1. System impedance
The range between the air inlet and outlet of an enclosure accounts for 60% to 80% of the total system impedance. In addition, the greater the gas flow, the higher the noise. The higher the system impedance, the greater the gas flow required for heat dissipation. Therefore, in order to minimize noise, the system impedance must be minimized.
2. Gas flow disturbance
Turbulence caused by obstructions encountered along the gas flow path can cause noise. Therefore, any obstacles, especially in the critical air inlet and outlet areas, must be avoided to reduce noise.
3. Fan speed and dimensions
Since high-speed fans cause more noise than low-speed fans, you should try and choose low-speed fans as much as possible. A fan with a larger size and lower speed is usually quieter than a fan with a lower size and higher speed when delivering the same air volume.
4. Temperature increase
In a system, the air volume required for heat dissipation is inversely proportional to the allowable temperature rise. Allowing a slight increase in temperature rise can greatly reduce the required air volume. Therefore, if the restrictions imposed on the allowable temperature rise are slightly relaxed, the required air volume will be reduced and the noise will also be reduced.
5. vibration
In some cases, when the weight of the entire system is very light, or the system must be operated in a certain manner, it is especially recommended to use soft insulation equipment to avoid the transmission of fan vibration.
6. Voltage fluctuation
Voltage fluctuations will affect the noise level. The higher the voltage applied to the fan, the higher the rotation speed, the greater the vibration and the greater the noise caused.
7. Design considerations
The design concept of each part of the fan will affect the noise level. The following design concepts can be considered to reduce noise: the external dimensions of the winding core, the design concepts of the fan blades and the outer frame, and the precise manufacturing and balance.
