Development of a cfd assisted 3-d modeling and analysis methodology for grooved heat pipe design and performance assessment

2020-10-13
Gökçe, Gökay
Although the idea of phase change heat transfer has a long history going back to mid 19th century, modeling of multi-phase heat transfer still draws interest from the engineers and scientists worldwide due to its complex nature. Taking advantage of phase-change heat transfer, heat pipes have been used effectively in numerous industrial applications for thermal management of electronic components due to their tremendous advantages. However, multi-dimensional modeling of heat pipes is a challenging task, requiring a physically based mathematical model to address evaporation, condensation and free surface flow phenomena. Although several studies about the flat groove heat pipes are available in the literature, these studies do not address complex groove shapes due to the modeling approach, manufacturing limitations and absence of skin friction correlations for a specific geometry. Nowadays, due to the improvements in simulation technology, more engineering questions can be answered realistically with computers in a virtual environment. However, commercial software are not developed to meet the specific needs to simulate individual problems, especially when sophisv ticated physical phenomena such as phase change with free surface flow inside the channel is involved. Neither commercial nor academic CFD program that can simulate the flow and heat transfer characteristics of a grooved heat pipe in one step is currently available. To address this, an analysis methodology that computes the liquid flow and heat transfer inside a grooved heat pipe is developed which simultaneously uses a commercial CFD program (Fluent®) along with Python® programming language. With the developed methodology, the effect of various groove models on the heat pipe performance are investigated. The results show that it is possible to design heat pipes with increased performance both in terms of higher heat carrying capacity, and lower peak temperatures with a judicious selection of groove geometry.

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Citation Formats
G. Gökçe, “Development of a cfd assisted 3-d modeling and analysis methodology for grooved heat pipe design and performance assessment,” Ph.D. - Doctoral Program, Middle East Technical University, 2020.