Power-saving exploration for high-end ultra-slim laptop computers with miniature loop heat pipe cooling module

Abstract

In this paper, an active air-cooling module based on a 1-mm-thick ultrathin miniature loop heat pipe with a flat evaporator for high-end ultra-slim laptop computers is presented and studied. Systematic experimental investigations were conducted under natural air convection and forced air cooling conditions with different fan voltages. The results indicated that the miniature loop heat pipe module could effectively dissipate a heat load of 12 W at all test orientations under natural convection with zero power consumption when the chip-junction temperatures were below 85 °C. Under forced air cooling, the proposed miniature loop heat pipe module had almost identical cooling performance at all test orientations when the fan input voltages were changed from 5 V to 2 V. Aided by infrared photography and theoretical analysis, the unique operation mechanism for the module was revealed. Finally, in a 35 °C temperature humidity chamber, the module could dissipate 25 W at a fan voltage of 5 V (22 W at 2 V) with the chip-junction temperature below 85 °C, showing a promising and energy-saving thermal management solution for high-end ultra-slim laptop computers. The results indicate that by using the proposed module, cooling energy savings of up to 80% could be realized compared to the current applied miniature heat pipe module in a laptop computer.