Effect of Inclination Angle on the Heat Transfer Performance of a Closed Loop Oscillating Heat Pipe with Check Valve (CLOHP/CV) and Fins on Tube Wall

บทคัดย่อ

Abstract

This research aims to study the effect of inclination angle on the heat transfer performance of a Closed-Loop Oscillating Heat-Pipe with Check Valve (CLOHP/CV) with fi ns on the tube wall. The heat pipe was made from a copper pipe, and the capillary tube had a 5.0 mm inside diameter. There were 24 meandering turns with two check valves.The lengths of the evaporator section and condenser section were 200 mm and the adiabatic section was 100 mm.The working fluid used was water with a filling ratio of 50% of the total volume of the tube. The temperatures for the evaporator section were 60, 70 and 80oC. Inclination angles were 0, 20, 40, 45, 60, 80 and 90 degrees from the horizontal axis were established. It was found that when the variable temperature increased from 60, 70 to 80 oC heat flux and thermal efficiency increased. In addition, when the inclination angle increased from 0, 20, 40, 45, 60, 80 and90 degrees heat flux and thermal efficiency increased. Therefore, this research concluded, from the experiment that the heat pipe was a CLOHP/CV. The maximum specific heat flux equaled 1,926.97 W/m2 and the maximum thermal effectiveness equaled 0.44, the operating temperature was 80 °C and an angle of inclination to the horizontal axis was 90o

Keywords: Oscillating heat pipe, Check valve, Inclination angles, Heat transfer, Fin