A DC blower is a type of fan used in network servers and telecommunications systems with high impedance from back pressure. These types of fans contain a circular impeller within an enclosed cage, which is often referred to as a "squirrel cage". This design allows DC Blowers to create directed airflow under high pressure conditions. A DC Blower has a more concentrated airflow in which the equipment pulls air in from the sides and forces it out at a concentrated 90º angle.
There is a distinct difference between fans and blowers. Axial fans create an air flow that is parallel to the axis of the fan blade. DC blowers, on the other hand, send air on a perpendicular direction in relation to its axis. The fan design allows blowers to provide air flow at a high flow rate. It works against low pressure. The design of DC Blowers allows them to use low rate air flow against high pressure.
There is a difference in the compression ratios that fans and blowers offer. Fans have compression ratios close to 1.1. Blower fans, on the other hand, have compression ratios between 1.1 and 1.4. They can, therefore create moderate increases in pressure when pushing air (or other gases) through the machine.
You will find that there are two basic types of DC blowers: tube axial and vane axial. Tube axial models are fabricated with the fan element inside a duct station. In general, tube axial blower fans are easier to install because they are the standard in many industries.
Vane axial blower fans have the propeller element installed inside a cylinder. One end of the vane axial blower fan’s cylinder is open to allow air to flow into the tube easily. The other end, however, has slanted walls that concentrate and straighten air as it exits the blower. The vane axial blower fans correct any problems caused by air exiting the blower in erratic directions.
DC Blowers are used in various industries and devices. From office automation equipment and projectors to portable consumer products, axial blowers serve a very specific function and are designed to provide the most efficient air flow necessary to get the job done.