In this paper, the dynamic balance of a rigid variable speed rotor is tested and analyzed. The vibration acceleration measured by analyzer instrumentations. adjustment parameters counterweight, pitch, trailing-edge flap are considered. amplitude phase 1 Ω analyzed through an all-phase fast Fourier transform. experiments conducted using two rotors with same geometry. accelerations fuselage in x,...

A morphing segmented concept is proposed herein for future extreme-scale wind turbine systems. The morphing may be accomplished by using segmented blades connected by screw sockets and a tension cable system. At low wind and rotor speeds, the segmented blades are fully tensioned and set at high pitch to ensure start-up and maximum power at low speeds. At high rotor rpm, the cable tension can be...

ABSTRACT Blade failure is a common problem of a steam turbine and it’s failure in-service results in safety risks, repair cost and non operational revenue losses. Thus, the reliability of these blades is very important for the successful operation of a steam turbine. Dynamic analysis of a steam turbine blade in computational environment is carried out in the present work. In order to gain physi...

The contactless nature of active magnetic bearings brings about many advantages over the conventional bearing while industrial real-time applications are often limited by the significant complexity of control algorithms. This paper presents the application of an LQ controller to an active magnetic bearing system (AMB). Two control strategies are presented and compared: local and global. In the ...

This paper deals with the development of a model based method for bearing fault diagnostics. This method effectively combines the information available in the data and the model for efficient classification of the bearing and the type of defect. A four degrees of freedom nonlinear rigid rotor model is used to simulate the rotor bearing system. Precession of the shaft is measured using proximity...

This paper presents an analytical study of single-plane automatic balancing of statically and dynamically unbalanced rigid rotors, considering also the effect of partial unbalance compensation and vibration reduction. We consider a rotor equipped with a selfbalancing device consisting of a circular track with moving balls to compensate for rotor unbalance. The investigations include an analysis...

Abstmcf: Flight testing of a fully-instrumented model-scale unmanned helicopter (Yamaha R-SO with loft. diameter rotor) was conducted for the purpose of dynamic model identification. This paper describes the application of CIFER' system identification techniques, which have been developed for full size helicopters, to this aircraft. An accurate, high-bandwidth, linear state-space model was deri...

Volterra and Wiener theories provide the concepts of linear, bilinear, tri-linear, etc., kernels, which upon convolution with the excitation force, can be employed to represent the response of a nonlinear system. Based on these theories, higher-order frequency response functions (FRFs) are employed to estimate the nonlinear stiffness of rolling element bearings, supporting a rigid rotor. The ro...

this work deals with effects of asymmetric stiffness on the dynamic behaviour of the rotor system. the analysis is presented through an extended lagrangian hamiltonian mechanics on the asymmetric rotor system, where symmetries are broken in terms of the rotor stiffness. the complete dynamics of asymmetries of rotor system is investigated with a case study. in this work, a mathematical model is ...

Rotors with high gyroscopic effects and low resonance frequencies caused by the blade wheel (blade frequencies) can lead to stabilization problems in the application field of turbomolecular pumps. If such a rotor is stabilized by active magnetic bearings, the control structure could be destabilized by the splitting up of the rigid body eigen-frequencies caused by the gyroscopic effect. The cont...