Vortex-induced vibration (VIV) of an elastically supported disk is investigated computationally using large-eddy-simulation (LES). The disk motion is constrained to move in the transverse plane vertical to the free stream. Two sets of simulations are conducted at $Re=165$ and 210 over the reduced velocity range $3\le {\mathit{U}}_R\le 7.5$ respectively. The disk shows a highly periodic large-amplitude vortex-induced vibration response over a certain reduced velocity range at both Reynolds numbers. The shedding of intertwined longitudinal spiral vortex in the wake of a vibrating disk is investigated for the first time in this paper. Moreover, we find a new wake mode named unsteady spiral (US) mode in the present work for a vibrating disk, except for reflectional-symmetry-breaking (RSB) mode and standing wave (SW) mode for a stationary disk. Our researches show the wake mode is not only related to the Reynolds number, but also to the vibration of the disk. When the wake is in the RSB mode, the disk moves along a linear path in the transverse plane, while the disk vibrates along a linear path under the SW mode, and the disk path is a perfect circle under the US mode. The transformation process from quasi-8-shaped trajectory to linear trajectory and from linear trajectory to circular trajectory are also presented and investigated.

使用大涡模拟（LES）在计算上研究了弹性支撑盘的涡激振动（VIV）。盘的运动被限制为在垂直于自由流的横向平面中运动。进行了两组模拟$\mathrm{[R}Ë=165$ 和210在降低的速度范围内 $3\le {\mathit{ü}}_{\mathrm{[R}}\le 7。5$分别。在两个雷诺数下，圆盘在一定的减小的速度范围内均表现出高度周期性的大振幅涡激振动响应。本文首次研究了在振动盘尾部缠绕在一起的纵向螺旋涡流。此外，我们在振动磁盘的当前工作中发现了一种新的唤醒模式，称为非稳态螺旋（US）模式，除了固定磁盘的反射对称破坏（RSB）模式和驻波（SW）模式之外。我们的研究表明，唤醒模式不仅与雷诺数有关，而且与磁盘的振动有关。当尾波处于RSB模式时，磁盘在横向平面中沿线性路径运动，而在SW模式下磁盘沿线性路径振动，而在US模式下磁盘路径是理想圆。