Study of mixed convection in a square enclosure with a rotating circular cylinder at different vertical locations

الملخص EN

Mixed convection in a square enclosure with a rotating circular cylinder located at different vertical locations is numerically studied.

The horizontal and vertical walls are kept at constant temperature Tc, while the surface of the rotating circular cylinder is maintained at a constant temperature Th.

A two dimensional solution for steady laminar mixed convection is obtained by solving governing equations in stream function-vorticity form with finite difference technique for different Richardson number (Ri = Gr / Re2) varying over the range of 0.0 to 10.

Depending on the Richardson number the convection phenomena inside the enclosure becomes natural, mixed, and forced convection.

For the first time this study goes to investigate the effect of changing the rotating circular cylinder positions along the vertical centerline on the fluid flow and heat transfer inside the enclosure.

The phenomena inside the enclosure is analyzed through a streamlines, isothermal patterns and average Nusselt numbers.

The results show that the flow field and temperature distribution inside the enclosure are strongly dependent on the Richardson numbers and the position of the rotating circular cylinder, and the enclosure has maximum heat transfer rate when the cylinder near the bottom wall (δ = 0.25).