Numerical analysis of flow-induced nonlinear vibrations of an airfoil with three degrees of freedom
Numerical analysis of flow-induced nonlinear vibrations of an airfoil with three degrees of freedom
复制标题
DOI：
10.1016/j.compfluid.2011.05.004
复制
发表时间：
2011-10
影响因子：
2.8
通讯作者：
M. Feistauer;J. Horáček;M. Ruzicka;P. Sváček
中科院分区：
文献类型：
--
作者：
M. Feistauer;J. Horáček;M. Ruzicka;P. Sváček
本文的主题是二维不可压缩粘性流与大振幅振动翼型相互作用的数值模拟。具有三自由度的实心翼型绕弹性轴旋转、垂直方向振荡以及襟翼旋转。数值模拟包括纳维-斯托克斯方程的有限元解以及描述翼型运动的非线性常微分方程组。瞬态计算域和移动网格由纳维-斯托克斯方程的任意拉格朗日-欧拉 (ALE) 公式处理。高雷诺数需要应用适当的有限元离散稳定方法。借助数值实验，我们分析了如果计算网格细化并且时间步长逐渐减小，该方法的收敛性。还测试了流动和结构问题的松（弱）耦合和强耦合的影响。通过与 NASTRAN 计算的比较以及在颤振失稳之前和之后增加远场速度的耦合流固问题的求解，证明了该方法的适用性。所开发的方法可用于气动弹性系统动态行为的理论预测，特别是当系统失去稳定性时。
The subject of the paper is the numerical simulation of the interaction of two-dimensional incompressible viscous flow and a vibrating airfoil with large amplitudes. A solid airfoil with three degrees of freedom performs rotation around an elastic axis, oscillations in the vertical direction and rotation of a flap. The numerical simulation consists of the finite element solution of the Navier–Stokes equations coupled with a system of nonlinear ordinary differential equations describing the airfoil motion. The time-dependent computational domain and a moving grid are treated by the arbitrary Lagrangian–Eulerian (ALE) formulation of the Navier–Stokes equations. High Reynolds numbers require the application of a suitable stabilization of the finite element discretization. With the aid of numerical experiments we analyze the convergence of the method, if the computational mesh is refined and the time step is successively decreased. Also the effect of the loose (weak) and strong coupling of the flow and structure problems is tested. The applicability of the method is demonstrated by the comparison with NASTRAN computations and the solution of the coupled fluid–structure problem with increasing far-field velocity up to and behind the flutter instability. The developed method can be used in theoretical prediction of dynamic behaviour of aeroelastic systems especially when the system stability has been lost.