Cooling fans , English name: Cooling fans. The technology and performance of cooling fans have fully reached a mature stage, and new technologies are constantly emerging. Fan specifications range from 8mm to 280mm, voltages include 5V, 12V, 24V, 48V, 110V, 220V, 380V, and shapes include square, round, olive, etc.

The working principle of the cooling fan is based on energy conversion, that is, electrical energy → electromagnetic energy → mechanical energy → kinetic energy. Its circuit principle is generally divided into many forms, and the performance of the fan will be different depending on the circuit used.

1. Axial flow fan

The blades of an axial fan push the air in the same direction as the axis. The impeller of an axial fan is somewhat similar to a propeller. When it is working, most of the airflow flows parallel to the axis, in other words, along the axis. The power consumption of an axial fan is the lowest when the inlet airflow is free air with zero static pressure. When it is running, the power consumption will increase as the back pressure of the airflow increases. Axial fans are usually installed on the cabinets of electrical equipment, and sometimes integrated into the motor. Due to their compact structure, axial fans can save a lot of space and are easy to install, so they are widely used. 

Its characteristics: higher flow rate, medium wind pressure

2. Centrifugal fan

When a centrifugal fan is working, the blades push the air to flow in a direction perpendicular to the axis (i.e. radial direction). The air intake is along the axis direction, while the air outlet is perpendicular to the axis direction. In most cases, an axial flow fan can achieve the cooling effect. However, sometimes if the airflow needs to be rotated 90 degrees or a higher wind pressure is required, a centrifugal fan must be used. Strictly speaking, a blower is also a centrifugal fan. 

Its characteristics: limited flow rate, high wind pressure

3. Mixed flow fan

Mixed flow fans are also called diagonal flow fans. At first glance, mixed flow fans are no different from axial flow fans. In fact, the air intake of mixed flow fans is along the axis, but the air outlet is along the diagonal direction of the axis and the vertical axis. This type of fan has a higher wind pressure because the blades and the outer cover are conical. Compared with axial flow fans, centrifugal fans have lower noise at the same size and other comparable performance. 

Its characteristics: high flow rate and relatively high wind pressure

4. Crossflow fan

Crossflow airflow can generate large-area airflow and is usually used to cool large surfaces of equipment. The air inlet and outlet of this fan are perpendicular to the axis (as shown in the right figure). The crossflow fan uses a relatively long cylindrical impeller to work. The diameter of the cylindrical impeller is relatively large. Because of the large diameter, a relatively low speed can be used on the basis of ensuring the overall air circulation volume, thereby reducing the noise caused by high-speed operation. 

Its characteristics: low flow rate, low wind pressure