Guidelines to reduce fans’ noise.

The following seven guidelines provide users the best way to reduce fans to a minimum noise:

1.SystemImpedance

An enclosure between the inlet and outlet of the total system impedance range of 60-80%, while the greater airflow, noise is relatively higher. System impedance higher, the greater the airflow required for cooling, so to minimize the noise, the system impedance must be reduced to a minimum.

2.Airflow disrupt

Along the flow path caused by obstacles encountered spoiler will generate noise. Therefore any hindrance, especially in the critical range of the air inlet and outlet must be avoided in order to reduce noise

3.Fan speed and size

Because of the high speed fans have a greater than the low speed fan noise, it should be possible, try and use low speed fans. And a large size, low speed fan, usually higher than small size, high speed fan, the same air volume in the conveying quiet.

4.Higher Temperature

In one fan system, the cooling air volume required is inversely proportional to the allowed temperature rise. Allow slightly increased temperature, to a significant reduction in the required amount of wind. Therefore, if the restrictions imposed on the allowable temperature rise slightly relax some of the required air volume will be reduced, the noise can be reduced.

5.Vibration for cooling fan

Some times, the entire system is very light weight, or the system must operate in accordance with certain provisions, especially when soft isolated equipment is recommended in order to avoid the fan vibration transmission.

6.Voltage fluctuation

Voltage changes will affect the noise level. The higher the voltage applied to the fan, as speed increases, the greater the vibration, the larger the noise generated.

7.Cooling fan Design

Design for each fan constitute part, will affect the noise level. The following design considerations noise reduction can be accomplished: winding core size, blades and frame design and precision manufacturing and balance.