近壁面柔性水翼流致弯曲扭转振动特性

Flow-induced Bending and Torsional Vibration Characteristics of Flexible Hydrofoil Near the Wall

本文针对不同翼壁距离下柔性水翼的流致弯曲扭转振动特性进行研究,讨论了翼壁距离对柔性水翼的弯扭振动响应、频率响应、水动力特性以及尾涡结构的影响。研究发现,在低折减速度时(3≤U*≤6),水翼弯曲扭转幅值很小,升阻力特性的趋势与弯曲振幅类似;在8≤U*≤12范围内,由于存在弯曲和扭转的频率“锁定”现象,弯扭振动、时均升阻力系数和升阻比发生剧烈变化,翼壁距离越大,柔性水翼锁定区间越宽。折减速度和翼壁距离越大,柔性水翼的弯曲位移和扭转角度都会增大。

In this paper,the flow-induced bending and torsional vibration characteristics of flexible hydrofoils under different wing wall distances are studied,and the influence of wing wall distance on the bending and torsional vibration response,frequency response,hydrodynamic characteristics and wake vortex structure of flexible hydrofoils is discussed.The study found that at low reduced velocities(3≤U*≤6),the amplitude of bending-torsional vibration is very small,and the trend of lift and drag characteristics is similar to that of bending amplitude;in the range of 8≤U*≤12,due to the existence of frequency“lock-in”phenomenon of bending and torsion,at this time,the bending and torsional vibration,the time-average lift-drag coefficient and the lift-drag ratio change drastically,and the larger the wing wall distance,the wider the lock-in range of the flexible hydrofoil.The bending displacement and torsion angle of the flexible hydrofoil will both increase as the reduced velocity and wing wall distance increase.