Optimization of the airside thermal performance of mini-channel-flat-tube radiators by using composite straight-and-louvered fins

Abstract

In this study, to optimize the thermal performance on the airside of a flat-tube radiator, four parameters, including fin types, fin pitch, fin thickness, and louver angle, are numerically examined in detail. Existed experimental results are employed to verify the present numerical method with maximum deviations to be less than 1.65%, and 0.27% for heat transfer rate and outlet temperature, respectively. The frontal velocity ranges from 1 m/s to 6 m/s. Copper and aluminum are employed as the tube and fin materials, respectively. For all cases in this study, it is found that the thermal performance is significantly affected by the fin thickness, fin pitch, and fin types. The thermal performance significantly increases with the increase of the louver angle from 0° to 27°; however, it is only slightly increased with a further rise of the louver angle from 27° to 40.5°. A novel composite straight-and-louvered fin structure is proposed, and an optimal fin structure is found. The optimal fin structure could improve the thermal performance up to 17.52%, 18.31%, and 19.54% or 55.76%, 59.27%, and 60.22% compared to that of the SD louvered fin or the baseline at pumping powers of 2 W, 10 W, and 20 W, respectively.