Laminar and turbulent natural convection in the annulus between horizontal concentric cylinders

Numerical solutions are presented for the steady-state, two-dimensional natural convection in the annulus between two horizontal concentric cylinders which are held at different constant temperatures. Solutions for the laminar case are obtained up to Rayleigh number (based on gap width, L) of 10 to the 5th. Turbulent flow results are presented for the Rayleigh number range of 10 to the 6th - 10 to the 7th, the k-epsilon turbulence model has been applied to obtain the results. Buoyancy effects on the turbulence structure are also accounted for. The results for both the laminar and turbulent cases are in good agreement with available experimental data and other solutions in the literature. All results presented are for the outer cylinder diameter to inner cylinder diameter ratio of 2.6.