Analysis of stall flutter of a helicopter rotor blade.A study of rotor blade aeroelastic stability was carried out, using an analytic model of a two-dimensional airfoil undergoing dynamic stall and on elastomechanical representation including flapping, flapwise bending and torsional degrees of freedom. Results for a hovering rotor demonstrated that the models used are capable of reproducing both classical and stall flutter. The minimum rotor speed for the occurrence of stall flutter in hover was found to be determined from coupling between torsion and flapping. Instabilities analogous to both classical and stall flutter were found to occur in forward flight. However, the large stall-related torsional oscillations which commonly limit aircraft forward speed appear to be the response to rapid changes in aerodynamic moment which accompany stall and unstall, rather than the result of an aeroelastic instability.
Document ID
19730040730
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Crimi, P. (Avco Corp. Avco Systems Div., Wilmington, Mass., United States)
Date Acquired
August 7, 2013
Publication Date
March 1, 1973
Subject Category
Aircraft
Report/Patent Number
AIAA PAPER 73-403
Meeting Information
Meeting: Structures, Structural Dynamics, and Materials Conference