Why does AC fan produce noise?

AC fans are widely used in daily life and are very common mechanical equipment. Everyone will find in life that the AC fan will make a certain noise when it is running, and its sound will cause trouble to some extent.

So why does AC fan produce noise? In fact, in addition to the heat dissipation effect, the working noise of the fan is also a common concern. Fan noise is the size of the noise generated by the fan when it is working, which is affected by many factors, and the unit is decibel (dB). When measuring the noise of the fan, it needs to be carried out in an anechoic room with a noise of less than 17dB, one meter away from the fan, and aligned with the fan's air inlet along the direction of the fan's shaft, using a weighted method for measurement. The spectral characteristics of fan noise are also very important, so it is also necessary to record the frequency distribution of fan noise with a spectrum analyzer. Generally, the fan noise is required to be as small as possible and there should be no abnormal noise.

　　Fan noise is related to friction and air flow. The faster the rotation speed of the AC fan, the greater the air volume, so the noise will be greater, and the vibration of the AC fan itself is also a certain factor. The high-quality fan will have less vibration but the noise Difficult to overcome. To solve this problem, we can try to use a larger fan. When the air volume is the same, the operating noise of a large fan at a lower speed should be smaller than that of a small fan at a high speed. Another factor that we easily overlook is the bearing of the fan. As the fan rotates at a high speed, there is friction and collision between the shaft and the bearing, so it is also a major source of fan noise.

　　With the changes in usage and environment, some require fans with different speeds to meet the needs. Some manufacturers deliberately design AC fans with adjustable fan speeds, and can customize their own needs, divided into manual and automatic. The main purpose of manual is to allow users to use low speed in winter to get low noise, and use high speed in summer to get good heat dissipation effect. Automatic temperature control radiators generally have a temperature control sensor, which can automatically control the fan speed according to the current working temperature. If the temperature is high, the speed will be increased, and if the temperature is low, the speed will be reduced, so as to achieve a dynamic balance, thereby allowing wind noise. Maintain an optimal combination with the heat dissipation effect.

To sum up, in fact, AC fans will produce noise more or less, because during the operation of AC fans, the friction of the bearing will make noise, and the friction between the fan wheel and the air will also make noise. However, if the noise emitted by the AC fan is too loud, it is necessary to consider whether the performance of the AC fan is not good, so that corresponding measures can be taken.

Shenzhen Ruiapple Electronics Co., Ltd. is a professional fan manufacturer with 20 years of R&D, production and sales experience. Main business: cooling fan, DC fan, AC fan, silent fan, centrifugal fan, blower and other full range of heat dissipation and ventilation products as an integrity enterprise, the series of cooling fan products have obtained UL, CUL, CE, CCC, ROHS, etc. International Certification.

Shenzhen Ruiapple Electronics Co., Ltd. was established in 2000. For 20 years, it has focused on R&D, manufacturing, and sales of DC AXIAL FAN, AC AXIAL FAN, CENTRIFUGAL FAN, and blower ( BLOWER), AC to DC fan (EC FAN), DC motor (DC MOTOR), AC to DC (EC MOTOR) motor and other full series of cooling and ventilation products as a whole series of integrity enterprises.