The fans look the same, but the size is different, but why some fans can be used for a long time, and some will be broken within two days? This is caused by the structural difference of the fan itself.

Oil bearing fan

Oilimpregnated bearings are sleeve bearings that use sliding friction and use lubricating oil as a lubricant and drag reducer.

Magnetic levitation fan

The magnetic bearing fan is actually an improved self-oil bearing fan. It uses the principle of magnetism. The magnetic induction line is perpendicular to the maglev line, and the shaft core is parallel to the maglev line. The weight of the rotor is fixed on the running track, almost without load. The shaft core is propped up in the direction of the anti-magnetic levitation line to form the entire rotor suspended running track. The advantage is that it is quiet and has a relatively long life.

Single ball fanThe singleball fan adopts a mixed form of sliding friction and rolling friction. In fact, it is a combination of a ball bearing and an oil bearing. This kind of fan is not expensive, and overcomes the shortcomings of short life of oil-impregnated bearings, and has a relatively long life. But the disadvantage of the single ball fan is that the noise is increased.

Double ball fan The price of the double ball fan is second only to the magnetic levitation fan. Due to the double-layer ball structure, there is no oil leakage problem, and the airtightness of the bearing is best not easy to wear out, so its life is the longest. Many violent fans use double balls, and the disadvantage is also quite fatal: the noise is huge.

Air volume, wind pressure, a CP combination that loves and kills each other

Regardless of the fan technology, the current passes through the control circuit to generate a rotating magnetic field at the stator coil and the electromagnet, which pushes the magnet on the rotor to rotate in a specific direction, thereby driving the entire fan blade to rotate at a high speed, and pushing the air quickly from Passing through the fan blades, it has reached a specific air volume and pressure. What are these two?

The wind pressure is the pressure of the wind. The greater the wind pressure, the greater the force of the wind, which makes it easier to blow through the chassis punching, dustproof net and other components. The air volume can be understood as the amount of air flow through the fan at the same time. At the same time, more air flow can be exchanged to improve the heat dissipation effect. However, the relationship between air pressure and air volume is relative. At the same speed, the greater the fan's air pressure, the smaller its air volume, and vice versa.

In addition, two factors, the angle of inclination of the blades of the fan and the curvature of the blades, will affect the wind pressure value of a fan to a large extent. The larger the blade inclination angle and curvature value, the greater the wind pressure at the same speed. As long as the speed is controlled, this fan is very suitable for use on the front panel of the chassis (generally, a silent fan with 800 rpm is recommended for chassis fans) .

A fan with a large air volume is more suitable for use as a fan at the rear of the chassis. So if it is a desktop computer with a cooling fan, don't think that it is enough to buy one-to-one exactly the same, it is best to distinguish.

The voltage is different, the fan is different

Fans are not only different in appearance and size, such as 80mm, 92mm, 120mm, 140mm or even 200mm, but also in terms of voltage. At present, cooling fans are mainly divided into two voltage specifications, 5V and 12V. The common CPU and graphics fans are all 12V, and the same is true for chassis fans. The notebook radiator needs to be powered by the USB interface, so basically 5V fans are used. Therefore, when buying a fan for your computer, you must figure out where you will use it.

Last but not least, when configuring a cooling fan for the computer, I recommend buying a silent fan, usually an oil-bearing fan below 1200 rpm. Pay attention to the blades, the smaller the tilt angle, the lower the noise.