Numerical Investigation on Heat Dissipation Performance of Multi-Fan Cooling Module

To study the heat dissipation performance of the multi-fan cooling module composed of multiple fans and a radiator, numerical models of the radiator and the multi-fan cooling module were established, and heat dissipation performance prediction analysis and application analysis were conducted. In modeling, the Effectiveness-Number of Transfer Units (ε − NTU) method is used to predict the heat dissipation performance of the radiator. The aerodynamic performance of the fan at any speed is obtained by the similarity theorem using the data obtained from the tests at a certain speed. The influence between the fan and the radiator was established by using the flow addition scheme. To validate the established model, heat dissipation performance using 36 radiators and 11 multi-fan cooling modules is measured, and the measured data are compared with the calculations. The results show that: (1) For the radiator model, relative errors of heat dissipation are below 15.03%, and the absolute error of the outlet temperature is less than 1.6 °C. (2) For the multi-fan cooling module Relative errors of heat dissipation are within 13.34%-18.35%, and the absolute error of the outlet temperature is less than 4.3 °C. Considering the difficulty of obtaining the radiator structural parameters, the ε − NTU model with a semi-empirical formula with multiple sets of operation points as input is proposed, and the model verification error is below 6.86%. This method can predict the heat dissipation of different core sizes, and the calculation error is within 20%. For fan control, this article demonstrates that partial activation of the fan is beneficial to reducing fan energy consumption under low heat source conditions.