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Modelling and vibration of composite thin-walled rotating blades featuring extension-twist elastic coupling

Published online by Cambridge University Press:  03 February 2016

S-Y. Oh
Affiliation:
Department of Engineering Science and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
L. Librescu
Affiliation:
Department of Engineering Science and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
O. Song
Affiliation:
Department of Mechanical Engineering, Chungnam National University, Daejon City, South Korea

Abstract

The modelling and vibration of composite thin-walled pre-twisted rotating blades of non-uniform cross-sections along their span, and featuring the extension-twist elastic coupling are addressed. To this end, Hamilton’s principle is used to derive the equations of motion and the associated boundary conditions. In addition to the pretwist and warping restraint, the exotic properties of advanced composite material are used, and the efficiency of implementing the tailoring technique toward the enhancement, without weight penalties, of the vibratory behaviour of rotating blades is illustrated. Comparisons between the predictions by both Wagner’s and Washizu’s approaches are presented, and pertinent conclusions regarding the implications of the various geometrical and physical characteristics of the blade are outlined.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2005 

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