Laminar Natural Convection Study in a Horizontal Half-Elliptical Enclosure Using Heater on Horizontal Wall

Abdelkarim Bouras; Djedid Taloub; Abdelhadi Beghidja; Zied Driss

Authors

Abdelkarim Bouras Department of Physics, Faculty of Sciences, University MohamedBoudiaf of M’sila, M’sila, Algeria
Djedid Taloub Department of Physics, Faculty of Sciences, University MohamedBoudiaf of M’sila, M’sila, Algeria
Abdelhadi Beghidja Laboratory of Renewable Energy and Sustainable Development (LRESD), University brothers Mentouri Constantine1, Algeria
Zied Driss Laboratory of Electromechanical Systems (LASEM), National School of Engineers of Sfax (ENIS), University of Sfax,Sfax, Tunisia

Abstract

A numerical analysis of laminar natural convection in a horizontal annulus between an internal heated plane and an external cold half-elliptical was investigated using approximation of Boussinesq. Both internal and external walls are maintained at the constant temperature and air is the working fluid. Numerical solutions are obtained using a commercial computational fluid dynamics package, FLUENT, using the finite volume method. Effects of the Rayleigh number, Rat, on the Nusselt number, Nu, as well as velocity and temperature fields are investigated for the range of Ratfrom 1.0 103 to 5.0 105. The results show that for a small thermal Rayleigh number, the heat transfer within the annulus is essentially controlled by the conduction process. As the thermal Rayleigh number increases (Rat≥104), the role of convection becomespredominant. Alsothe heat transfer rate increases. Theaim of this study is to observethe effects of thermal Rayleigh numberon the structure of the flow and the distribution of the temperature.