Experimental Investigation of the Effect of Condenser Configuration on a Horizontally Rotating Wickless Heat Pipe Performance

This experimental study investigates the effect of condenser configurations on the thermal performance and operational characteristics of a horizontally rotating heat pipe. The investigated parameters include three condenser lengths (112.5, 150, and 187.5mm), outer condenser conical ends (60, 80, and 100), and inside condenser tapered angles (1, 2, and 3). An experimental apparatus was designed, constructed, and commissioned with nine condenser sections to explore the effect of condenser configuration on the steady-state thermal performance of heat pipes. The heat pipe is tested at a constant speed of 1500 rpm and various heat loads ranging from 25-200 W, using water as the working fluid. Results indicated that under a constant filling charge equals the inside evaporator volume, the best condenser length of the heat pipe equals the evaporator length. On the other hand, under a variable filling charge equals 0.25 the inside pipe volume, the best condenser length equals 1.25 the evaporator length. The condenser with a conical end of 60 enhances the heat pipe performance by about 37.5-60% over the plain condenser. However, the condenser with a tapered angle of 3 produces the best heat pipe thermal performance compared to the conical end or the different-length condensers. The tapered condenser with an angle of 3 enhances the heat pipe thermal conductivity over the plain condenser by 33.3-257.8%. Also, it achieved higher thermal conductivity than the condenser with a conical end of 60 by 16.6-125.0%.