Numerical and experimental investigation of the operating characteristics of a “wickless” heat pipe

SYNOPSIS

This paper describes existing numerical techniques used for simulating heat pipes, and the development of a simplified numerical model for normal wicked/wickless heat pipes based on the analysis of the current modelling methods. The model was used to investigate the operating characteristics of a “wickless” gravitational heat pipe, including variation of cross-sectional area, axial/radial velocity, pressure and temperature of liquid/vapour flows with height position above the liquid level. To validate the modelling predictions, a test rig was constructed to carry out laboratory testing, including measurement of surface temperatures and heat flow associated with the heat pipe heat transfer. Experimental results were found to be in general agreement with the numerical predictions when the test conditions were close to the simulation assumptions.