在任意位置激振时周期简支梁的功率流

Vibrational Power Flow In A Periodically Supported Beam Excited at Any Position

本文进一步研究周期简支梁在力激振时的振动功率流,分析激振位置对振源向梁输入功率流和沿梁传播功率流的特点。在不同传播域中可适当调整振源位置从而减少输入功率流,但是不管在何点激振,沿梁正向和沿梁反向传播的功率流相等,且等于输入功率流的一半。文中还讨论结构阻尼对减少输入功率流和传播功率流的作用,阻尼在奇数传播域界频率处有效地控制输入功率流,而在传播域中有效地损耗传播功率流。

The vibrational power flow in a spatially periodic supported beam is furtherstudied. The influence of excitation location on transmitted and travelling powerflow is investigated. For different propagation bands, the transmitted powerflow can be reduced to the minimum by suitably adjusting the excitation position.No matter where the beam is excited, Power flow travelling along the beam inthe positive and negative direction are same and equal one half of thetransmitted power flow. The effect of structural damping on power flow is alsostudied. In this case the periodic beam is excited at the middle point of one bay.The transmitted power flow is effectively controlled by the damping near thebounding frequencies of the odd propagation bands. The travelling power flowis effectively decreased by damping in the propagation bands.