在ANSYS中实现颤振时程分析的方法

Approach of time-history analysis of flutter in ANSYS

提出了一种在 ANSYS中实现颤振时程分析的有限元模型和分析方法。该模型采用 MA-TRIX2 7单元来模拟桥面主梁受到的自激力 ,依据刚度和阻尼等效的原则 ,推导了该单元的刚度矩阵、阻尼矩阵与颤振导数之间的关系 ,然后对整个系统的运动方程进行数值积分来确定系统的响应 ,通过位移时程曲线来判断结构的颤振稳定性。最后 ,以一简支梁为例介绍了在 ANSYS中颤振时程分析实现的过程 ,其分析结果与精确解。

A finite element model is presented in this paper, which can be used to perform time history flutter analysis in ANSYS. In finite element model, the MATRIX27 element is used to simulate the aeroelastic force acting on bridge deck, the relationship among stiffness matrix, damping matrix and flutter derivatives is obtained according to the principle of equivalent stiffness and equivalent damping. Then, the time history of whole structure is computed by time integration method and the flutter stability is estimated from the time history displacement.Finally, as an example,a simple supported beam is introduced to demonstrate the procedure of the analysis,and the result shows accordance with frequency domain analysis.