When the wind noise "Waterproof Cooling Fan" work, due to leaf veins are periodically subjected to dynamic role of export uneven airflow, noise; on the other hand, due to the uneven distribution of the blade itself and the blade pressure, "Waterproof Cooling Fan" rotation when the surrounding gas and also constitute part of the rotational noise disturbance; moreover due to the turbulence generated when the gas flows through the blade attachment level, vortex and vortex detachment, causing pulsating pressure distribution on the blade and vortex noise. This noise can cause, comprehensive called "cut wind noise", generally a large amount of wind pressure fan, "Waterproof Cooling Fan" cut wind noise as well.