0
Research Papers

Elimination of Unstable Ranges of Rotors Utilizing Discontinuous Spring Characteristics: An Asymmetrical Shaft System, an Asymmetrical Rotor System, and a Rotor System With Liquid

[+] Author and Article Information
Yukio Ishida

Department of Mechanical Science and Engineering, School of Engineering, Nagoya University, Nagoya, Aichi 464-8603, Japanishida@nuem.nagoya-u.ac.jp

Jun Liu

Department of Mechanical Science and Engineering, School of Engineering, Nagoya University, Nagoya, Aichi 464-8603, Japanliu@nuem.nagoya-u.ac.jp

J. Vib. Acoust 132(1), 011011 (Feb 01, 2010) (8 pages) doi:10.1115/1.4000842 History: Received April 16, 2007; Revised April 09, 2008; Published February 01, 2010; Online February 01, 2010

Unstable vibration occurs in the vicinities of the major critical speeds of asymmetrical shaft and rotor systems. It occurs also in a wide rotational speed range higher than the major critical speed of a shaft with a hollow disk partially filled with liquid. The occurrence of the unstable vibrations is a serious problem because the amplitude increases exponentially, and finally, the system is destroyed. The active vibration control can suppress unstable vibrations but the method is generally complicated and costly. No simple effective method to suppress unstable vibrations has been developed yet. In the previous paper, the authors proposed a simple method by utilizing discontinuous spring characteristics, which can suppress steady-state resonances. This paper shows that this method is also effective to suppress unstable vibrations. By using this method, the unstable vibrations can be changed into almost periodic motions, and the amplitudes are suppressed to the desired small level even in an unstable range. The validity of the proposed method is also verified by experiments.

Copyright © 2010 by American Society of Mechanical Engineers
Topics: Rotors , Springs
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

2DOF rotor system models (asymmtrical shaft system and rotor system with liquid)

Grahic Jump Location
Figure 2

Spring characteristic with additional spring in the x-direction

Grahic Jump Location
Figure 3

4DOF rotor system model (asymmetrical rotor system)

Grahic Jump Location
Figure 4

Natural frequency diagram of a 2DOF asymmetrical shaft system

Grahic Jump Location
Figure 13

Experimental result of an asymmetrical shaft system (case with additional springs, with a directional difference in stiffness)

Grahic Jump Location
Figure 14

Experimental result of a rotor system with liquid (case without additional springs) and numerical result

Grahic Jump Location
Figure 15

Experimental result of a rotor system with liquid (case with additional springs, with a directional difference in stiffness)

Grahic Jump Location
Figure 5

Natural frequency diagram of a 4DOF asymmetrical rotor system

Grahic Jump Location
Figure 6

Natural frequency diagram of a 2DOF rotor system with liquid

Grahic Jump Location
Figure 7

Resonance curves (asymmetrical shaft system, c2 small)

Grahic Jump Location
Figure 8

Resonance curves (asymmetrical shaft system, c2 large)

Grahic Jump Location
Figure 9

Resonance curves (asymmetrical rotor system)

Grahic Jump Location
Figure 10

Resonance curves (rotor system with liquid)

Grahic Jump Location
Figure 11

Experimental setup

Grahic Jump Location
Figure 12

Experimental result of an asymmetrical shaft system (case without additional springs) and numerical result

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In