We study unsteady natural convection in an enclosure bounded by a horizontal plane and a differentially heated elliptical wall. Using a conformal transformation, the curvilinear domain is reduced to a rectangular cross-section domain. The formulated transfer equations are integrated using the finite volume method. The discretized equations are solved using the Thomas algorithm combined with a line-by-line iterative Gauss-Seidel scheme. Numerical simulations show that over time the system passes through successive states of equilibrium before reaching a steady state characterized by a mean temperature difference in the vicinity of 0.32 for all considered Rayleigh numbers.

elliptic-cylindrical coordinate system, finite volume method, isotherms, relaxation, streamlines, unsteady natural convection.

Received: February 25, 2023; Accepted: April 19, 2023; Published: May 13, 2023

How to cite this article: Fadel DIOP, Alpha Malick NDIAYE, Samba DIA and Cheikh MBOW, Natural unsteady thermal convection in a space between an elliptical plate and horizontal plane, Advances and Applications in Fluid Mechanics 30(1) (2023), 83-105. http://dx.doi.org/10.17654/0973468623005

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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