With the progress of the times, the development of science, and the popularization of air purifiers, more and more manufacturers are worried about how to "radiate heat". This is a topic everyone is thinking about. In addition to the heat transfer requirements, noise is also one of the important choices in the use of products, and people do not want to buy a noisy fan.

It is very difficult for the cooling fan to be responsible for heat dissipation and not to produce annoying noise. Therefore, the speed of the cooling fan and the generation of noise must be taken into account when using the fan, which is a headache for designers. The higher the speed of the fan, the higher the flow rate and static pressure, and the relative noise. However, the speed is insufficient and it cannot provide enough air volume and static pressure to take away the heat. In this case, the variable number fan came into being.

When a large amount of heat needs to be taken away, the speed is high, and when a large amount of heat does not need to be taken away, it can be operated at a low speed. When the product generates a lot of heat, it needs high-speed air volume and pressure to take away the heat, and of course the noise is also loud; when the cooling fan does not need to run at a high speed, the speed can be reduced to reduce noise.