涡激振动（VIV）广泛存在于自然界与工程应用，历来是流体力学的热点问题之一。本项目拟采用数值模拟、实验观测并结合理论分析研究长方柱与椭圆柱等具有细长截面的柱状振子在一种新型VIV系统：泊肃叶流致振动（PFIV）中的动力学行为及其响应机理。相对于弹性体VIV，PFIV的主要特征是柱体振动由尾流脱落涡与槽道壁面限制，而非与结构固有弹性，相互作用所激发。研究旨在探索与阐明：（1）层流区、过渡区和湍流区PFIV中柱体运动与涡脱落模态特性及各流动区域响应模态形成与转捩机制；（2）临界质量比现象发生机理及其理论预报模型；（3）PFIV与弹性体VIV诱发机制的内在关联。.项目的实施不仅能够揭示PFIV深层次发生机理，而且有助于深入认识VIV本质，具有重要的理论意义。同时，大振幅高质量比振子的获得和模型系统的实验室实现，为设计依据PFIV机制的高效混合器和换热器提供新的思路与科学依据。

Vortex-induced vibration (VIV) which exists extensively in nature and engineering, is a hot issue in fluid mechanics constantly. This project is to research the dynamic behaviors, as well as the response mechanisms, of a rectangular or elliptical cylindrical oscillator in a novel VIV model system, named the Poiseuille flow-induced vibrations (PFIV) by numerical simulation, experimental investigation, in combination with the theoretical analysis. A significant characteristic of the present PFIV model system is that the cylinder oscillation is excited by the interaction between shedding vortices and channel wall confinement, rather than by the interaction of shedding vortices and structural elasticity for the classic VIV of an elastic structure. The main purpose of this project is to explore and clarify: (1) The characteristics of cylinder motions and vortex shedding modes for PFIV in laminar, transition and turbulent regimes and the mechanisms for the excitations and transitions of response modes in different flow regimes. (2) The mechanism for the phenomenon of critical mass ratio and the theoretical prediction model for critical mass ratio. (3) The intrinsic connections of the inducement mechanisms between PFIV and VIV of an elastic structure. .The present project will be helpful to a comprehensive understanding of the internal mechanism of the present PFIV model system, as well as the intrinsic nature of VIV. The obtention of large-amplitude oscillator with high mass ratio and the production of PFIV in laboratory, will provide new ideas and scientific basis in designing a fluid mixer or a heat transmitter based on PFIV.