THERMAL SCIENCE

International Scientific Journal

Hassnia Hajji

,

Lioua Kolsi

,

Faouzi Askri

,

Chemseddine Maatki

,

Walid Hassen

,

Mohamed Naceur Borjini

HEAT TRANSFER AND FLOW STRUCTURE THROUGH A BACKWARD AND FORWARD-FACING STEP MICRO-CHANNELS EQUIPPED WITH OBSTACLES

ABSTRACT
This study presents 2-D simulations of a flow-through a sudden expansion/contraction micro-channel with the existence of obstacles. The bottom wall is maintained at constant flux, while the other walls are adiabatic. Rectangular adiabatic obstacles are mounted before the expansion region on the upper and lower wall of the channel used. The finite element method was used to discretize the equations that govern the physical model. Results indicate the apparition of a separate vortex, situated in the corner after the sudden expansion of the micro-channel for low Reynolds numbers. For higher values and expansion ratios, the vortex separation length increases. The obtained results show that the obstacles have a considerable effect on the dynamics of the flow and enhancement of heat transfer.
KEYWORDS
sudden expansion/contraction, microchannel, Reynolds number, nusselt number
PAPER SUBMITTED: 2020-02-15
PAPER REVISED: 2020-06-23
PAPER ACCEPTED: 2020-07-16
PUBLISHED ONLINE: 2020-08-08
DOI REFERENCE: https://doi.org/10.2298/TSCI200215219H
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2021, VOLUME 25, ISSUE Issue 4, PAGES [2483 - 2492]
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Heat transfer and flow structure through a backward and forward-facing step micro-channels equipped with obstacles

© 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