Source 24V DC Cooling Fan noise

"24V DC Cooling Fan" workaround noise. We know there are a lot of electronic products will have noise generation, especially for industrial equipment, many will have. Noise is a sound harmful to our health, which we have to solve the problem. But POOKIN far, has not completely eliminate the noise method. "24V DC Cooling Fan" noise is how come, six proportional to the total noise level of the fan blade speed square. According to the analysis, fan noise source is basically a dipole nature. Further to the introduction of noise is due to the blades acting on the blower air flow through the veins caused by force. Can be considered "24V DC Cooling Fan" fans discrete frequency noise source has two, one is with the pressure field caused by the movement of the rotor blade propeller noise, the other is the leaf veins aerodynamic interference caused by power noise. Wind maneuver, quiet distance between the blades is an important factor interference noise.