Influence of the adiabatic section thermal break on the thermal performance of a gravity-assisted heat pipe integrating with evacuated tube solar collector Available to Purchase

This paper experimentally presents the axial conduction effects throughout the heat pipe wall on a thermosyphon effectiveness. There were two different gravity-assisted heat pipe evacuated tube solar collector (GAHP-ETSC) practically examined; both of them have the same materials, dimensions, and their heat pipes filled with approximately 70% of acetone (as a working fluid). However, the main difference is one of the gravity-assisted heat pipe has a thermal break within the adiabatic section in order to prevent the axial conduction between the condenser and evaporator parts through the heat pipe wall. Also, the two thermosyphons were exposed to various solar radiation intensities and different atmospheric temperatures. The experiments showed that the adiabatic section of the GAHP had decreased the evaporation, condensation, and overall heat transfer coefficient.