Nonlinear perturbation developments in flow around a vibrating cylinder

作     者：Jian Deng Xuerui Mao Jian Deng;Xuerui Mao

作者机构：State Key Laboratory of Fluid Power and Mechatronic SystemsDepartment of MechanicsZhejiang UniversityHangzhou 310027China Faculty of EngineeringUniversity of NottinghamNottinghamUK 

出 版 物：《Journal of Hydrodynamics》 (水动力学研究与进展B辑（英文版）)

年 卷 期：2021年第33卷第6期

页      面：1129-1138页

核心收录：

学科分类：080103[工学-流体力学] 08[工学] 080104[工学-工程力学] 081502[工学-水力学及河流动力学] 0815[工学-水利工程] 0701[理学-数学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：Projects supported by the National Natural Science Foundation of China(Grant Nos.11772299 11922212) 

主　　题：Vortex induced vibration nonlinear optimal perturbation Orr mechanism 

摘      要：We investigate the flow around a circular cylinder vibrating with a prescribed magnitude and frequency at Reynolds number *** Navier-stokes equations and the adjoint equations are solved to search for the 3-D nonlinear optimal initial perturbation,which is amplified by the attached shear via the Orr mechanism and then activates wake *** energy growth and the spanwise distributions of the nonlinear optimal perturbation vary significantly with the initial phase to introduce the *** the initial perturbation energy increases,linear amplification,nonlinear saturation and nonlinear growth are sequently *** last one is owing to the generation of a spanwise homogeneous mode,which modifies the pressure distributions on the cylinder surface and induces an extra lift ***,at all the initial phases,this force is opposite to the acceleration of the cylinder,illustrating the potential to reduce the magnitude of vibration.