Rotating machinery is often subjected to variable loads during operation. Thus, monitoring and identifying different load types is important. Here, five typical load types have been qualitatively studied for a rotor system. A novel load category identification method for rotor system based on vibration signals is proposed. This method is a combination of ensemble empirical mode decomposition (E...

In order to have fault identification for the gate rotor shaft with multiple cracks effectively, the quantity identification method of the gate rotor shaft with multiple cracks based on wavelet finite element method is established and the frequency test of the gate rotor shaft based on blind source separation algorithm is analyzed. Firstly the wavelet finite element was established by combining...

Electromagnetic fields in the air gap of an electric machine produce electromagnetic forces between the rotor and stator. The total force exerted on the rotor due to the eccentric rotor position is called the unbalanced magnetic pull. This eccentricity force is directed roughly over the shortest air gap. At low frequencies, the vibration amplitudes of flexural modes may be large enough to coupl...

Title of dissertation: COMPREHENSIVE AEROELASTIC ANALYSIS OF HELICOPTER ROTOR WITH TRAILING-EDGE FLAP FOR PRIMARY CONTROL AND VIBRATION CONTROL Jinwei Shen, Doctor of Philosophy, 2003 Dissertation directed by: Professor Inderjit Chopra Department of Aerospace Engineering A comprehensive aeroelastic analytical model of helicopter rotors with trailingedge flaps for primary and vibration controls ...

Rigid rotor dynamic model is widely used to model rotating machinery. In this paper, a speed-varying transient rigid rotor model is developed in the state space form. The states of this model are augmented to include imbalance forces and moments. A time-varying observer can then be designed for the augmented system by using canonical transformation. After obtaining an estimation of the imbalanc...

Unbalance response is a common vibration problem associated with rotating machinery. For several years, researchers have demonstrated that this vibration could be greatly alleviated for machines using active magnetic bearings through active control. Many of the control strategies employed fall into a class which the authors have termed adaptive open loop control. In this paper, three algorithms...

Turbochargers are widely used on commercial automotive vehicles, power generation and marine applications. A comprehensive model for a turbocharger would be an effective tool for fault detection. In this paper, research focus on mathematical modelling of turbochargers supported on floating ring bearings in rotordynamics. Nonlinear hydrodynamic forces are considered in order to describe the dyna...

The nonlinear dynamic model of rotor-bearing-seal system with crack in shaft is set up based on the coupling model of nonlinear oil-film force and Muszyska’s nonlinear seal fluid force. The dynamic vibration characteristics of the rotor-bearing-seal system and the effects of physical and structural parameters of labyrinth seal and crack fault on movement character of the rotor were analyzed. Th...

This paper proposes an approach to improve stability and active control of rotor vibration by the use of Model Predictive controller. Rotor vibrations in electrical machines are dampen out by model predictive control algorithm. The controlled system is the one dimensional Jeffcott-rotor. Model predictive control algorithm was designed, and the simulation results were obtained by Mat lab softwar...

The rolling bearings dynamical behaviour analysis is a important condition to determine the machine vibration response. The rolling bearing, with outer ring fixed, is a multi body mechanical system with rolling elements that transmit motion and load from the inner raceway to the outer raceway.Modern trend of Dynamic analysis is useful in early prediction; simulation of rotor bearing system as m...