The performance of the novel vapor chamber based on the leaf vein system

With the upgrade of the miniaturization of the electronic equipment, heat in per area increases dramatically, which leads to the strong need for a high efficient device of heat dissipation. As the result of the nature evolution, leaf vein system is an excellent structure for heat and mass transfer but has not been widely studied. Based on the leaf vein system, a conceptual structure is designed to form the wick of a vapor chamber, in which the leaf-vein-like fractal network and the micro fin-pins are used to simulate the leaf vein network and mesophyll tissue respectively. In the experiment, the leaf-vein-like structure is manufactured by chemical etching, and two different vapor chambers (diameter is 90 mm, the evaporator and condenser have the same wick structures) with and without strength boiling are compared concerning their cooling performances. The experiment result shows that when the diameter of the heating rod is 35 mm, the vapor chamber can perform good temperature uniformity and small thermal resistance with the input power Q ⩽ 90 W. When the deionized water is used as the working fluid, the thermal resistance of the vapor chamber is smaller than 0.3 °C/W.