A Study on the Measurement of Vibration Mode Shape using Holographic interferometry

홀로그래픽 간섭법을 이용한 진동모드의 계측에 관한 연구

  • Published : 2000.06.01

Abstract

In this study the vibration behavior of the stiffened double cylinder was experimently analyzed. Due to the complex structure of the double cylinder the outside cylinder frequency responses to the exciting forces applied on various posi-tions were analyzed by using spectrum analyzer in conjunction with an accelerometer and the natural frequencies were obtained. The technique of time-averaged holographic interferometry is applied to study the vibration characteristics of outside cylinder with stiffening T frame. The experimental data showed that the T frame had salient effect of damping on the testing structure at most of resonances. however the experimental results also revealed interesting phenomenon. At some particular frequencies the T frame. The experimental data showed that the T frame had salient effect of damping on the testing structure at most of resonances. However the experimental results also revealed interesting phenomenon. At some particular frequencies the T frame seemed to behave as a transmitter. In addition it has been successfully demon-started that optical method such as holographic interferometry is well suited for the identification of mode shapes. They can give us a whole-field non-contact measurement instead of the point-wise measurement by accelerometer in classical modal testing.

References

  1. Nature v.161 A New Microscopic Principle Gabor, D.
  2. J. Opt. Soc. Am. v.53 Wavefront Reconstruction with continuous-tone Objects Leith, E.;Upatnieks, J.
  3. J. Opt. Soc. Am. v.54 Wavefront Reconstruction with Diffused Illumination and Three-dimensional Objects Leith, E.;Upatnieks, J.
  4. J. Opt. Soc. Am. v.55 no.12 Interferometric Vibration Analysis by Wave-Front Reconstruction Powell, R.L.;Stetson, K.A.
  5. J. Opt. Soc. Am. v.22 no.19 An interferometer Method of Studying the Vibrations of An Oscillating Quartz Plate Osterberg, H.
  6. Experimental Mechanics Application of Holographic Interferometry to a Study of Wave Propagation in Rock Holloway, D.C.;Patacca, A.M.;Fourney, W.L.
  7. Optical Engineering v.21 no.3 Application of Holographic Interferometry to Stress Wave and Crack Propagation Problems Holloway, D.C.
  8. Experimental Mechanics v.29 no.4 Transient Bending Waves in Plates Studied by Hologram Interferometry Fallstrom, K.E.;Gustavsson, H.;Molin, N.E.;Wahlin, A.
  9. Experimental Mechanics v.29 no.4 Transient Bending Waves in Anisotropic Plates Studied by Hologram Interferometry Fallstrom, K.E.;Lindgren, L.E.;Molin, N.E.;Wahlin, A.
  10. 한국공작기계기술학회지 v.6 no.1 전자 스페클 간섭법에 의한 스피커 진동 해석 강영준
  11. Journal of Applied Mechanics v.37 no.2 Applications of Holography to Dynamics: High-Frequency Vibrations of Beams Aprahamian, R.;Evensen, D.A.
  12. Journal of Applied Mechanics v.37 no.4 Applications of Holography to Dynamics: High-Frequency Vibrations of Plates Aprahamian, R.;Evensen, D.A.
  13. Ph. D Dissertation, Dept. of Mech. Eng. Study of the Vibration of Bulkhead-Stiffened Cylindrical Shells by Laser-Based Methods Zhu, N.H.
  14. Vibrations of Shells and Plates Soedel, W.