Axial fans are a type of compressor that increases airflow pressure as it passes through. The fan blades work by forcing air to move parallel to the shaft, which the blades rotate around. Ultimately, the axial flow fan characteristics cause air to flow axially. DC fans are fans that are powered by the direct current. Like AC Axial fans, there are DC axial fans and DC cross flow fans too. DC axial fans are widely used in the air-vent exhaust, electronic device cooling, computer ventilation, etc.
Generally, DC fans are used as chassis fans with low power consumption. They are supplied with DC power. These fans are also called 3-pin fans, as they come with 3 pins. The 3 pins are the supply pin (usually 12 V DC), ground pin, and a signal pin. Direct current is used in any electronic device with a battery for a power source. It is also used to charge batteries, so rechargeable devices like laptops and cell phones come with an AC adapter that converts alternating current to direct current.
In general, an axial-flow fan is suitable for a larger flow rate with a relatively small pressure gain and a centrifugal fan for comparatively smaller flow rate and a large pressure rise. They are used to supply fresh air, to suck air from return air trenches, to suck air from rotary filters, to exhaust air out etc.