Research on Transverse Vibration Characteristic of Rotating Cracked Beams with Variable Cross-section

Abstract

The dynamic characteristics analysis of damage structure is an important basis for non-destructive testing. However, there are few literatures concerning the study of dynamic characteristics of rotating cracked beams. Taking rotating cracked beams with variable cross-section as the research object, the transverse vibration characteristics of rotating cracked beams are investigated, and a new method to solve the transverse vibration characteristics of rotating cracked beams is proposed. The torsion spring is used to simulate the crack effect, and the flexibility model of cracked beams model is established. The Frobenius method is used to solve the vibration equation, and obtain the series analytic solution of the equation. The effect of crack position and depth on vibration frequency is studied, and the variation of first two-order natural frequency of beam is analyzed under different damage degrees and speeds. The results show that the proposed method is effective, the change of rotating speed and damage degree do not affect the natural frequency of the beam independently, and there is a coupling mechanism between the two items. The conclusions are suitable for beams with variable cross-section.

Keywords

• rotating cracked beam
• transverse vibration
• natural frequency
• coupling mechanism