Investigation of the Thermal Performance Characteristics of a Variable Conductance Arterial Heat Pipe

Abstract

A single-artery variable conductance arterial heat pipe was experimentally and numerically studied. To investigate the growth of the noncondensible gas supported bubbles, one-dimensional time-dependent conservation equations were solved by using the finite element method. It was shown that the time of collapse for the diffusion-controlled bubbles was relatively short in the condenser. However, the bubbles grew very rapidly in the evaporator even at moderate superheat levels, which demonstrated that the heat pipe would experience arterial blockage and subsequent dryout without vapor venting pores. An optimum diameter and spacing for the venting pores were calculated to maximize the heat transfer limit and minimize the pressure drop. Test results demonstrated heat load limits up to 120 W and a narrow temperature control range.