Performance characterization of a novel flat plate micro heat pipe spreader

A combined numerical and experimental investigation was conducted on a novel flat plate micro heat pipe spreader, to better understand the effect of primary operating parameters governing the performance of such devices. A numerical thermal model was developed to predict the temperature response with variation in the leading geometrical, material and boundary parameters of the spreader, viz. wall thickness, thermal conductivity, power input and heat source size. The results showed that, unlike conventional heat pipes, wall thermal conductivity is a major factor in such thin, flat spreaders. The spreader performance also degrades with decrease in heat source size. Visualization experiments have been conducted to qualitatively understand the heat transfer phenomena taking place on these devices. These confirmed that the primary limitation to heat transfer from these devices was due to the capillary limitation of the wick structures.