EXPERIMENTAL STUDY OF THE NATURAL CONVECTION HEAT TRANSFER FROM HORIZONTAL,INCLINED,AND VERTICAL HOLLOW PLATE AT CONSTANT HEAT FLUX

M.J. AL-AZAWI, SAAD

doi:10.37652/juaps.2007.15532

	EXPERIMENTAL STUDY OF THE NATURAL CONVECTION HEAT TRANSFER FROM HORIZONTAL,INCLINED,AND VERTICAL HOLLOW PLATE AT CONSTANT HEAT FLUX
Journal of University of Anbar for Pure Science
Article 24, Volume 1, Issue 1, 2007, Pages 123-133 PDF (570.15 K)
Document Type: Research Paper
DOI: 10.37652/juaps.2007.15532
Author
SAAD M.J. AL-AZAWI^*
Department of Mechanical Engineering - College of Engineering - University of Anbar
Abstract
Experimental investigation was carried out to study the effect of a hollow and inclination angles on the ability of a square flat plate squander the convective heat transfer. An experimental set-up of an uniformly heated Aluminum flat plate of a centerial hollow representing 0.25 of the entire surface area of the plate heated by a constant heat flux was used basically for this purpose. Experiments were performed for inclination angles of (0o,15o, 30o, 45o, 60o,75o, 90o)for a region of Rayleigh number between ( 151550-1616000).This study showed that the ability of the surface to dissipate heat was presented by the average Nusselt number as a function of Rayleigh number depending on the existence of the hollow and the inclination angle. The existing of the hollow increased the value of average Nusselt number up to (39%) in the horizontal state and change sequentially with the inclination angle and it reached the maximum value of (48%) at the angle (75o) and (22%) as a average for all the inclination angles under test as compared with the horizontal state of the present hollow surface and reached (59%) with the unhollow inclination surfaces.

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