Abstract
Abstract The capillary pumped loop (CPL) was first invented by F. J. Stenger in the mid-1960’s at NASA/Lewis. CPL is a high efficiency two-phase heat transfer device using the phase change of working fluid to transport heat from evaporator to condenser; it’s a cyclic circulation pumped by capillary force. Since CPL doesn’t need any other mechanical force such as pump, it might be used to do the thermal management of high power electronic component on spacecraft. This study presents the application of CPL to electronic cooling system on the ground with a horizontal position (0-g environment) and scale down the whole device to the miniature size (range from mm to cm). This miniature-CPL is made of aluminum with the shape of evaporator be 10x30x40 mm cubic; the vapor/liquid lines are smooth round tubes of 360/80 mm in length and 3.5mm in both inner diameter. The cooling of condenser is achieved by forced convection because that’s the most common way of current electronic cooling system. Testing results show that the miniature-CPL could remove heat 25W in steady state and keep the heat source temperature under 100oC. The thermal resistance of this CPL is about 2.6K/W. Operating characteristics under various conditions including start-up time, steady state performance, transient phenomena in different heat loads, step-up heat loads and low power heat load operating are presented. Peculiar behaviors such as the hysteresis and overshoot of the temperature are also observed in this study.