Mixed convention around a heated rotating horizontal square cylinder in a circular enclosure

Numerical results are presented for two-dimensional laminar mixed convection flows around a heated horizontal square cylinder rotating slowly within a concentric circular enclosure. The time evolution of the rotation and buoyancy-induced mixed convection flows are analyzed over a range of the radius ratio χ, the Gr, and the rotational Re. The radius ratio considered ranged from 0.2 to 0.55. The Gr range is taken from 103 to 2×104, and the rotational Re varied from 0 to 24. The flow and temperature fields and heat transfer characteristics are presented over this parameter range. The effect of the rotating noncircular geometry of the inner cylinder on the flow field and the heat transfer characteristics are considered in detail and compared with those previously studied for differentially heated concentric circular annuli.