Investigation of the effect of design parameters on vapor chamber heat transfer characteristic

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2022-11-25

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Karakaya, İrem

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In this study, a detailed two-phase computational modeling of a vapor chamber is performed. A code written in MATLAB is used to accurately simulate the phase-change process within the wick structure. Conservation of mass is satisfied by matching the evaporated and condensed fluid mass flow rates. Secant Method is used to find vapor temperature. The current model is validated and then, wall temperature, pressure, and mass flow rate distributions of the working fluid are calculated and plotted. Parametric study is performed to see the effects of operating and design parameters on the vapor chamber heat transfer and fluid flow characteristics. In this parametric study, porosity, wick and wall thicknesses, wall material, different working fluid, and material types are investigated. According to the specifications of the design, the dry-out condition is evaluated through a comparison of the liquid pressure drop and the capillary pressure head. It is examined if the maximum system temperature exceeds the maximum allowable temperature. Parametric results show that in order to achieve the desired conditions of a lower temperature drop in the system and a higher dryout heat flux condition, the best vapor chamber design parameter set for given design conditions in the current study, consists of copper-water as a working fluid and material couple, smaller porosity (0.45), smaller wick thickness (0.12 mm), and larger wall thickness (0.25 mm). The current vapor chamber model enables to specify the parameters to design a vapor chamber.

Subject Keywords

Vapor chamber, Wick, Two-phase cooling, Electronics cooling, Phase-change modeling

URI

https://hdl.handle.net/11511/101183

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

İ. Karakaya, “Investigation of the effect of design parameters on vapor chamber heat transfer characteristic,” M.S. - Master of Science, Middle East Technical University, 2022.