Free Vibration and Dynamic Stability of the Axially Moving Continuum with Time-varying Length

축방향으로 이동하며 길이가 변하는 연속체의 자유 진동 및 동적 안정성

  • 사재천 (서강대학교 대학원 기계공학과) ;
  • 이민형 (세종대학교 기계공학) ;
  • 이승엽 (서강대학교 기계공학과)
  • Published : 2002.04.01


The time-dependent frequency and energy of free vibration of the spagetti problem, that is the axially moving continuum with time-varying length, are investigated. Exact expressions for the natural frequency and time-varying vibration energy are derived by dealing with traveling waves. The vibration period increases with increasing length, but the free vibration energy decreases. When the string undergoes retraction, the vibration energy increases with time. The free response of the time-varying string is represented by superposing two traveling waves.


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