THERMAL SCIENCE

International Scientific Journal

Mingzheng Ye

,

Xian Yang

,

Jin Wang

,

Milan Vujanović

,

Bengt Sundén

EFFECTS OF ELASTIC PILLARS ON FLUID-FLOW AND HEAT TRANSFER ENHANCEMENT IN A MICRO-CHANNEL

ABSTRACT
In this paper, periodic vortices are generated by a fluid passing a cylindrical obstacle, d, near the micro-channel inlet. Two elastic pillars are arranged on the walls, and the effect of the pillar spacing on heat transfer performance is studied using the Arbitrary Lagrangian-Euler method. With the spacing of 10d, the small pillar amplitude of 2 μm is not conducive to the generation of vortices. The flexible vortex generator has higher heat transfer efficiency and lower pressure loss than the rigid vortex generator. The two pillars with no spacing generate isolated vortices, and the mixing of these vortices is insufficient downstream the pillars. It is found that with the pillar spacing of 5d, the overall performance factor is significantly higher than that with the pillar spacing of 0d and 10d in the Reynolds number range of 800 to 1100. The average Nusselt number with the spacing of 5d increases by 19.2% compared to that with the spacing of 0d at the Reynolds number of 1000. When the Reynolds number is 1100, the overall performance factor is 43% higher than that with a single rigid pillar. The vortices are periodically generated by the two pillars with the 5d spacing, and the disturbance to the boundary layer enhances the heat transfer downstream the region in the micro-channel.
KEYWORDS
Heat Transfer Enhancement, microchannel, fluid-structure interaction, flexible vortex generator, Dynamic mesh
PAPER SUBMITTED: 2022-06-17
PAPER REVISED: 2022-08-16
PAPER ACCEPTED: 2022-08-18
PUBLISHED ONLINE: 2022-09-10
DOI REFERENCE: https://doi.org/10.2298/TSCI220617139Y
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2023, VOLUME 27, ISSUE Issue 1, PAGES [275 - 287]
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Effects of elastic pillars on fluid-flow and heat transfer enhancement in a micro-channel

© 2024 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