Study Of A Novel Skew-grooved Wick Structure For Micro Heat Pipes

With the rapid development of Microelectronic Technology, micro heat pipe with highthermal conductivity, high reliability and fast thermal response has become ideal conductingelement for most electronic products. The heat transfer performance of micro heat pipe isobviously dependent on the wick structure inside the heat pipe. As a result, the wick structurehas long been a hot topic of foreign and domestic research.The micro-grooved wick meets to the trend of small and lightweight for the electronicelements. Aiming at the problem of the lack of capillary force, a novel skew-grooved wickwas proposed for micro heat pipes. Through a theoretical analysis of the wick structure, theadvantages of skew-grooved wick with regard to the capillary force have been verified. Inadditional, the skewed angle and other structure parameters are designed to process thefinished skew-grooved wick by high-speed oil-filled spinning.Risen meniscus experiments were carried out to research the capillary force by IR thermalimaging camera. The results indicate: the maximum capillary force of the skewed-groovedwick is8.62%larger than that of the rectangle-grooved wick. The results also show that thelarger the degree of skewed angle, the larger the capillary force, but the larger the groovewidth, the smaller the capillary force.The feasibility of skew-grooved wick applied to micro heat pipe is analyzed, and theexperimental investigation on start-up performance and isothermal characteristics of micro skewed-grooved heat pipes are presented. The results show that the micro skewed-grooved heat pipehas a good start-up performance and isothermal characteristics between40℃and80℃heatingconditions. Through comparison analysis of the micro rectangle-grooved heat pipe and microskewed-grooved heat pipe, it shows that the skewed-grooved heat pipe has the better start-upperformance for the larger capillary force and it not only has the equally good isothermalcharacteristics but also a lower wall temperature of the lower side of condensation section.