As we all know, large industrial fans are widely used in industrial plants, logistics warehouses, waiting rooms, exhibition halls, gymnasiums, supermarkets and other large spaces because of their "power saving, large coverage and no space occupation". As the only common industrial cooling machine for ventilation and personnel cooling in large spaces, what is the noise?

1. Wind noise

When large industrial fans work, the blades periodically bear the pulsating force of uneven airflow at the outlet, resulting in noise; On the other hand, due to the uneven distribution of the pressure on the blade itself and the blade, the disturbance to the surrounding gas and parts during rotation also constitutes a rotating noise; In addition, the turbulent boundary layer, vortex and vortex separation are generated when the gas flows through the blade, which cause the fluctuation of pressure distribution on the blade and generate vortex noise. The noise caused by these three reasons can be comprehensively called "shearing noise". Generally, the shearing noise of large industrial fans with large air volume and pressure is also large.

2. Vibration

If the physical center of mass of the rotor and the center of inertia of the shaft are not on the same axis when the large industrial fan rotor rotates, it will cause the imbalance of the rotor. The closest distance between the physical center of mass of the rotor and the inertial center of the shaft is called eccentricity. The eccentricity is caused by the imbalance of the rotor. When the rotor rotates, a force is generated on the shaft support due to the centrifugal force, which forms vibration, and the vibration is transmitted to all parts of the machine through the basic path.

3. Abnormal sound

The wind noise only sounds like pure wind noise, but the abnormal sound is different. When the large industrial fan is running, if there are other sounds besides wind noise, it can be judged that the large industrial fan has abnormal sound. Abnormal sound may be caused by collision due to foreign matters or deformation in the bearing, improper assembly, or looseness caused by uneven winding of the motor winding.

The first two are normal "noises". If it is the third, it should be noted. Although there is no major problem, it is better to take precautions. After all, safety comes first!