The technology and performance of the cooling fan have fully reached a mature stage, and new technologies are constantly emerging.
So, what are the basic classifications of cooling fans?
Axial flow fan
The blades of an axial fan push air to flow in the same direction as the shaft. The impeller and propeller of an axial flow fan are somewhat similar. When it works, the majority of the airflow flows parallel to the axis, in other words, along the axis direction. When the inlet airflow of an axial flow fan is free air with zero static pressure, its power consumption is the lowest. When operating, the power consumption will also increase with the increase of the airflow back pressure. Axial fans are usually installed on electrical equipment cabinets and sometimes integrated into motors. Due to their compact structure, they can save a lot of space and are easy to install, making them widely used.
Its characteristics: high flow rate, moderate wind pressure
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). The intake is along the axis, while the outlet is perpendicular to the axis. In most cases, using an axial fan can achieve cooling effect. However, sometimes if the airflow needs to rotate 90 degrees to exhaust or when a large air pressure is required, a centrifugal fan must be selected. Strictly speaking, fans also belong to the category of centrifugal fans.
Its characteristics: limited flow rate, high wind pressure
Mixed flow fan
A mixed flow fan, also known as a diagonal flow fan, is no different from an axial flow fan at first glance. In fact, the inlet of a mixed flow fan is along the axis, while the outlet is along the diagonal direction of the axis and vertical axis. This type of fan has a higher wind pressure due to the conical shape of its blades and casing. Compared to axial flow fans, centrifugal fans have lower noise under the same size and other comparable performance.
Its characteristics include high flow rate and relatively high wind pressure
Cross flow fan
Cross flow air flow can generate a large area of air flow, usually used for cooling large surfaces of equipment. The inlet and outlet of this fan are both perpendicular to the axis (as shown in Figure 1). The cross flow fan uses a relatively long cylindrical fan impeller for operation, and the diameter of the cylindrical fan blades is relatively large. Because of the large diameter, it is possible to use a relatively low speed while ensuring the overall air circulation, thereby reducing the noise caused by high-speed operation.
Its characteristics: low flow rate and low wind pressure