Development of lotus-type porous material for heat pipe application using centrifugal slip casting process

Abstract

Heat pipe is a heat conductor which has a large conduction capacity using a special fluid-filled pipe as a conductor of heat from the hot end (evaporator) to the cold end (condenser) used for thermal management. In the heat pipe, there is a sintered wick which transfers refrigerant fluid from condenser to evaporator. The objective of this research is to improve capillary performance by making a straight pore called as lotus-type porous material (LTP) using centrifugal slip casting technique. Copper powder is used as wick materials due to its high thermal conductivity. A starch solution is used as binder material to make the copper slurry. Nylon wire is applied as straight pore mold. Freeze drying is applied to curing and demolding. Vacuum sintering is conducted to increase metallurgical bonding between the particle. The results show that centrifugal casting machine is capable to make a wick with LTP structure. On the performance department, capillary pumping is affected by rotation speed, powder size, and powder loading. The optimum parameters were copper powder with 260.54 μm powder size, 50% Powder Loading with 688 rpm rotation speed. The LTP wick is proved to have a higher capillary pumping capacity compared to the conventional wick. Further work is necessary to verify the performance of LTP wick in the heat pipe.