轴向流中细长圆柱体的简化模型及动态特性分析

A simplified model for a slender flexible cylinder subjected to axial flow and its dynamic characteristics

研究了轴向流中两端支承圆柱体的动态特性。对Modarres-Sadeghi等人建立的非线性运动微分方程进行了简化,得到细长圆柱体比较简单的非线性理论模型。利用简化后方程对系统的稳定性和屈曲、颤振等失稳现象进行了分析,其结果与Modarres-Sadeghi等人的相应结果不仅在定性趋势上完全相同,而且在一些关键分岔点(失稳点)的位置等定量数据也非常相近。

In this paper,the stability and nonlinear dynamics are studied for a slender flexible cylinder subjected to axial flow.A simple nonlinear equation of motion is obtained for the cylinder supported at both ends by simplifying the corresponding equation derived by Modarres-Sadeghi et al.The purpose of the paper is to explain,with this relatively simple nonlinear model,the flutter instability found by Paidoussis in experiment and to compare the results with those obtained by Modarres-Sadeghi et al.Using the equation simplified,numerical simulations are carried out for some dynamical behavior of the cylinder at the same parameter values given by Modarres-Sadeghi et al to compare the two results.It is shown that the present result is in good agreement qualitatively with that obtained by Modarres-Sadeghi et al,and in agreement quantitatively also for some values of bifurcation points.