Early development of unsteady convective laminar flow in an inclined channel using CFD: Application to PV panels

Abstract The aim of this study is to investigate the heat transfer and flow dynamics in inclined PV panels. For this purpose, a numerical study of the early stage regime of natural convection flow in an inclined plane channel asymmetrically heated at a 510 W/m 2 uniform heat flux, corresponding to the average annual solar heat flux in France, has been performed. Numerical simulations are presented for two-dimensional, laminar and unsteady flow using the finite volume approach. The results showed appearance of large-scale flow instabilities which will develop and propagate until the development of a pocket-like vortex (reversed flow). Moreover, for large channel inclination angles (α = +20° and α = −20° with regard to the vertical position) the heat transfer rate is shown to be low. The maximal increase and decrease in mass flow rate are 7% for α = −20° and 21% for α = +20° respectively, compared to that of vertical channel.

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