Flutter analysis of an airfoil with nonlinear damping using equivalent linearization

作     者：Chen Feixin Liu Jike Chen Yanmao 

作者机构：Department of MechanicsSun Yat-sen University 

出 版 物：《Chinese Journal of Aeronautics》 (中国航空学报（英文版）)

年 卷 期：2014年第27卷第1期

页      面：59-64页

核心收录：

学科分类：08[工学] 0825[工学-航空宇航科学与技术] 

基　　金：supported by the National Natural Science Foundation of China (Nos.:11002088 11172333 11272361) 

主　　题：Airfoil flutter Bifurcation Cubic damping Equivalent linearization Limit cycle oscillation 

摘      要：The equivalent linearization method （ELM） is modified to investigate the nonlinear flut- ter system of an airfoil with a cubic damping. After obtaining the linearization quantity of the cubic nonlinearity by the ELM, an equivalent system can be deduced and then investigated by linear flut- ter analysis methods. Different from the routine procedures of the ELM, the frequency rather than the amplitude of limit cycle oscillation （LCO） is chosen as an active increment to produce bifurca- tion charts. Numerical examples show that this modification makes the ELM much more efficient. Meanwhile, the LCOs obtained by the ELM are in good agreement with numerical solutions. The nonlinear damping can delay the occurrence of secondary bifurcation. On the other hand, it has marginal influence on bifurcation characteristics or LCOs.