Measurements of base pressure in the wake of a cylinder at low Reynolds numbers

TLDR: In this article, it was shown that the level of base suction is affected in only a minor fashion by whether parallel or oblique shedding is present, and it was found that the data are independent of the base pressure hole sizes and cylinder diameters that were used.

Abstract: Measurements have been made of the base pressure coefficients of long circular cylinders at low Reynolds numbers from 35 to 1100 in a cross flow. The variation of "base suction" (negative base pressure coefficient or - C_(pb)) with Reynolds number shows a remarkably good correspondence with the variation of the Strouhal number. It is also possible to relate the variation in suction with the physical modes of wake formation found in previous studies. It is shown that the level of base suction is affected in only a minor fashion by whether parallel or oblique shedding is present, and it is found that the data are independent of the base pressure hole sizes and cylinder diameters that were used. The base suction is essentially constant along the span of a cylinder (outside of regions extending about 20 diameters in from each end), and the results arc independent of cylinder aspect ratio (L/D) provided that one exceeds a critical value of L/D.