Noise source of cooling fan


The factors that cause the noise of the cooling fan and […]

The factors that cause the noise of the cooling fan and the reasons that affect the noise of the fan;

1. The impedance of the cooling fan system: the range between the air inlet and the air outlet of a chassis accounts for 60% to 80% of the total system impedance. In addition, the greater the airflow, the higher the noise. The higher the system impedance, the greater the airflow required for cooling, so in order to minimize noise, the system impedance needs to be reduced.

2. Airflow disturbance of the cooling fan: The turbulence caused by the obstacles encountered along the airflow path will produce noise. Therefore, any obstacles, especially in the critical air inlet and outlet areas, must be avoided to reduce noise.

3. Speed and size of the cooling fan: Since high-speed fans produce greater noise than low-speed fans, low-speed fans should be tried and used as much as possible. A fan with a larger size and a lower speed is usually quieter than a fan with a small size and a higher speed when delivering the same air volume.

4. Voltage variation of cooling fan: Voltage variation will affect the noise level. The higher the voltage applied to the fan, the greater the vibration and the greater the noise due to the increase in speed. Design considerations will affect the noise level of each part of the fan. The following design considerations can achieve noise reduction: the size of the winding core, the design of the fan blade and the outer frame, and the precise manufacturing and balance.