Abstract

Using a bi-cylindrical coordinates system and a vorticity-stream function formulation, the authors study numerically the two dimensional unsteady natural convection of a Newtonian fluid bounded by portions of cylinders. A spatial discretization based on the finite difference method is used to approximate the dimensionless equations. While a purely implicit scheme is adopted for the time discretization. The algebraic systems of equations resulting from the discretization are solved by a Successive under Relaxation (SUR) method. The authors analyzed the effects of the Rayleigh number on the dynamic of the system. The analysis of the thermal and flow field showed that for Rayleigh number greater than 5.106 the transfers inside the enclosure are dominated by convection.

Keywords:

Bi-cylindrical coordinates, convection, flow, fluid, heat transfer,

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Competing interests

The authors have no competing interests.

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The authors have no competing interests.