... number in the case of a proous cylindrical annulus. Two cases of isothermal and convective boundary conditions are considered. The Nusselt number is always found to increase with radius ratio and Rayleigh number. It exhibits a maximum when the aspect ratio is around unity; maximum shifts towards lesser...

..., the numerical results are in good agreement with the experimental data. Multi-cellular regimes and hysteresis loops have also been reported in the literature for fluid annuli but some differences between the two cases exist and are fully explained below. KEY WORDS Natural convection Cylindrical annulus Porous...

...V.K. GARG; A.Z. SZERI This numerical study of natural convection flow in a horizontal cylindrical annulus is aimed at establishing the utility of the Galerkin‐spline formulation for natural convection problems. The annulus has isothermal walls and the fluid is of constant material properties except...