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Vibration Characteristics of Pre-twisted Blades of Asymmetrical Aerofoil Cross-Section

Published online by Cambridge University Press:  07 June 2016

W. Carnegie  and
B. Dawson
W. Carnegie
Affiliation:
University of Surrey
B. Dawson
Affiliation:
University of Surrey
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Summary

The natural frequencies and mode shapes of vibration of cantilever aerofoil cross-section blades of pre-twist angle in the range 0 to 90 degrees are obtained. The beams are 152·4 mm long and the width / thickness ratio is such that they may be regarded as slender. Theoretical frequency ratios and mode shapes of vibration, neglecting shear and rotary inertia effects, are obtained for two sets of beams, one with clockwise pre-twist relative to the root cross-section and the other with anti-clockwise pre-twist. The effect of variation in the value of the centre-of-flexure coordinates upon the natural frequency ratios and mode shapes of vibration is investigated. The theoretical results are compared to corresponding experimental results.

Type
Research Article
Information
Aeronautical Quarterly , Volume 22 , Issue 3 , August 1971 , pp. 257 - 273
Copyright
Copyright © Royal Aeronautical Society. 1971

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References

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