EFFECT OF WEAK ROTATION ON NATURAL-CONVECTION IN A HORIZONTAL POROUS CYLINDER

Natural convection in a fluid saturated porous medium confined in a ho rizontal circular cylinder and rotating about its axis, with isotherma l boundary conditions and uniform internal heat sink, is studied by bo th numerical and perturbation methods. No symmetry with respect to the vertical diameter is expected for the flow and temperature fields and the whole region must be involved in the computation. Only the weak r otation regime, for which the centrifugal force is negligible compared to gravity, is considered. Governing equations for the two-dimensiona l flow field are solved in both rotating and non-rotating coordinate s ystems. Results indicate that rotation significantly decreases the rad ial amplitude of fluid particle trajectories in the radial direction a nd thus reduces the overall heat transfer.