Numerical Study of Natural Convection in a Square Cavity Filled with a Porous Medium Saturated with Nanofluid

Abstract

Steady state natural convection of Al₂O₃-water nanofluid inside a square cavity filled with a porous medium is investigated numerically. The temperatures of the two side walls of the cavity are maintained at T_H and T_C, where T_C has been considered as the reference condition. The top and the bottom horizontal walls have been considered to be insulated i.e., non-conducting and impermeable to mass transfer. Darcy–Forchheimer model is used to simulate the momentum transfer in the porous medium. The transport equations are solved numerically with finite volume approach using SIMPLER algorithm. The numerical procedure is adopted in the present study yields consistent performance over a wide range of parameters (Rayleigh number, Ra, 10⁴≤ Ra≤ 10⁶, Darcy number, Da, 10^-5≤ Da ≤ 10^-3, and solid volume fraction, j, 0.0 ≤ j ≤ 0.1). Numerical results are presented in terms of streamlines, isotherms and average Nusselt number. It was found that heat transfer increases with increasing of both Rayleigh number and Darcy number. It is further observed that the heat transfer in the cavity is improved with the increasing of solid volume fraction parameter of nanofluids.