Journal of KSNVE (소음진동)

The Korean Society for Noise and Vibration Engineering (한국소음진동공학회)
권호 표지

Identification of Crack Orientation in a Simple Rotor

회전체에서의 균열 방위 결정

  • Jun, Oh Sung (Dept. of mechanical engineering, Jeonju University, Jeonju, 560-759, Korea) ;
  • Lee, Chong-Won (Dept. of mechanical engineering, KAIST Tae-Jeon, 560-759, Korea) ;
  • Lim, Byoung Duk (School of mechanical Engineering Yeungnam University)
  • Published : 1997.04.01
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Abstract

Vibration characteristics which are typical in a cracked rotor can be utilized for detection of crack. The changing trend of harmonics at the second harmonic resonant speed according to the crack depth and the unbalance orientation has been discussed. To characterize the vibration depending on crack orientation, the unbalance and gravitational responses of the cracked rotor are calculated. An algorithm for crack orientation identification is also introduced. A trial mass is attached step by step with even angle interval along a certain circumference, and then the synchronous and second horizontal harmonic compenents of vibration are measured and curve-fitted using least square method. Numerical simulations using this method show good results.

균열을 가진 회전축은 고조파성분이 진동에 나타나는 특징을 갖는다. 이 고조파성분을 균열탐지에 활용하기 위하여는 이들이 크게 발생되는 회전수를 이용할 필요가 있다. 2차고조파공진속도를 정의하여 이 속도에서의 균열과 불균형질량 방위각에 따른 고조파 진동 특성을 단순회전체에서 설명하였다. 이 특성을 이용하여 균열의 위치를 나타낼 수 있는 알고리즘을 만들고 수치실험을 하여 타당성을 보였다.

Keywords

References

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