... to relate both on-axis and off-axis responses by the gyroscopic moments through the actuation mechanism of hingeless helicopters. This new method allows investigators to directly and analytically quantify the debatable cross-coupling due to the complex actuation of the rotor. This method is based...

...P. K. Kankar; Satish C. Sharma; S. P. Harsha In this paper the nonlinear dynamic responses of a rigid rotor supported by ball bearings due to surface waviness of bearing races are analyzed. A mathematical formulation has been derived with consideration of the nonlinear springs and nonlinear damping...

... ∂ T ∂ x p ψ + 2 ψ t T ∂ ψ ∂ x p where T can denote the global mass or stiffness matrix. An experimental modal analysis was conducted on a MGV rotor hanged from a crane via a swivel hoist ring to achieve free-free boundary conditions at best (Fig. 4...

... low viscosity under high oil inlet temperature and low feed pressure. The development of high performing bearing systems, marrying innovation with reliability, is a persistent challenge. This paper shows progress on the nonlinear dynamic behavior modeling of the rotor-radial bearing system (RBS...

...Matthew S. Allen A variety of systems can be faithfully modeled as linear with coefficients that vary periodically with time or linear time-periodic (LTP). Examples include anisotropic rotor-bearing systems, wind turbines, and nonlinear systems linearized about a periodic trajectory. Many...

... response. Lalanne , M. , and Ferraris , G. , 1998 , Rotordynamics Predictions in Engineering , 2nd ed. , Wiley , New York . Rao , J. S. , 1991 , Rotor Dynamics , 2nd ed. , Wiley , New York . Krämer , E. , 1993 , Dynamics of Rotors and Foundations , Springer...

...J. L. Palacios Felix; J. M. Balthazar; R. M. L. R. F. Brasil The paper presents a number of numerical simulations of the transverse vibrations of two (or one) unbalanced rotors forced by an electric motor, with limited power supply, during the passage through of the two resonance zones (increasing...

... on the stability of the integration scheme. Simple C ° shape functions are used in the spatial discretization of the state variables owing to the weak form of the model. Numerical solution of the transient behavior of multibody systems, representative of various rotor blade system configurations, is presented...

...Jiazhong Zhang; Wei Kang; Yan Liu From the viewpoint of nonlinear dynamics, the stability and bifurcation of the rotor dynamical system supported in gas bearings are investigated. First, the dynamical model of gas bearing-Jeffcott rotor system is given, and the finite element method is used...

..., which can be used as a design parameter to influence absorber performance, both in terms of rotor vibration reduction and operating range. This paper reviews the basic analysis, which employs scaling and averaging, and extends it to include the detuning. In addition, systematic experiments of systems...

...N. Driot; C. H. Lamarque; A. Berlioz In this study, the dynamic behavior of a flexible rotor system subjected to support excitation (imposed displacements of its base) is analyzed. The effect of an excitation on lateral displacements is investigated from theoretical and experimental points of view...