Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Modal Analysis of Rotor System with Anisotropic Stator and Asymmetric Rotor in the Presence of Breathing Crack

개폐균열이 존재하는 비대칭 회전부 및 비등방 고정부를 갖는 회전체의 모드해석

  • 한동주 ((주)썬에어로시스 기술연구소)
  • Published : 2006.04.01
Download PDF
⟨ Previous Next ⟩

Abstract

This paper describes the new modal analysis method to detect the presence of the breathing crack in a general rotor system with disk asymmetry and stator anisotropy. It is proposed that the modal analysis using directional frequency response functions (dFRFs), which, accounting for the directivity in modes, clears the heavily over-lapping of other harmonics occurring from non-isotropic properties in addition to those due to crack, can provide an effective method to detect the modes by a crack. The simulations from the simple general rotor model show that the r-dFRFs (reverse dFRFs) for asymmetry confirms a good indicator of the presence of the breathing crack and the instability is primarily influenced by the shaft asymmetry than the breathing crack.

Keywords

References

  1. Iman, I., Azzaro, S. H. and Bankert, R. J., 1989, 'Development of an On-Line Rotor Crack Detecting and Monitoring System,' Journal of Vibration, Acoustics, Stress, and Reliability in Design, Vol. 111, pp. 241-250 https://doi.org/10.1115/1.3269848
  2. Miller, et al, 1990, 'Shaft Crack Detection Method,' U.S. Patent, No. 4975855
  3. Soffker, D., Bajkowski, J. and Muller, P. C., 1993, 'Detection of Cracks in Turborotors - A New Observer Based Method,' Journal of Dynamic Systems, Measurement, and Control, Vol. 115, pp. 518-524 https://doi.org/10.1115/1.2899130
  4. Lee, C. W., Yun, J. S. and Jun, O. S., 'Modeling of a Simple Rotor with a Switching Crack and Its Experimental Verification, 1992,' Journal of Vibration and Acoustics, Vol. 114, pp. 217-225 https://doi.org/10.1115/1.2930251
  5. Garsh, R. and Person, M., 'Dynamic Behavior of the Laval Rotor with a Cracked Hollow Shaft-a Comparison of Crack Models, 1988,' Proceedings of the Institution of Mechanical Engineers, Vibrations in Rotating Machinery, pp. 463-472
  6. Mayes, I. W. and Davis, W. G. R., 'Analysis of the Response of a Multi-Rotor-Bearing System Containing a Transverse Crack in a Rotor, 1984,' Journal of Vibration, Acoustics, Stress, and Reliability in Design, Vol. 106, pp. 139-145
  7. Papadopoulos, C. A. and Dimarogonas, A. D., 1988, 'Stability of Cracked Rotors in the Coupled Vibration Mode,' Journal of Vibration, Acoustics, Stress, and Reliability in Design, Vol. 110, pp. 356-359 https://doi.org/10.1115/1.3269525
  8. Tamura. A. and Iwata, Y., 'Unstable Vibration of a Rotor with a Transverse Crack, 1988,' Proceedings of the Institution of Mechanical Engineers, Vibrations in Rotating Machinery, pp. 647-653
  9. Neson, H. D. and Nataraj, C., 1986, 'Stability of Cracked Rotors in the Coupled Vibration Mode,' Journal of Vibration, Acoustics, Stress, and Reliability in Design, Vol. 108, pp. 189-196 https://doi.org/10.1115/1.3269321
  10. Meng, G. and Garsh W., 2000, 'Stability and Stability Degree of a Cracked Flexible Rotor Supported on Journal Bearing,' Journal of Vibration and Acoustics, Vol. 122, pp. 116-125 https://doi.org/10.1115/1.568448
  11. Grabowski, B., 1980, 'The Vibration Behavior of a Turbine Rotor Containing a Transverse Crack,' ASME Journal of Mechanical Design, Vol. 102, pp. 140-146 https://doi.org/10.1115/1.3254704
  12. Kwon, K. S. and Lee, C. W., 2000, 'Random Excitation for Modal Testing of Rotating Machinery : Use of Modulation Technique,' Journal of Sound and Vibration, Vol. 234, pp.297-309 https://doi.org/10.1006/jsvi.1999.2868
  13. Suh, J. H., Hong, S. W. and Lee, C. W., 2005, 'Modal analysis of asymmetric rotor system with isotropic stator using modulated coordinates,' Journal of Sound and Vibration, Vol. 284, pp.651-671 https://doi.org/10.1016/j.jsv.2004.07.004
  14. Lee, C. W., Han, D. J., Suh, J. H. and Hong, S. W., 'Modal Analysis of Periodically Time-varying Linear Rotor Systems,' submitted to Journal of Sound and Vibration