Random mistuning을 고려한 회전하는 멀티 패킷 블레이드 시스템의 진동 국부화

Abstract

Vibration localization of mistuned multi-packet blade system undergoing multiple nozzle excitation forces was investigated. The equations of motion of rotating multi-packet blade system undergoing multiple nozzle excitation forces are derived using Kane’s method. Since the blades are grouped in the packets by shroud, the vibration energy is often confined to the packet or packets in mistuned multi-packet blade systems. In order to investigate the effect of mode localization on dynamic responses of mistuned multi-packet blade system, not only modal but also transient analyses are carried out using the equations of motion. The results of modal and transient analyses herein reveal that there are dominant and trivial modes for dynamic responses depending on the number of nozzles and operating speed. To design the mistuned multi-packet blade system, length of blades are randomly mistuned.