First of all, many people find that the structure of the cooling axial fan blades is composed of odd numbers such as 3, 5, 7, 9 and 11. However, many consumers are not very familiar with it, and are curious, whether this is just a design coincidence or another mystery Where?

As we all know, the actual heat dissipation effect of a cooling fan largely depends on the design of the blade pitch and the number of blades. Among them, the number of leaves plays an important role. Generally, in the design of the fan, the manufacturers of cooling fans all adopt the method of increasing the number of blades to ensure a certain air volume and pressure.

This is because odd-numbered blade combinations can bring more performance advantages than even-numbered blade combinations. Because the even-numbered axial fan blades are symmetrical, this not only makes it difficult to adjust the balance of the fan itself, but also makes the high rpm cooling fan generate more resonance when running at high speed, which makes the blades unable to withstand the fatigue caused by resonance for a long time. There is a blade break, etc. Therefore, most axial fans are designed with asymmetrical odd-numbered blades.

Generally speaking, narrow blades have a larger blade pitch, which will cause airflow to be dispersed and weaken the cooling performance of the fan. If the axial fan blades are added, the spacing will be reduced and the air flow will be more concentrated, thereby improving the cooling performance of the fan.

Large air volume axial fan, When other parameters remain unchanged, the more axial fan blades, the greater the air volume. The main reason is that the blade divides the airflow into several parts, so the pressure of the airflow on the fan blades will be correspondingly reduced, and the friction between the airflow and the blades will also be reduced accordingly.

With the increase of the axial fan blades, the friction between the airflow and the blades is reduced, and the corresponding noise is also reduced, but the wind shear noise is not considered, and its increase will cause the wind pressure to drop.