A capillary pumped loop (CPL) can be used as a heat transferring device for cooling electronic chips (such as CPU of a personal computer or notebook). The purpose of the paper is to investigate the parameters affecting the CPL. The thermal transport characteristics of CPL are obtained from experimental results. A 4.2×3.8×0.8 cm3 CPL was designed for the experiments. The results indicate that: (1) the device is capable of dissipating 40 W of thermal energy and keeping the chip surface temperature under 100°C; (2) the device can transfer heat from the evaporator to the condenser through natural circulation (i.e., without any external driving forces) if the relative height difference between the evaporator and condenser is greater than 1 cm. Some transport phenomena of the working fluid and the heat transfer characteristics of the loop were observed in the experiments and are discussed in detail below.
