FINITE-ELEMENT ANALYSIS OF 2-DIMENSIONAL AND 3-DIMENSIONAL FLOWS AROUND SQUARE COLUMNS IN TANDEM ARRANGEMENT

Two- (2D) and three-dimensional (3D) finite element analyses for flow around two square columns in tandem arrangement were performed with va rious column spacings and Reynolds numbers. The computed values were c ompared with the wind-tunnel results in terms of the aerodynamic chara cteristics of the leeward column. In most 2D computations, strong vort ices were formed behind the windward column, irrespective of widely ch anged Reynolds numbers. This was different from the experimental pheno mena of equivalent spacing, so that the computed time-averaged pressur e coefficients were not identical to the experimental values except wh en the distance between the two columns was adequately wide or narrow. On the other hand, in 3D computation, distinct differences in flow st ructures behind the column were observed between Reynolds numbers of 1 0(3) and 10(4) and the pressure coefficient in the 3D analysis with Re = 10(4) agreed well with the experimental value. Thus, the effectiven ess of 3D computations and Reynolds number effects on the flow around two square columns have been confirmed. (C) 1998 John Wiley & Sons, Lt d.