Numerical Study of Flow and Heat Transfer of Water in a Motor Cooling System of Electric Vehicle

Abstract

This research focuses on a numerical study of water flow and heat transfer in a motor’s cooling system using the commercial computational fluid dynamics package, ANSYS-Fluent. A three-dimensional model of water in rectangular was created to have a width of 25 mm, a height of 5.45 mm, and a gap between the channels of 10 mm. The Realizable k-e turbulence model and Standard wall function were used for the computational analysis. The boundary condition of heating walls was defined to be the constant heat flux of 56,523.15 W/m². The water temperature at the entrance of the cooling motor jacket was set to 50 °C and the velocity of 2.4, 4.8, 7.2, 9.6, and 12 liters per minute. The numerical results of flow and heat transfer of water in 3 types of flow channels showed that flow patterns in a cooling system affected the outlet temperature and pressure loss. The change in flow pattern caused the increase in the Nusselt number and the thermal performance factor up to 45.39 % and 31.25%, respectively. Therefore, this research will be important information, leading to the design and development of motor cooling systems to be more efficient in the future.