Numerical study of a rotor-bearing-seal system

Seal and bearing characteristic is an important factor affecting the performance of the rotor system. The non-linear dynamic behaviours of a rotor-bearing-seal coupled system are investigated. Dynamic trajectories, Poincaré maps, largest Lyapunov exponents, frequency spectra, and bifurcation diagrams which are applied to analyse the features of the rotor-bearing-seal system in various parameters. Various non-linear phenomena in the rotor-bearing-seal system, such as periodic motion, double-periodic motion, multi-periodic, and quasi-periodic motion are investigated. The results of this study may contribute to a further understanding of the non-linear dynamics of such a rotor-bearing-seal coupled system.

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Non-linear dynamic behaviour of rotor—bearing system trained by bevel gears

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/09544062jmes843 ◽

2008 ◽

Vol 222 (4) ◽

pp. 617-627 ◽

Cited By ~ 3

Author(s):

M Li

Keyword(s):

Equilibrium Points ◽

Rotor System ◽

Design Stage ◽

Oil Film ◽

Bevel Gears ◽

Linear Dynamic ◽

Non Linear ◽

Rotor Bearing ◽

Stability And Bifurcations ◽

Bearing System

The vibrations of parallel geared rotor—bearing system have been intensively discussed; however, little attention has been paid to the dynamic analysis of angled bevel-geared system supported on journals. In the present work, the non-linear dynamics of a bevel-geared rotor system on oil film bearings is studied. First, the dynamic model is developed under some assumptions, such as rigid rotors, short-bearings, small teeth errors, and so forth. Then, the non-linear dynamic behaviours of both the balanced and unbalanced rotor system are analysed, respectively, in which the equilibrium points, limit cycles, their stability, and bifurcations are paid more attention. Numerical results show that in the bevel-geared rotor system under the action of non-linear oil film forces there exists a series of complex non-linear dynamic phenomena of rotor orbits, such as Hopf bifurcation, torus-doubling bifurcation, and jump phenomenon. All these features can help us to understand the dynamic characteristics of bevel-geared rotor—bearing system at design stage and during running period. Finally, some concerned problems during the investigation are also present.

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Eccentricity and Rotational Speed Effect on the Rotor-Bearing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.274.237 ◽

2013 ◽

Vol 274 ◽

pp. 237-240

Author(s):

Bing Dai ◽

Guang Bin Yu ◽

Jun Peng Shao ◽

Long Huang

Keyword(s):

Periodic Motion ◽

High Speed ◽

Element Model ◽

Turbine Rotor ◽

Radial Deformation ◽

Force Model ◽

Actual System ◽

Non Linear ◽

Rotor Bearing ◽

Bearing System

Bearing dimensionless nonlinear oil film force model is deduced based on Capone theory of cylindrical bearings in this paper. Jeffcot rigid rotor-bearing system dynamic equations are built based on nonlinear dynamics, bifurcation, chaos theory. Eccentricity increases with the speed of the system by writing MATLAB codes. It appears the periodic motion, times of periodic motion and a series of non-linear kinetics. The system eccentricity increases with a series of emergence of non-linear dynamics when speed conditions is fixed, which is the actual system design’s basis. The finite element model of gas turbine rotor-bearing system is built by ANSYS software platform in this paper. The radial bearing deformation relationship are obtained by deformation theory of centrifugal force at high speed bearing radial deformation.

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Effect of Friction on Dynamics of Gear System Featuring Confluence Transmission

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.163.18 ◽

2012 ◽

Vol 163 ◽

pp. 18-22 ◽

Cited By ~ 2

Author(s):

Hao Dong Gao ◽

Yi Du Zhang ◽

Xiang Sheng Gao

Keyword(s):

Dynamic Model ◽

Dynamic Behavior ◽

Dynamic Characteristics ◽

Periodic Motion ◽

Gear System ◽

Jump Phenomenon ◽

Linear Dynamic ◽

Non Linear ◽

Gear Systems ◽

The Impact

In order to investigate the effect of friction on gear system featuring confluence transmission, a non-linear dynamic model of three-gear system having two gear pairs was built. The influence of gear systems dynamic characteristics caused by changing of friction coefcient was researched. With the changing of friction coefcient, left-right gear pairs show dynamic behavior with coexist of same periodic motion, coexist of different periodic motion and chaos. With the increase of friction coefcient, the jump phenomenon of amplitude occurred, the impact of gear system became larger.

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On the non-linear dynamic behavior of a rotor–bearing system

Journal of Sound and Vibration ◽

10.1016/s0022-460x(03)00663-1 ◽

2004 ◽

Vol 274 (3-5) ◽

pp. 1031-1044 ◽

Cited By ~ 59

Author(s):

Jing JianPing ◽

Meng Guang ◽

Sun Yi ◽

Xia SongBo

Keyword(s):

Dynamic Behavior ◽

Linear Dynamic ◽

Non Linear ◽

Rotor Bearing ◽

Bearing System

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Numerical study of the velocity field predicted downstream a jet in cross flow using linear and non-linear turbulence models

10.26678/abcm.cobem2019.cob2019-1939 ◽

2019 ◽

Author(s):

Kelvin Cristófalo de Morais ◽

Luis Santos ◽

Claudia Andrade

Keyword(s):

Velocity Field ◽

Numerical Study ◽

Cross Flow ◽

Turbulence Models ◽

Jet In Cross Flow ◽

Non Linear

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Non-linear dynamic joint selection strategy for Hinge controlled masonry arches

10.1063/5.0026431 ◽

2020 ◽

Author(s):

Gabriel Stockdale ◽

Vasilis Sarhosis ◽

Gabriele Milani

Keyword(s):

Selection Strategy ◽

Masonry Arches ◽

Linear Dynamic ◽

Non Linear

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Un-Shocked High Amplitude Standing Waves in Wave-Shaped Resonators

Volume 12: Vibration, Acoustics and Wave Propagation ◽

10.1115/imece2012-88982 ◽

2012 ◽

Author(s):

Dion Savio Antao ◽

Bakhtier Farouk

Keyword(s):

Numerical Study ◽

Fluid Dynamic ◽

Ambient Pressure ◽

Standing Waves ◽

High Amplitude ◽

Prime Mover ◽

Non Linear ◽

Resonator System ◽

Cylindrical Resonators ◽

Linear Nature

A numerical study of non-linear, high amplitude standing waves in non-cylindrical circular resonators is reported here. These waves are shock-less and can generate peak acoustic overpressures that can exceed the ambient pressure by three/four times its nominal value. A high fidelity compressible computational fluid dynamic model is used to simulate the phenomena in cylindrical and arbitrarily shaped axisymmetric resonators. A right circular cylinder and frustum of cone are the two geometries studied. The model is validated using past numerical and experimental results of standing waves in cylindrical resonators. The non-linear nature of the harmonic response of the frustum of cone resonator system is investigated for two different working fluids (carbon dioxide and argon) operating at various values of piston amplitude. The high amplitude non-linear oscillations demonstrated can be used as a prime mover in a variety of applications including thermoacoustic cryocooling.

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