in this paper, exact solution for two-plane transverse vibration analysis of axial-loaded multi-step timoshenko rotor carrying concentrated masses is presented. each attached element is considered to have both translational and rotational inertia. forward and backward frequencies and corresponding modes are obtained using transfer matrix method (tmm). the effect of the angular velocity of spin,...

In this paper, two kinds of vibrations are considered for a composite Timoshenko rotor: longitudinal-torsional vibration and two plane transverse one. The kinetic and potential energies and virtual work due to the gyroscopic effects are calculated and the set of six governing equations and boundary conditions are derived using Hamilton principle. Differential quadrature method (DQM) is used as ...

Catcher bearings (CB) are an essential component for rotating machine with active magnetic bearings (AMBs) suspensions. The CB’s role is to protect the magnetic bearing and other close clearance component in the event of an AMB failure. The contact load, the Hertzian stress, and the sub/surface shear stress between rotor, races, and balls are calculated, using a nonlinear ball bearing model wit...

In this paper, exact solution for two-plane transverse vibration analysis of axial-loaded multi-step Timoshenko rotor carrying concentrated masses is presented. Each attached element is considered to have both translational and rotational inertia. Forward and backward frequencies and corresponding modes are obtained using transfer matrix method (TMM). The effect of the angular velocity of spin,...

Aiming at the non-stationary and stall flutter problems of wind turbine blade caused by transient load fluctuations, the dynamic properties of wind turbine were studied, the blade was simplify to a cantilever beam in case of the action of shear deformation and cross section rotating effect were considered in this analysis, equations of the blade were established based on D'Alemberts' principle ...

The rotor misalignment fault, which occurs only second to imbalance, easily in the practical rotating machinery system. Rotor can be further divided into coupling and bearing misalignment. However, most of existing references analyze effect on dynamic characteristics system ignore change excitation caused by Based above limitations, a five degrees freedom nonlinear restoring force mathematical ...

This work presents a technique that allows the calibration of mathematical models in rotating systems. The method is based on the application of a hybrid meta-heuristic search, which employs genetic algorithm and simulated annealing. The capabilities of the method are evaluated by means of experimental results obtained in the test-rig of Politecnico di Milano. The experimental set up consists o...

The turbine shared support structure is used widely in aeroengines, but theoretical and experimental research on a rotor-bearing system containing lacking. This paper reports into the coupling vibration response of squeeze-film-damper that has two spools with different rotation speeds supported by structure. problem addressed means tests finite-element method. Based features turboshaft engine s...

In this paper, a mathematical model of rotor-bearing system is presented. The includes modal elastodynamics flexible rotor as well the in-plane radial dynamics bearing with outer race. Elastodynamics shaft utilises solution based on Green's function to provide computationally efficient approach. race modelled using Timoshenko beam theory. also detailed lubricated contact mechanics balls-to-race...

In the present study, an accurate model is used for analyzing asymmetric shaft with misalignment and under unbalance forces in rotating coordinates verified by developing experimental test.The rotor modeled Timoshenko beam theory coupled to a motor.The differential equations of motion are discretized Rayleigh-Ritz method derived from Hamilton's principle. Thereafter, According results, frequenc...