Performance of a flat grooved heat pipe with a localized heat load

Abstract

Heat pipes are phase change heat transfer devices used in wide range of heat transport applications due to their high thermal transport capacities with low temperature differences. Heat pipes are especially preferred for electronic cooling applications and aerospace avionics to satisfy high heat transfer rate requirements. In this study, heat transfer and phase change mechanisms of working fluid are investigated and modeled using a 3-D thermal resistance network for multichannel flat grooved heat pipes. First, heat transfer and fluid flow are modeled in half of a single grooved structure due to symmetry, and is subjected to uniform heat flux. Radius of meniscus curvature and temperature distribution along the groove are calculated. Results are compared with experiments in the literature and show good agreement. The validated heat transfer and fluid flow models are extended to a multichannel model to observe performance of grooved heat pipes with localized heat sources, not covering the entire width, a vital feature for realistic simulation of operational devices. Predictions of the temperature distribution along the multichannel of the heat pipe are provided and the effect of the distribution of heat sources on the heat pipe is discussed.