Comparative Performance Analysis of an Electric Motor Cooling Fan with Various Inlet Vent and Blade Shapes

Abstract

Electric motors are used as the main power sources in many industrial equipments and household appliances. The miniaturization and weight reduction of electric motors generally increase the internal heat generation. Therefore, it is important to understand the flow characteristics of motor cooling fans and to improve their performance. The present study aimed at systematically investigating the effects of the inlet vent and blade shapes on the aerodynamic performance of a low-voltage electric motor cooling fan. The flow characteristics of the low-voltage electric motor cooling fan was numerically analyzed using three-dimensional Reynolds-averaged Navier-Stokes equations. The k-ε turbulence model was selected for the analysis of turbulence using a turbulence model test. An optimal grid system in the computational domain was selected through a grid dependency test. The mass flow coefficient and torque coefficient were considered as the performance parameters of the cooling fan. Eleven inlet vent shapes and eleven blade shapes of the cooling fan were tested by evaluating the aerodynamic performance of the cooling fan. The mass flow coefficient and torque coefficient were considered as the performance parameters of the motor cooling fan. Eleven inlet vent shapes on the fan cover and eleven blade shapes were tested to evaluate their effects on the mass flow coefficient and torque coefficient. The maximum mass flow coefficient of 0.0908 and the minimum torque coefficient of 0.0089, were achieved using different combinations of vent and blade shapes.