Numerical Study of Convective Heat Transfer from Two Identical Square Cylinders Submerged in a Uniform Cross Flow

Abstract

This article presents numerical results of convective heat transfer from two identical square cylinders (TISC) arranged at close proximity in a uniform cross flow of air (Pr = 0.71) at the particular Reynolds number of 250. The proximity arrangement of the TISC is defined by longitudinal spacing ranging from zero to unity, with the transverse spacing ranging from 0.125 to unity. Results are obtained by the finite-difference method for 25 cases, divided into five groups for convenience of discussion. It is found that the time-averaged or mean convective heat transfer rates from the TISC reach their maxima when the transverse spacing value is about 0.3 from the view of the group averaging at a given transverse spacing. The heat transfer rates from inner faces of the TISC are generally greater than those of the outer sides, by a factor of about 2 to 3. Depending on the TISC arrangement, a bifurcation sometimes occurs, with the bifurcated lower St value corresponding to the shedding from the outer shear layer, and the higher one corresponding to the shedding from the inner shear layer. The significant effect of the TISC arrangement on the flow-induced forces is also reported and discussed.