Laminar Mixed Convection of Cold Water in a Vertical Annulus With a Heated Rotating Inner Cylinder

A numerical investigation is made to evaluate the perturbing effect of forced convection due to axial rotation of the inner cylinder on natural convection heat transfer of cold water with density inversion effects in a vertical cylindrical annulus. The mixed convection heat and fluid flow structures in the annulus are found to be strongly affected by the density inversion effects. The centrifugally forced convection can result in significant enhancement of the buoyant convection heat transfer of cold water with the density inversion parameter being equal to 0.4 or 0.5; thus the slow axial rotation of the inner cylinder can be a viable means for heat transfer augmentation of cold water natural convection in a vertical annulus.