THERMAL SCIENCE

International Scientific Journal

Hamza Ali Agha

,

Nadir Boutalbi

,

Soufiane Rahal

INFLUENCE OF THERMAL DISPERSION AND VARIABLE VISCOSITY ON MIXED CONVECTION FLOW IN NON-DARCY POROUS MEDIUM FILLED BY NANOLIQUID

ABSTRACT
In this current paper, a numerical analysis was performed to study the effects of variable viscosity and thermal dispersion considered for an Ergun-Darcy mixed convection flow on a heated horizontal plate from below by variable heat flux in a saturated porous medium filled with Tiwari and Das nanoliquid. The governing partial differential equations are transformed into coupled nonlinear ordinary differential equations using an appropriate similarity transformation and the resulting system of equations is then solved numerically by efficient finite-difference method. Numerical results are presented to illustrate how the physical parameters affect the flow field, temperature and concentration. Moreover, the interesting features of the solutions in terms of the number of Nusselt are presented graphically.
KEYWORDS
mixed convection, thermal dispersion, non-Darcy porous medium, variable viscosity, nanofluid
PAPER SUBMITTED: 2025-08-15
PAPER REVISED: 2026-05-20
PAPER ACCEPTED: 2026-06-01
PUBLISHED ONLINE: 2026-08-07
DOI REFERENCE: https://doi.org/10.2298/TSCI250815156A
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Influence of thermal dispersion and variable viscosity on mixed convection flow in non-Darcy porous medium filled by nanoliquid

© 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 4.0 International licence