Document Type : Article

**Authors**

Mechanical Engineering Department, Engineering College, University of Basrah, Basrah, Iraq

**Abstract**

This paper investigates the double–diffusive natural convection in partially layered square cavity. The cavity composed of porous layer on the left and fluid layer on the right. A conductive solid body is included inside the cavity to control the natural convection. The left wall is kept at constant high temperature and adjusted with high concentration, while the right wall is kept at low temperature and low concentration. The horizontal walls are thermally insulated. The 2-dimensional governing equations have been solved using up-wind scheme finite difference method. The Parndtl number and buoyancy ratio are fixed at 6.26 and 1, respectively. The problem has been governed by five parameters namely, Lewis number (Le = 1–50), Rayleigh number Ra (10^{3}-10^{6}), Darcy number (10^{-9}-1), aspect ratio of the body relative to the cavity *A* (0.3, 0.5) and the position of the body. The results have showed that locating the solid body close to the mid height of the left wall gives maximum convective heat transfer, while minimum heat transfer is associated when the solid body is located at the cavity center. It is also found that the Nusselt and Sherwood numbers behave contradictory with the location of the solid body.

**Keywords**

**Main Subjects**

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