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THERMAL SCIENCE
International Scientific Journal
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NUMERICAL INVESTIGATION OF EFFECT OF FILL RATIO AND INCLINATION ANGLE ON A U-SHAPED ELLIPTICAL GRAVITY HEAT PIPE THERMAL PERFORMANCE
ABSTRACT
As electronic devices become increasingly compact, effective thermal management is crucial for performance. This study establishes a model of a U-shaped elliptical gravity heat pipe with dual heating ends and a single cooling end. Through CFD simulations, the impacts of filling ratio and inclination angle on the thermal transfer capacity for the heat pipe were investigated. The results indicate that the evaporator surface temperature and thermal resistance of the heat pipe initially decrease and then increase with an increasing filling ratio. Within the inclination range of 10° to 90°, the evaporator surface temperature and thermal resistance gradually decrease. The optimal filling ratio is found to be 65%, and the optimal inclination angle is 90°. Furthermore, it was observed that higher heat input intensifies the effects of filling ratio and inclination angle affecting heat pipe thermal performance. These findings highlight the critical role of these parameters in optimizing heat pipe performance under varying heat inputs.
KEYWORDS
PAPER SUBMITTED: 2024-11-13
PAPER REVISED: 2024-12-21
PAPER ACCEPTED: 2024-12-26
PUBLISHED ONLINE: 2025-02-16
DOI REFERENCE: https://doi.org/10.2298/TSCI241113023C
CITATION EXPORT: view in browser or download as text file
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© 2026 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence