The speed of the cooling fan refers to the number of times the fan blade rotates per minute, and the unit is RPM. Rotational speed measuring instrument refers to the measuring tool for measuring the speed of an object, and a digital display measuring instrument is generally used.
The working principle of the cooling fan. When the cooling fan works, the first step is to convert electrical energy into mechanical energy. The principle is first: when power is supplied to the cooling fan, the fan coil has current. According to the right-hand rule of ampere, we know that a magnetic field will occur around the coil, and a rubber magnet filled with magnetism is attached to the inside of the cooling fan blade. The magnetic field generated by the conductor generates repulsive force with the fixed magnetic field. When the repulsive force is greater than the static friction force of the fan (the friction force of the fan bearing, the wind resistance of the fan blade rolling), the fan blade of the fan naturally rolls. The power supply voltage of the DC fan is fixed, and a Hall sensor component must be used as a synchronous detection device to control a set of circuits so that the two sets of coils around the axis can be operated in turn to generate different magnetic fields.
Through the operation principle of the electric fan, we know that the primary decision condition of the fan speed is the structure and parts of the electric fan, the friction of the bearing and the wind resistance of the inclination angle of the fan blade, etc., of course, there are external factors. Let's analyze it below: Air cooling realizes heat dissipation. The primary factor that affects air cooling heat dissipation is the environmental structure of the heat dissipation system. When the system environment is relatively sealed, the wind pressure of the fan should be considered when selecting the heat dissipation fan. If the fan pressure is not enough, the fan speed will be obvious. The air volume drops significantly, and the heat dissipation effect is not achieved. Therefore, the external wind pressure is a factor that affects the speed of the fan (supercharged cooling fans can overcome); there is also a more significant factor is the external environment, such as In environments such as sandy, greasy, high and low temperatures, if the general cooling fan is not protected, the harsh environment will also have a significant impact on its speed.
