方柱绕流诱发的弹性薄板流固耦合特性研究

NUMERICAL INVESTIGATION OF FLUID-STRUCTURE INTERACTION OF THIN ELASTIC PLATE IN WAKE FLOWING FIELDS

在封闭水流槽道中央,上游布置一刚性方柱,下游弹性薄板的一端固定在方柱尾端,弹性薄板上端、下端和另一端自由。上游方柱绕流后在下游形成周期性扰动流场,进而诱发下游弹性薄板的连续振动。数值模拟结果表明,当周期性扰动流场与结构形成强烈的非线性耦合作用时,近壁区流动进一步受板扰动的影响,流动的边界条件发生改变,流场对称结构遭到破坏,形成不同尺度的涡旋流动,同时弹性薄板表现出非周期、非对称的耦合振动行为。

A fixed square rigid body is submerged in water flowing,a thin elastic plate is attached to the rigid body in the centre of the downstream face.The vortices,which separate from the corners of the rigid body,generate periodic lift forces which excite continuous vibrations of the thin elastic plate.Numerical simulation on fluid-induced vibration of thin elastic plate was carried out.The results reveal that,on the one hand,the swirling flow of different scales comes into being due to the eddy shedding upstream and the disturbance of plate vibration downstream,on the other hand,the fluid-induced vibration is quite significant for wake flowing fields and the elastic plate shows a non-periodic and an asymmetric coupled vibrating behavior when the complex wake interacts with the plate.