Heat Transfer Performance of an Ultra-Thin Loop Heat Pipe for Thin Electronics Cooling

Abstract

In this study, we newly developed an ultra-thin loop heat pipe (UTLHP) with a thickness of 0.3 mm as a useful heat diffusion device. Two types of UTLHPs with different wick shapes were fabricated and their performance was compared (UTLHP-a, UTLHP-b). A step-up heat load test was conducted to evaluate the UTLHPs performance. Tests were conducted in five different orientations to verify the effect of operating orientation on performance. In the case of UTLHP-b, the UTLHP performed heat transport of more than 9.5 W (9.5 W/cm²) and the thermal resistance was less than 1 °C/W in all orientations. The minimum thermal resistance was approximately 0.02 °C/W.