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The Estimation of the Drag of Circular Cylinders at Subcritical Reynolds Numbers and Subsonic Speeds

Published online by Cambridge University Press:  04 July 2016

K. D. Thomson*
Affiliation:
Weapons Research Establishment, Department of Supply, Salisbury, South Australia

Extract

In an investigation, on the characteristics of the wake from slender cone-cylinders at large angles of attack, the strength and position of the vortices in the wake were determined for a large range of flow conditions. Two types of experiments were conducted, namely schlieren studies and wake traverses.

Schlieren photographs (such as Fig. 1) clearly reveal straight parallel vortex lines in the wake for subcritical values of the cross-flow Reynolds number component and for cross-flow components of the free stream Mach number up to at least 1·4. In ref. 1 numerous such schlieren photographs were analysed using the impulse flow analogy (refs. 2 and 3 for example). According to the analogy the progressive development of the wake along the body when viewed in cross-flow planes is similar to the growth with time of the flow behind a two-dimensional cylinder started impulsively from rest with the same cross-flow conditions.

Type
Technical Notes
Copyright
Copyright © Royal Aeronautical Society 1970 

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References

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