基于能量等效原理的颤振机理及颤振导数识别

Study on flutter mechanism and identification of flutter derivatives based on energy equivalence

桥梁和风是相互作用的流固耦合系统,风对桥梁的作用效应可以分为阻尼效应和刚度效应。首先基于能量等效原理将Scanlan线性颤振自激力分为纯阻尼效应项H1^*、A2^*,纯刚度效应项A3^*、H4^*和既有刚度效应又有阻尼效应的双重效应项A1^*、H2^*、H3^*、A4^*。将颤振自激力进行积分运算分别求出其阻尼效应项的做功时程和刚度效应项的无功时程并从功能角度对经典耦合颤振驱动机理进行了研究,最后通过将耦合颤振微分方程转化为功能方程形式,提出了一种基于自激力瞬时做功的颤振导数识别方法并证明了该方法的可靠性。

Bridges and winds are fluid-solid interacting coupling systems.The effects of wind on bridge systems can be divided into damping effects and stiffness effects.Firstly,based on the principle of energy equivalence,the Scanlan linear flutter self-excitation is divided into pure damping effect term H1^*、A2^*,pure stiffness effect term A3^*、H4^*,and double effect term A1^*、H2^*、H3^*、A4^*with both stiffness and damping effect.The flutter self-excitation is integrated to calculate the reactive time history of the damping effect term and the stiffness effect term.The classical coupling flutter driving mechanism is studied from the functional point of view.The differential equation is transformed into a functional equation form.Moreover,and a flutter derivative identification method based on self-excited instantaneous work is proposed and the reliability of the method is proved.