THERMAL SCIENCE

International Scientific Journal

TURBULENCE TRANSITION THRESHOLD OF A BUOYANCY-DRIVEN FLOW OVER AN ISOTHERMAL VERTICAL WALL

ABSTRACT
The integral formalism has been developped in an attempt to predict the mathematical transition threshold from laminar to turbulent regimes in a free convection boundary-layer flow adjacent to an isothermal vertical wall and also to gain a better understanding in the prediction of the turbulence mechanism. The transition threshold is approached herein as the intersection of the two fully developped laminar and turbulent flow regimes. The transition for the isothermal wall condition is Prandtl number dependent and occurs differently depending on whether the dynamical or thermal viewpoints are considered. A change in the transition threshold behaviour is observed at Pr=20.
KEYWORDS
PAPER SUBMITTED: 2014-03-25
PAPER REVISED: 2014-03-28
PAPER ACCEPTED: 2014-05-20
PUBLISHED ONLINE: 2014-06-15
DOI REFERENCE: https://doi.org/10.2298/TSCI140325064P
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2014, VOLUME 18, ISSUE Issue 4, PAGES [1063 - 1068]
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© 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