Finite Element Analysis And Experimental Study On The Thermal Resistance Characteristics Of Motor Coolers

Motor coolers are operated with the coupling of temperature and pressure fields, in which the change rule is affected by multiple factors. In this study, the thermal resistance of the motor cooler was examined using the velocity coefficient method to reveal the influence of heat transfer and wind resistance. The temperature and pressure fields were analyzed using the finite element method based on the hydrodynamics and momentum theorem. By varying the heat transfer and wind resistance coefficients to reflect temperature and pressure characteristics, wind and water velocities were determined. Results demonstrate that the total convective heat transfer and wind resistance coefficients of the cooler model are sensitive to variations in face-to-face wind velocity, but not to those of the cooling water flow rate. When wind velocity increases from 0.8 to 5.19 m/s, the total convective heat transfer increases by 1.85 times and wind resistance increases by 18.74 times. Variations in cooling water velocity has little effect on the Nusselt number on the air side and the Euler number of the single row tube, which are multiplied with the increase of the Reynolds number. When the Reynolds number increases from 1020 to 6345, the Nusselt number increases by 2.05 times and the Euler number decreases by 2.29 times. The results provide references for the design and performance testing of high-power motor coolers.