Effect of opposing buoyancy on two-dimensional laminar flow and heat transfer across a confined circular cylinder
Keywords:opposing buoyancy, Richardson number, drag coefficient, Nusselt number, steady regime, vortex.
This research examines the effect of opposing thermal buoyancy on momentum and heat transfer characteristics of a confined cylinder submerged in Newtonian fluid. The detailed flow and temperature field are shown in term of streamlines and isotherm contours. The numerical investigation are done for the range of conditions as Re = 5 to 40, Richardson number Ri = -0.1 to -4, Pr = 1, and blockage ratio β = 0.2. When the buoyancy is opposed, it is depicted that the flow separation becomes asymmetrically and diminishes gradually and at some critical value of Richardson number it totally disappears resulting a creeping flow. Two rotating regions appear under the cylinder and behind the cylinder under the upper channel wall. Moreover, the total drag coefficient and the average Nusselt number are calculated.