Natural Convection Coupled with Radiation Heat Transfer in Slanted Square and Shallow Enclosures Containing an Isotropic Scattering Medium

Abstract

A finite-volume method (FVM) is used to address combined heat transfer, natural convection, and volumetric radiation with an isotropic scattering medium, in a tilted shallow enclosure. Numerical simulations are performed in the in-house fluid flow software GTEA. All the results obtained by the present FVM agree very well with the numerical solutions in the references. The effects of various influencing parameters such as the Planck number (0.0001 Pl 10), the scattering albedo (0 x 1), the inclination angle (À60 a 90 ), and aspect ratio (1 AR 5) on flow and heat transfer have been numerically studied. For a constant Pl number, flow is slightly intensified at the midplane as the Ra number increases from 10 6 to 5 Â 10 6 . As the scattering albedo increases, the effect of radiation heat transfer decreases on both slanted and horizontal enclosures. In positive tilt angles, the influence of a on heat transfer is quite remarkable. The highest Nu rad appears at a ¼ 30 (x ¼ 1)and 0 (x ¼ 0, 0.5), whereas Nu rad is maximum at a ¼ À 15 (x ¼ 1) and À45 (x ¼ 0, 0.5). At a ¼ À15 , the maximum and minimum values of Nu rad are presented for x ¼ 0, AR ¼ 1 and x ¼ 1, AR ¼ 5.

Effects of Semitransparent Window AspectRatio on Interaction of Collimated Beam withNatural Convection: Part I

“…The extinction coefficient had a pronounced effect on the temperature distributions. A coupled numerical investigation on natural convection with volumetric radiation with gray and isotropic scattering medium in two-dimensional rectangular cavity were analysed for Planck numbers, scattering albedo of the medium for various tilt angles and the aspect ratios of the cavity in [14]. They observed that emissivity of the horizontal wall and the scattering albedo have significant effect on the flow and temperature patterns.…”