Approximate analytical and experimental analysis of thermosyphon using phase change material.

摘要

An experimental and approximate analytical study of a thermosyphon system that utilizes solid-liquid phase change material to enhance heat dissipation is presented. In this analysis, the Integral-type approximate method for solving transient conduction problems was used to predict the temperature distribution and the time-wise variation of the liquid-solid interface during the early stage of the melting process. This method decomposes the temperature distribution into two components, the quasi-steady state and the transient part.Furthermore, experimental analysis of thermosyphon phenomena during the latter stage of the phase change process are presented. Various profiles such as temperature-time, heat transfer coefficient-time, and melting front-time histories and the variation of heat transfer parameters such as Nusselt number with Rayleigh number are presented to validate the theory that thermosyphon system using solid-liquid phase change material is a good passive cooling mechanism.In the absence of the phase change process, an experimental and analytical investigation was conducted to determine the rate of heat transfer in the liquid phase. An approximate analytical method was developed to compute flow parameters such as velocity, pressure, and temperature profiles in the fluid system. (Abstract shortened by UMI.)