Document Type : Research Paper

Author

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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