The rotor blades on any helicopter are usally never identical in real life, however, most helicopter aeroelastic stability analyses assume the blades are identical. There is a need to examine this realistic problem of how blade-to-blade dissimilarities modify helicopter aeromechanical stability and hub loads. The effects of blade-to-blade dissimilarities, such unbalance in blade mass, and dissimilarities in blade stiffness and aerodynamics are examined systematically. The results are discussed quantitatively and qualitatively. A study on blade dissimilarity is carried out using a finite element analysis that includes rotor aerodynamics, elastic blade deformations, and body pitch and roll motions. Results show that dissimilarity in blades inplane stiffness improves the regressing lag stability, but with some increase in rotor side forces harmonics and 1/rev torque load. Dissimilarity in flap stiffness has little effect on aeromechanical stability and hub loads. Dissimilarities in blades mass and lift do not affect aeromechanical stability, but severely increase hub loads.

17th European Rotorcraft Forum 1991, Berlin

Conference Paper

englisch

21,0 x 29,7 cm, 11 Seiten

DGLR-Bericht, 1991, 1991-08, 17th European Rotorcraft Forum Proceedings; 1991; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

Dieser Aufsatz ist nicht Teil der Veröffentlichung!

rotor blades, aerodynamics, helicopters

Bestellbar

1991