The effect of a wake splitter plate on the flow amound a circular cylinder.

Experiments were carried out using a circular model with a wake splitter plate having length ratio (L/d)=1/6, 1 or 3 in the Reynolds number range of 5×104≤Re≤107 using a cryogenic wind tunnel. The resulting variations of pressure distributions, drag coefficients, back pressure coefficients, the minimum values of pressure coefficients and Strouhal numbers with the length of wake splitter plate are presented. The effect of the wake splitter plate on the drag and Strouhal number are shown to change depending on the Reynolds number range and on the length of the wake splitter plate. Effects of the wake splitter plate on the reduction of the drag coefficient is most remarkable in the subcritical Reynolds number range. In the supercritical Reynolds number range the wake splitter plate serves to suppress the separation bubble. In the transcritical Reynolds number range the effects of the wake splitter plate can hardly be recognized.