Abstract
In the recent years, complying with increase of the transistor density, heat generated from these electronic devices was usually grown doubly. Due to the reason of the tiny heat source area, the heat flux turn out to be very large and result in the difficulty of the heat dissipation. The purpose of this study was trying to develop a micro-capillary-pumped-loop (μ-CPL) that could carry away 3W of the heat by means of the natural convection. From the observation of the transparent loop, one may found the vapor generated from evaporator was pushing out to the evaporator line and condensed to the liquid form at condenser section then back to the evaporator periodically. The experimental result was shown the contact resistant between evaporator and copper rod was related to the fixed pressure. For a typical case, at 3W heat input with surrounding temperature 30℃, the CPU temperature was 79℃ and the thermal resistant was 16.3(℃/W) as fixed pressure in 3kg. The micro CPL was cooed by a water jacket, therefore the cooling water temperature affected the thermal resistance of the CPL as well. When the cooling water temperature was above 25℃, the thermal resistant was 17.5(℃/W) and the fluid flow in the loop was not apparent. When the cooling water temperature was down to 10℃, the thermal resistant was 15.9(℃/W). There were two different evaporator structures, parallel and nozzle. Test results showed the performance of these two structures weren’t different too much in this study.