Active magnetic dampers for controlling lateral rotor vibration in high-speed rotating shafts

The whirling of a spinning top

Aeronautical Quarterly ◽

10.1017/s0001925900000299 ◽

1950 ◽

Vol 2 (1) ◽

pp. 9-14

Author(s):

J. Morris

Keyword(s):

High Speed ◽

Moments Of Inertia ◽

Prime Movers ◽

Rotating Shafts ◽

The Common ◽

The Stability ◽

Spinning Top

SummaryThis paper has been compiled because of the applicability of the treatment of the stability of the motion of the common spinning top to the problem of the whirling of rotating shafts, carrying loads of appreciable moments of inertia. This problem is assuming renewed interest and importance, especially in the drives of contra-propeller systems and the more recent high speed prime movers.

Download Full-text

High Speed Rotating Shafts Design Algorithm

14th Biennial Conference on Mechanical Vibration and Noise: Vibration of Rotating Systems ◽

10.1115/detc1993-0197 ◽

1993 ◽

Author(s):

Po Kee Wong

Keyword(s):

Spectrum Analysis ◽

High Speed ◽

Wave Spectrum ◽

Vibrational Modes ◽

Elastic Rod ◽

Design Algorithm ◽

The Public ◽

Rotating Shafts ◽

First Time

Abstract This paper reveals an invention for the first time to the public about the fundamental concepts for the design of high speed rotating shafts based on the wave spectrum analysis of the vibrational modes of elastic circular rods and shells that was completed in 1967, even though the Pochhammer-Chree-Love solution of the transversal (n = 1) vibration of a solid elastic rod was originated by Pochhammer in 1876.

Download Full-text

A Contribution on the Investigation of the Dynamic Behaviour of Rotating Shafts With a Hybrid Magnetic Bearing Concept (HMBC) for Blower Application

Fourth International Topical Meeting on High Temperature Reactor Technology, Volume 1 ◽

10.1115/htr2008-58045 ◽

2008 ◽

Cited By ~ 1

Author(s):

Martin Gronek ◽

Torsten Rottenbach ◽

Frank Worlitz

Keyword(s):

Energy Supply ◽

High Speed ◽

Experimental Tests ◽

Magnetic Bearing ◽

Active Magnetic Bearing ◽

Analytical Models ◽

Test Facility ◽

Reactor Technology ◽

Rotating Shafts ◽

Technical Features

Within a subproject of the RAPHAEL-Program, which is part of the 6th EURATOM Framework Program supervised by the European Commission it was investigated whether the use of a Hybrid Magnetic Bearing Concept (HMBC) will be beneficial for a blower application. As in the RAPHAEL program the subproject “Component Development” deals with R&D on components of High Temperature Reactor Technology (HTR), a major focus is on safety- and reliability-related issues. That implies special requirements for the support of high speed rotating shafts in HTR-Applications that only can be satisfied by using Active Magnetic Bearings (AMB). Regarding safety and competitiveness, AMBs are considered key components for the support of rotating HTR-components due to their technical features. AMBs are characterized by an electromagnetic actuator that is generating the bearing force depending on the clearance between stator and rotor, in which the rotor is levitated. Therefore an active control of the coil current is necessary. Furthermore, Touch Down Bearings (TDB) are needed to avoid damages in case of an emergency shut down or in case of energy supply losses. This contribution provides an internal insight on the advantages of a Hybrid Magnetic Bearing Concept that is characterized by a completely Active Magnetic Bearing-supported vertical arranged rotor and an additional permanent magnetic Radial Bearing. One benefit of the HMBC is an additional radial guidance of the shaft that may reduce the loads while dropping into the Touch Down Bearings e.g. in case of energy supply losses of the AMBs. Reduced loads on the TDBs will increase their life cycle and the availability of the AMB supported component. The Scope of this R&D-Project, which will be described more detailed in this contribution, includes the analytical modeling and simulation of the dynamic behavior of the Hybrid Magnetic Bearing System, the modification of the completely AMB-supported test facility FLP500 with a radial PMB and the experimental tests and validation of the analytical models to provide recommendations for the investigated blower application as an HTR-component. Furthermore, the effects occurring during the modification of the test facility and the approach that was necessary to solve unexpected problems will be described.

Download Full-text

Forced Wave Motion of Liquid Partially Filling a High-Speed Rotor

Journal of Vibration and Acoustics ◽

10.1115/1.3269286 ◽

1985 ◽

Vol 107 (4) ◽

pp. 446-452

Author(s):

J. Inoue ◽

Y. Jinnouchi ◽

Y. Araki

Keyword(s):

High Speed ◽

Wave Motion ◽

Equations Of Motion ◽

Governing Equations ◽

Rotor Vibration ◽

Liquid Motion ◽

Large Wave ◽

Main Emphasis ◽

Two Dimensional Flow ◽

Theoretical Results

Wave motion of a liquid in a partially filled hollow cylindrical rotor, which rotates at a high speed and is forced to vibrate, is theoretically and experimentally investigated. Main emphasis is placed on the analysis of a large wave motion in the liquid which may cause self-excited vibrations of the rotor. Assuming a thin liquid layer, simplified equations of motion are derived by integration of the governing equations for a two-dimensional flow. Nonlinearity and viscosity are taken into account in the analysis. A large wave motion with a broken wavecrest is analyzed by applying a theory of hydraulic jump. Illustrating typical examples of the theoretical results together with the experimental ones, the dynamic behavior of the liquid motion and the basic relations between the liquid force and the rotor vibration are discussed.

Download Full-text

Some Features of Rotor Dynamics inside Floating Sealing Ring

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.113.247 ◽

2006 ◽

Vol 113 ◽

pp. 247-251

Author(s):

L.Y. Banakh ◽

A.N. Nikiforov ◽

G.Y. Panovko

Keyword(s):

High Speed ◽

Rotor Dynamics ◽

Rotor Vibration ◽

Coupled Vibrations ◽

Dynamic Forces ◽

Sealing Ring ◽

Turbo Pump

Flow-coupled vibrations of system “rotor-ring” are researched. Absence effect of critical rotor velocity and dynamic absorption of rotor vibration in the system “rotor-ring” is described. These properties are caused by aero(hydro)dynamic forces in the clearance between rotor and ring. Result of lowered vibration for high-speed rotor of turbo-pump containing floating sealing rings is submitted.

Download Full-text

Dynamic Stability of the Rotating Shaft Made of Boltzmann Viscoelastic Solid

Journal of Applied Mechanics ◽

10.1115/1.3171775 ◽

1986 ◽

Vol 53 (2) ◽

pp. 424-429 ◽

Cited By ~ 8

Author(s):

W. Zhang ◽

F. H. Ling

Keyword(s):

Dynamic Stability ◽

High Speed ◽

Static Load ◽

Viscoelastic Solid ◽

Rotating Shaft ◽

Special Cases ◽

Analytical Formulas ◽

Rotating Shafts ◽

The Stability ◽

Inclined Angle

A general theory is developed in this paper for studying the dynamic stability of high-speed nonuniform rotating shafts made of a Boltzmann viscoelastic solid. The equation of motion of the shaft is deduced. The stability criteria are derived by using this equation. The unstable regions for a nonhomogeneous viscoelastic shaft are worked out numerically. Analytical formulas are also given in this paper for determining the planar deflection of the shaft and its inclined angle due to a planar static load. The conclusions for special cases given in the literature known to the authors are all covered by the results in this paper.

Download Full-text

The Effect of Bistable Jump on the Reliability of Squeeze Film Damper

13th Biennial Conference on Mechanical Vibration and Noise: Rotating Machinery and Vehicle Dynamics ◽

10.1115/detc1991-0252 ◽

1991 ◽

Author(s):

Zhu Changsheng

Keyword(s):

High Speed ◽

Operating Time ◽

Squeeze Film ◽

Jump Phenomenon ◽

Rotor Vibration ◽

Squeeze Film Damper ◽

Operation Speed ◽

Squeeze Film Dampers ◽

Speed Range ◽

Pass Through

Abstract Based on lots of data from an experiment of a high-speed rotor supported on squeeze film dampers, this paper analyses that how the bistable jump affects the reliability of squeeze film dampers, if the rotor system has to frequently pass through the bistable oparation speed range. It is shown that the change of the rotor vibration amplitudes caused by times of passed through bistable operation speed range is more significant than that caused by steady operating time. The users must pay much attention to the bistable jump phenomenon in the successful application of squeeze film dampers.

Download Full-text

Research on Identification Method of Multi-Mixed Vibration Signal of Aeroengine

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.419-420.801 ◽

2009 ◽

Vol 419-420 ◽

pp. 801-804

Author(s):

Xiang Yang Jin ◽

Shi Sheng Zhong

Keyword(s):

Fault Diagnosis ◽

Blind Source Separation ◽

Source Separation ◽

Vibration Signal ◽

Signal Separation ◽

Rotor Vibration ◽

Vibration Signals ◽

Vibration Data ◽

Monitoring And Diagnosis ◽

Rotating Shafts

The effectiveness of separation and identification of mechanical signals vibrations is crucial to successful fault diagnosis in the condition monitoring and diagnosis of complex machines.Aeroengine vibration signals always include many complicated components, blind source separation (BSS) provides a efficient way to separate the independent component.In order to get the most effective algorithm of vibration signal separation,experiment has been done to acquire plenty of multi-mixed rotor vibration signals,three sets of vibration data generated from aeroengine rotating shafts were separated from the synthetic vibration signal. The results prove that blind source separation is effective and can be applied for vibration signal processing and fault diagnosis of aeroengine.

Download Full-text