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A computational flow visualization study was made on the mixed fluid motions and thermal patterns of liquid mercury (Pr=0.02) contained within a horizontal slip ring annular region of radius ratio 2.6. Visualizations show that the liquid mercury were found to have points of maximum and minimum thermal plumes at the interior nodes, instead of the top and bottom nodes which is known for the air (Pr=0.7). For liquid mercury, when the inner cylinder is made to rotate, the thermal plume moves in a direction opposite to that of the rotation of the inner cylinder. This thermal plume movement is opposite to that observed for the high Prandtl number fluid flow where the mono-thermal plume on top of the inner cylinder moves in the same direction as the inner rotating cylinder.

Flow fields in the neighbourhood of constrictions in a tube were studied numerically. Flow seperation and reattachment as the flow passes through the constrictions in the tube were studied for Reynolds number to the order of 200. Constrictions with constriction spacing ratios of 1, 2, 3 and ∞ were studied for diameter constriction ratios of 0.2 to 0.6. Experimental flow visualizations were performed for similar double constrictions.

Numerical flow visualization was made on air contained in parallelogrammic thermal enclosures under various angles of gravitational fields for enclosure aspect ratio of 3.0. Rayleigh numbers considered are in the range of 103 to 106. The gravitational fields act on the enclosures in angles varying from 0° to 360° in steps of 15°. For air with a Prandtl number of 0.7, a transition in the mode of fluid circulation was observed when the gravitational field is varied and the mean Nusselt changed from maximum to minimum. Flow visualization experiments were made for air with Pr≅0.7 at Ra≅ 2x105 with aspect ratios of the order ≥ 1.