Everyone who knows about cooling fans is not unfamiliar, and they are often used in daily life. However, most users are familiar with the technical indicators of cooling fans, and they don’t pay much attention when purchasing cooling fans. It can be seen from the technical indicators that the heat dissipation effect of the cooling fan, consumers can understand before purchasing. So what are the technical indicators of the cooling fan? Air volume Air volume refers to the total volume of air discharged or classified by the cooling fan per minute. The air volume is the most important indicator to weigh the heat dissipation capacity of the cooling fan. Generally speaking, the greater the air volume, the higher the heat dissipation capability. Wind pressure Wind pressure refers to the pressure encountered when the cooling fan is running. Wind pressure and breeze volume are two relative concepts. Generally, if the air volume of the cooling fan is large, the air pressure is small. On the contrary, the air volume of the cooling fan is small, and the air pressure is large. When the rotor of the vibration cooling fan rotates, the physical center of mass of the rotor and the center of inertia of the rotating shaft are not on the same axis, which will cause the imbalance of the rotor. When the rotor rotates, the centripetal force generates a force on the shaft support to form vibration, and the vibration is transmitted to all parts of the machine through the basic path. Wind noise cooling 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). The noise of the cooling fan is related to friction and air movement. The higher the fan speed and the greater the air volume, the greater the noise generated. The abnormal sound of the cooling fan wind noise is different from the noise. When the fan is running, there are other sounds besides the wind, and these sounds are abnormal sounds. Abnormal noise may be caused by foreign matter or deformation in the bearing, collision due to improper assembly, or uneven winding of the motor winding, which may cause abnormal noise.