Patent ID: 7168918

Claim:
A cooling fan for cooling electronic components in an enclosure, the cooling fan comprising: a rotor configured to generate an airflow, the rotor comprising a number of rotor blades and a hub with a sloping configuration such that a radius of the hub increases from a leading edge of a rotor blade to a trailing edge of the same rotor blade; an outlet guide vane adapted to receive the airflow generated by the rotor and to orient the airflow in a substantially axial direction relative to the rotor, the outlet guide vane comprising a number of vanes greater than the number of rotor blades and being configured so as to cause an air static pressure rise through the outlet guide vane; and a diffuser configured to receive the airflow from the outlet guide vane and produce an airflow with higher static pressure relative to an inlet of the diffuser; wherein the rotor, outlet guide vane, and diffuser, are configured such that the cooling fan produces a work coefficient greater than 1.6 and a flow coefficient greater than or equal to 0.4.