Performance analysis of grooved heat pipes using 3-D multi-channel thermal resistance network

2021-9
Sezmen, Ramazan Aykut
Heat pipes are phase change heat transfer devices that transfer high amounts of heat with low temperature differences compared to conventional cooling techniques due to their high thermal conductivity. Since heat pipes do not require any external power supply and not involve any moving parts, they are preferred for high reliability applications and in wide range of industrial applications from thermal management of electronics to space applications. Essentially, heat pipes use the advantage of occurring phase changes inside it and enable the movement of working fluid between its hot and cold ends. In the present study, thermal performance of flat grooved heat pipes (FGHP) for different design parameters and heat source and sink configurations are investigated. A three dimensional heat transfer model is developed using thermal resistance network analogy to simulate both conduction and phase change heat transfer. Coupled to thermal model, a one dimensional flow model is used to calculate change of radius of curvature and the velocity of the working fluid along the heat pipe’s longitudinal axis. Developed heat transfer and flow models are solved in a coupled way and an iterative solution procedure is followed until the energy and mass conservation are satisfied. Present three dimensional heat transfer model takes into consideration the lateral conduction heat transfer through the solid base material and allows to observe the effect of localized heat sources and sinks that do not entirely cover the width of FGHP. Crucial working parameters like wall temperatures all along the heat pipe, contact angle, vapor temperature and local hot spot regions are analyzed for local heat sources and sinks. Developed and validated models are used in a comprehensive study aiming to observe the effect of solid frame around the FGHP and in a parametric study investigating the effect of groove fin and width ratio for the same groove pitches.

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Citation Formats
R. A. Sezmen, “Performance analysis of grooved heat pipes using 3-D multi-channel thermal resistance network,” M.S. - Master of Science, Middle East Technical University, 2021.