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Published 1990 | public
Journal Article

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

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.

Additional Information

© Springer-Verlag 1990. Received November 9, 1989. Dedicated to Prof. Dr.-lng. E. Berger on his 65th birthday. One of us (C.H. K. W.) would like to thank Professor Eberhard Berger and his student Michael Schumm (both of Technische Universität, Berlin) for some very enjoyable conversation and hospitality during a visit to Berlin in June 1989. It has also been a great pleasure indeed to communicate at length with Dr. Christoffer Norberg (of Chalmers University of Technology, Goteborg, Sweden) enabling a very useful discussion of methods and comparison of our data. Further thanks are due to lch Sugioka and Dr. Jeffrey Jacobs of Caltech for a great many discussions, to Rick Paniagua for construction of tiny parts necessary for the experiments, and lo Dr. Henning Rosemann for the "Übersicht". This work is supported by the U.S. Office of Naval Research, under contract N00014-84-K-0618.

Additional details

Created:
August 19, 2023
Modified:
October 18, 2023