Experimental Research on a Honeycomb Microchannel Cooling System

A honeycomb porous microchannel cooling system for cooling electronics is proposed in this paper. The design, fabrication, and test system configuration of the microchannel heat sink are presented. Experiments were conducted to determine the heat transfer characteristics and cooling performance of this microchannel cooling system under steady single-phase flow of water. In the experiments, a brass microchannel heat sink was attached to a test heater with 8 cm² area. The heat transfer capabilities of the cooling system with different amounts of input heating power, different system designs, and various levels of pumping power were evaluated. The experimental results show that the designed cooing system performs well. For a heat sink design using double inlets and outlets, the system is able to remove a heat flux of 17.6 W/cm² under 0.72 W of pumping power, with the heater wall temperature of 61.4°C and the ambient temperature of 17.8°C. When the heat flux decreases to 9.4 W/cm² with the other conditions remaining the same, the heater substrate temperature is 42.4°C. It is also clear from the experiments that the heat source temperatures are very uniform when cooled by the present system, which is important for many applications requiring high thermal reliability. As the pumping power and system flow rate increase, the heat source temperature sharply decreases. A heat flux of 18.2 W/cm² can be removed under 2.4-W pumping power when the heat source temperature is 48.3°C and the ambient temperature is 14.9°C.