Many customers who purchase a cooling fan and use it for a period of time may find that there is a certain amount of noise generated. They may wonder if it is broken and where the noise actually comes from. Today, Emory Electronics will popularize that the main sources of noise from the cooling fan are as follows:
1. Fan vibration. If the physical center of mass of the fan rotor is not on the same axis as the center of inertia of the shaft when the fan rotor rotates, it will cause imbalance of the rotor. The closest distance between the physical center of mass of the rotor and the center of inertia of the shaft is called eccentricity. Unbalance of the rotor causes eccentricity. When the rotor rotates, a force is generated by the centrifugal force on the shaft support, forming vibration, and the vibration is transmitted to various parts of the machinery through the basic path. 2. When the fan is working, noise is generated due to the periodic pulsation force of the uneven airflow at the outlet borne by the blades; On the other hand, due to the uneven distribution of pressure on the blades themselves and on them, the disturbance of surrounding gases and parts during rotation also constitutes rotational noise; In addition, due to the turbulent boundary layer, vortex, and vortex detachment generated when gas flows through the blades, the pressure distribution on the blades is pulsating, resulting in vortex noise. The noise caused by these three reasons can be comprehensively referred to as "wind cutting noise". Generally, fans with high air volume and pressure also have higher wind cutting noise. 3. Fan abnormal sound: Wind noise only sounds like pure wind sound, while abnormal sound is different. When the fan is running, if there are other sounds besides wind sound, it can be determined that the fan has abnormal sound. Abnormal noise may occur due to foreign objects or deformation inside the bearings, as well as collisions caused by improper assembly, or uneven winding of the motor, resulting in looseness and detachment. The noise of the fan is mainly generated by the above points, so it is normal for the fan to have noise during use. Each fan has a noise value, and as long as it is within this range, it will not affect the normal use of the fan, so you can use it with confidence.
