Session: 10-01 Interactive Presentations

Paper Number: 97307

97307 - Numerical Prediction of Visualization and Temperature Distribution of Two Phase Closed Thermosyphon With Openfoam 

In our era in which the energy transition from the fossil fuel energy to the green energy is in the progress, the importance of energy regeneration has been recognized. High carbon dioxide emission using excessive fossil fuel has led to not only environmental pollution but accelerated global warming which threatens human beings. To solve foresaid problems, energy transition becomes more crucial. However, it has been getting difficult to convince the energy transition plan links to the Paris Agreement owing to the lack of relevant green energy technologies. In this situation, the energy regeneration technology has been received considerable attention in many applications such as thermoelectric device, piezoelectric device, waste heat recovery etc. due to its ability of reducing carbon dioxide level by enhancing the efficiency.

The waste heat recovery system is one of the most widely adopted green energy technology spanning from light facility as apartment to a heavy facility as power plant owing to its large energy storage efficiency while easiness to apply. The waste heat recovery is conducted by the heat exchanger in general. Development of TPCT (Two-Phase Closed Thermosyphon) heat exchanger which takes advantage of latent heat by utilizing evaporation & condensation phenomena provides enhanced heat transfer efficiency compared to that of conventional heat exchangers based on single phase heat transfer. However, most relevant studies for TPCT have been conducted experimentally despite its high cost since low predictive accuracy of computational model for phase change process with expensive computational costs.

In this work, we conducted numerical simulation with phase change process to predict thermal performance of TPCT.  A suggested phase change model with accounting vapor density and saturation temperature changes is considered to provide enhanced predictive accuracy of phase change process. The numerical result was validated with the experimental study conducted with an identical geometry and boundary conditions used in the study. In addition, the effect of mass transfer intensity factor in phase change model was extensively investigated to relate with thermal performance and fluid visualization in TPCT.

Presenting Author: Sehyeon Cho Chung-ang university