Effect of Fan Hub Configuration on the Cooling Airflow through Electric Motors in Engine Cooling Fan Systems

Typical automotive engine-cooling fan assemblies include an electric motor having a driveshaft coupled to a fan. The typical fan includes a hub, which extends from the driveshaft to the root of the fan blades. Radial ribs are incorporated within the hub to stiffen the fan structure. The fan hub including the ribs pulls cooling air through the motor, thus preventing it from overheating.

Experimental tests and computational fluid dynamics (CFD) simulations have been carried out to investigate the effects of fan hub configurations on cooling airflow through the electric motor in automotive cooling fan systems. It has been found that radial ribs on the fan hub have significant effects on drawing cooling air through the motor. The comparison of the simulation results with the pressures measured in laboratory experiments show good agreement.