Experimental study on the thermal performance of a small-scale loop heat pipe with polypropylene wick

A small-scale loop heat pipe (LHP) with polypropylene wick was fabricated and tested for investigation of its thermal performance. The container and tubing of the system were made of stainless steel and several working fluids were tested including methanol. ethanol, and acetone, The heating area was 35 mm X 35 mm and nine axial grooves were provided in the evaporator to provide vapor passages. The pore size of the polypropylene wick inside the evaporator was varied from 0.5 μ m to 25 μ m. The inner diameter of liquid and vapor transport lines were 2.0 mm and 4.0 mm, respectively and the length of which were 0.5 in, The size of condenser was 40 mm (W) X 50 mm (L) in which ten coolant paths were provided. Start-up characteristics as well as steady-state performance was analyzed and discussed. The minimum thermal load of 10 W (0.8 W/cm(2)) and maximum thermal load of 80 W (6.5 W cm(2)) were achieved using methanol as working fluid with the condenser temperature of 20° C with horizontal position.