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The Influence of the Wake on the Flutter and Vibration of Rotor Blades*

Published online by Cambridge University Press:  07 June 2016

J. P. Jones
J. P. Jones*
Affiliation:
University of Southampton
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Summary

An approximate theory is described which takes into account the influence of the wake on the aerodynamic derivatives of an oscillating rotor blade. It is shown that the most important parameter is the number of cycles of the oscillation which occur during one revolution of the rotor. For integral values of this parameter the flexural damping is shown to become very small at small angles of incidence. The flutter characteristics of a simple rotor blade are calculated on the basis of this theory, and it is found that the wake causes radical changes in the critical speeds. The theory is in good qualitative agreement with experiment.

Type
Research Article
Information
Aeronautical Quarterly , Volume 9 , Issue 3 , August 1958 , pp. 258 - 286
Copyright
Copyright © Royal Aeronautical Society. 1958

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Footnotes

*

Tbe material in this paper is based on a report submitted to the Department of Scientific and Industrial Research in June 1954, which was later extended and circulated as A.R.C. Report 18,173, in January 1956. The present paper was received for The Aeronautical Quarterly in October 1957.

References

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