Abstract
This paper describes experiments and the analysis of the heat transport capability of axial grooved heat pipes. The heat pipes were made of copper tubes with axial grooves and working fluid was H_2O. Outer diameter and length of the heat pipe were 8mm and 300mm. The width and height of the grooves were 0.19mm and 0.2mm and the number of grooves was 75. The effects of the fluid inventory, inclination angle and working temperature on the capillary limit were investigated. The following conclusions were obtained from the experiment and theoretical analysis. (1) The heat pipe showed maximum heat transfer rate of 100 W at 200℃ working temperature under horizontal setting condition and can operate under inclination of 70mm height difference at 50℃ working temperature. (2) The maximum heat transfer rate was increased in proportion to fluid inventory due to the increasing length of the liquid slug generated at condenser end. Evaporative and condensing heat transfer coefficients were also investigated experimentally.
