The aerodynamic noise of the motor is caused by the flo […]
The aerodynamic noise of the motor is caused by the flow and change of the rotating rotor and the cooling fan rotating with the shaft. It increases with the increase of the speed of the fan and the rotor. The faster and the more the flow, the more the noise Large aerodynamic noise and speed, fan and rotor shape, roughness, unbalance, air duct cross-section changes, air duct shape and so on.
The main measures to reduce aerodynamic noise are:
1 The connection between the outer fan and the rotating shaft is not connected by a key, but the knurling straight line process is adopted; the outer fan needs to be uniform in thickness, no distortion, uniform spacing, and balanced in calibration;
2 Eliminate the fan for the motor with good heat dissipation or low temperature rise to eliminate the noise source; for the external fan, no ventilation allowance should be left in the design, and the axial flow fan is preferred;
3 The surface of the rotor should be as smooth as possible;
4 obstacles should be reduced in the air duct, and streamlined air ducts should be used for special air ducts. The cross section of the air duct should not suddenly change;