besides the wind, is emitted by other sounds ( with more than two kinds of sounds ). The abnormal sound may be caused by foreign objects or deformation in the bearing, collision due to improper assembly, or non-uniform winding of motor windings, resulting in looseness.

        We usually use the method of close to the ear to detect the abnormal sound, which is subjective and difficult to identify and controversial.If the number of fans used is large, the abnormal sound can be identified by means of spectrum analysis equipment, and the noise spectrum energy distribution can be identified.

          At present, industrial cooling fans are widely used for cooling equipment, removing dust and maintaining air circulation in workshops, so it is necessary to know how to distinguish noise from noise in cooling fans.


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