This paper reports on the effectiveness of employing Duffing type nonlinear stiffness in limiting rotor blade lead/lag motion and reducing susceptibility to ground and air resonance. Classic instability on isotropic supports is stabilized in limit cycle response at amplitudes sufficiently low to avoid destructive ground or air resonance without the use of auxiliary lag dampers. A Duffing spring stiffness is defined as a function of the cube of the spring displacement: F = Kd x3, as compared to the linear spring relation F = K x. This nonlinearity in the Duffing Equation leads to a shift in the resonant frequency as a function of the displacement. A three bladed articulated rotor model is employed similar to that used by Coleman in his classic work on ground resonance.
Nonlinear in-plane flexbeam stiffness provides rotor system stability without lag dampers
1999
10 Seiten, 17 Quellen
Aufsatz (Konferenz)
Englisch
Nonlinear Inplane Flexbeam Stiffness Provides Rotor System Stability Without Lag Dampers
Online Contents | 2001
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