Combination of CFD and DOE for optimization of thermosyphon heat pipe

A heat pipe, which contains evaporator, adiabatic, and condenser, is a simple device with proper heat transfer rate and a little heat loss, without any moving parts. In this study, the effects of length of the three mentioned sections of heat pipe were investigated through introducing the ratio of adiabatic length to the condenser length or evaporator length as aspect ratio (AR), filling ratio of working fluid, and heat load on the thermal performance of a thermosyphon heat pipe by combining computational fluid dynamics (CFD) and design of experiment (DOE). Optimum conditions were obtained using DOE. Prior to determining the optimum conditions, the heat pipe was simulated using volume of fluid model through solving the governing equations of mass, momentum, and energy for evaporation and condensation phenomena by finite volume method. The results were confirmed by comparing the 2D CFD simulation results with the experimental data. The purpose of this research was to find the optimal lengths of different parts. The results showed that the averaged optimum values for the above mentioned parameters (AR, heat load, and filling ratio) were 0.8325, 246 W, and 85%, respectively. In total, thermal performance of the heat pipe was improved for lower adiabatic zone length and higher values of heat load and filling ratio.

Automated summary

By investigating the effects of length of different sections of a heat pipe on thermal performance and optimizing through computational fluid dynamics and design of experiment, it was found that shorter adiabatic zone length and higher heat load and filling ratio contribute to improving thermal performance of the heat pipe.