The heat dissipation capacity of the cooling system mainly depends on the heat dissipation performance of the radiator. The wind speed distribution and air volume of the radiator determine its heat dissipation performance. In order to accurately predict the surface wind speed distribution and air volume of a radiator, based on computational fluid dynamic (CFD), STAR-CCM + software is used to analyze its wind speed and flow field, and the results are compared with the test results of impeller anemometer and wind tunnel. The results show that the error between the air quantity measured by the impeller anemometer and the CFD prediction result is about 16%, and the error between the air quantity measured by the radiator wind tunnel and the CFD prediction result is about 7%. Through experimental verification and error analysis, the CFD prediction model can truly reflect the air quantity of the radiator. The reason for the large air quantity measured by the impeller anemometer is the high wind speed and statistical error. The best method for measuring the air quantity of the radiator is the radiator wind tunnel experiment. The research results can provide simulation data support and theoretical guidance for the evaluation of radiator air quantity.