In this paper, we present a numerical study of natural convection in an inclined enclosure. This was achieved in order to stimulate the convective heat exchanges that occur over the absorber of solar air flat plate collector. The considered model is an inclined enclosure with adiabatic side walls and aspect ratios 1 ≤ AR ≤ 12, and which contain heated air-filled (Pr=0.71). The inclination angle Ө of the enclosure was varied from 00° to 90° with Rayleigh numbers in the range of 103 ≤ Ra ≤ 106 . The influences of Ө and Ra on the flow patterns are investigated. The analysis is carried out by a numerical solution of the full governing equations; the resolution of the problem is based on the finite volumes method employing a staggered grid arrangement by the iteratively SIMPLE-C algorithm.The results indicate that there was a strong effect of inclination angle on the flow mode transition
Natural Convection, Solar Air Flat Plate Collector, Inclined Enclosure, Flow Mode Transition, Flow Patterns
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