## THERMAL SCIENCE

International Scientific Journal

### EFFECT OF THERMAL RADIATION ON NATURAL CONVECTION IN A SQUARE POROUS CAVITY FILLED WITH A FLUID OF TEMPERATURE-DEPENDENT VISCOSITY

**ABSTRACT**

A numerical study of the natural convection combined with thermal radiation inside a square porous cavity filled with a fluid of temperature-dependent viscosity is carried out. The side horizontal walls are assumed to be adiabatic while both the left and right vertical walls are kept at constant but different temperatures. The Rosseland diffusion approximation is used to describe the radiative heat flux in the energy equation. The governing equations formulated in dimensionless stream function, vorticity, and temperature variables are solved using finite difference method. A parametric analysis illustrating the effects of the radiation parameter (0 ≤ Rd ≤ 10), Darcy number (10–5 ≤ Da ≤ 10–2), and viscosity variation parameter (0 ≤ C ≤ 6) on fluid flow and heat transfer is implemented. The results show an essential intensification of convective flow with an increase in the radiation parameter.

**KEYWORDS**

PAPER SUBMITTED: 2015-07-22

PAPER REVISED: 2016-06-26

PAPER ACCEPTED: 2016-06-28

PUBLISHED ONLINE: 2016-08-07

**THERMAL SCIENCE** YEAR

**2018**, VOLUME

**22**, ISSUE

**Issue 1**, PAGES [391 - 399]

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