CFD Modeling of Rayleigh-benard Convection in a Closed Rectangular Enclosure Presenting a Sinusoidal Floor
Oumar Drame *
Department of Physics, Faculty of Science and Technology, Fluid Mechanics Laboratory and Applications, Cheikh Anta Diop University of Dakar, Senegal.
Mariama N Koita
Department of Physics, Faculty of Science and Technology, Fluid Mechanics Laboratory and Applications, Cheikh Anta Diop University of Dakar, Senegal.
Abou Ndiaye
Department of Physics, Faculty of Science and Technology, Fluid Mechanics Laboratory and Applications, Cheikh Anta Diop University of Dakar, Senegal.
Cheikh Mbow
Department of Physics, Faculty of Science and Technology, Fluid Mechanics Laboratory and Applications, Cheikh Anta Diop University of Dakar, Senegal.
*Author to whom correspondence should be addressed.
Abstract
In this work, study of thermodynamic behavior of air in a closed rectangular enclosure is conducted presenting a sinusoid of amplitude 2a on the horizontal floor. The simulation was carried out in a steady state for Rayleigh numbers, 7x104 ≤ Ra ≤ 7x106 with the Prendtl’s number Pr = 0.71. Thus, to better demonstrate the influence of geometry on thermodynamic behavior, we carried out the study using different values of the aspect factor =2a/ with 2a and respectively the amplitude of the sinusoid and rectangle height. And in order to take into account the variation of density in the term of gravity in the equation of motion, we used the Boussinesq approximation. The results obtained from this simulation allowed us to present the isothermal lines, the streamlines and the mean of local Nusselt number. The results showed that the flow is affected by the variation of the aspect factor δ and for a fixed value of this factor, the increase in the Rayleigh number leads to a reorganization of the system which tends towards an ordered state.
Keywords: Sinusoïde, rayleigh-benard convection, boussinesq, approximation, CFD
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References
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