Pages: 1-12

Abstract

In recent years, there has been increased tendency toward using heat pipe technology in order to recover heat, save energy and prevent loss in various engineering applications. Heat pipes have important role in many industrial applications, especially in heat exchangers' function improvement and energy saving. In this study, a comprehensive modelling has been conducted for the numerical simulation of the details of two-phase flow and heat transfer phenomenon in wickless heat pipe (Thermosiphon) so that these details cannot be observed in laboratory experiments. Water has been chosen as the fluid and the Volume of Fluid (VOF) of ANSYS FLUENT software is used to model the two phase of water and vapor in thermosiphon. Boiling and condensation (phase transformation) processes in thermosiphon are modelled by coding and adding an UFD code to the FLUENT software. Then, the simulation results are compared to the experimental measurements with the same parameters. Comparison of the results showed that the current modelling in simulation of the heat and mass transfer phenomenon in thermosiphon was successful, and there is good consistency between the temperature profile prediction results by using simulation process and laboratory results. Also, the effect of temperature change and heat input in different times on the thermosiphon operation is studied and the changes of condensed liquid layer on the thermosiphon wall were considered.