Steady and Transient Heat Transfer Characteristics of Flat Micro Heatpipe

(PHP) and capillary pumped loop (CPL) heatpipe, and it is expected that these new heat transfer devices will possibly see practical applications. The slim-profiled flat μHP that has recently been developed is drawing attention because the heatpipe has the advantages of ease of mounting in PCs assuring a sufficient contact surface with heat-generating devices. While this flat μHP has geometrical features such that its crosssectional area of the vapor channel for the working fluid is very small in comparison with cylindrical heatpipes, the effects of this feature on the working principle and the heat transfer performance have not been clarified yet. Accordingly, this paper presents the basic data of this flat μHP together with thermal characteristics that are indispensable for optimizing its inner structure.