The Natural Convection in Annular Space Located Between Two Horizontal Eccentric Cylinders: The Grashof Number Effect

The natural convection in an annular space, located between two horizontal eccentric cylinders is studied. This latter is oriented at an arbitrary angle α. The annular space is filled by a Newtonian and incompressible fluid. The number of Prandtl is fixed at 0.702 (case of the air), the eccentricity is fixed at 0.4 but the number of Grashof varies. By using the approximation of Boussinesq and the vorticity-stream function formulation, the flow is modeled by the differential equations with the derivative partial. For the conditions of heating, we suppose the two cylindrical walls of the enclosure isotherms, T1 for the internal wall and T2 for the external wall, with T1>T2.A computer code was developed, the latter uses finite volumes, for the discretization of the equations and in order to show its reliability. We examine the effect of the number of Grashof on the results obtained that it is qualitatively or quantitatively.