Experimental study on a hybrid loop heat pipe

A conventional loop heat pipe two-phase heat transfer device of passive system often can no longer meet the challenging cooling needs due to the inherent limitations of the capillary pumping which can lead to dry out. This study aims to create a loop heat pipe uses capillary wick copper sintered with centrifugal casting method. The stressing effort to overcome the dry-out by adding a diaphragm pump to accelerate the fluid transportation from the condenser to the evaporator (hybrid loop heat pipe, HLHP), where the pump is equipped with a reservoir and both installed on the liquid line. In testing the performance of HLHP also varying the filling ratio, FR: 50%, 60%, and 80%. The pump will be activated when the dry-out took place, by the piezo electric diaphragm pump with temperature controller installed in the evaporator that was set to activate the pump to work. From the results of the experimental, the pump successfully prevented the occurrence of dry out, and reduced the temperature of the evaporator from 130°C to 80°C, owing the pump distributed the working fluid from the condenser to the evaporator efficiently. The result indicated the best performance of HLHP was filling ratio, FR of 60%.