Thermal management of liquid-cooled cold plates for multiple heat sources in a humanoid robot

Thermal management for two array types of a serial circulation and a two-way parallel circulation using six mini liquid-cooled cold plates were experimentally measured in this study. In order to reduce weight of the cooling devices for humanoid robot cooling, the cold plates were covered with non-metallic material (polycarbonate, PC). Six cold plates attached on 10 x 10 mm2 copper base: 0.5 x 0.5 mm2 pin-finned surfaces of 1.5 mm high with 0.5 mm array spacing, was mounted on six copper heating blocks with isothermal conditions of 50~90°C, respectively. In order to compare thermal characteristics according to two circulation types, the surface temperatures of heating blocks and the cooling water temperatures at inlets and outlets of cold plates were measured. From the results, it was found that a two-way parallel circulation was better performance than a serial circulation in terms of total thermal resistance, total heat transfer rate, and surface temperature rises from first heating block to last one for six multiple cold plates.