Open AccessNumerical study on mixed convection in a horizontal flow past a square porous cavity using UNIFAES scheme
Author(s) -
Jorge Llagostera,
José Ricardo de Figueiredo
Publication year - 2000
Publication title -
revista brasileira de ciências mecânicas
Language(s) - English
Resource type - Journals
ISSN - 0100-7386
DOI - 10.1590/s0100-73862000000400008
Subject(s) - nusselt number , mechanics , rayleigh number , buoyancy , finite volume method , convection , combined forced and natural convection , porous medium , flow (mathematics) , quadratic equation , exponential function , materials science , natural convection , mathematics , thermodynamics , porosity , geometry , physics , mathematical analysis , reynolds number , turbulence , composite material
Mixed convection on the flow past a heated length and past a porous cavity located in a horizontal wall bounding a saturated porous medium is numerically simulated. The cavity is heated from below. The steady-state regime is studied for several intensities of the buoyancy effects due to temperature variations. The influences of Péclet and Rayleigh numbers on the flow pattern and the temperature distributions are examined. Local and global Nusselt numbers are reported for the heated surface. The convective-diffusive fluxes at the volume boundaries are represented using the UNIFAES, Unified Finite Approach Exponential-type Scheme, with the Power-Law approximation to reduce the computing time. The conditions established by Rivas for the quadratic order of accuracy of the central differencing to be maintained in irregular grids are shown to be extensible to other quadratic schemes, including UNIFAES, so that accuracy estimates could be obtained