针对双柱体这种极具代表性的多柱体结构，采用数值方法研究错列距离改变引起的双柱体流致振动特性的变化，分析间隙流与振动响应之间的相互影响关系。结果显示：错列双柱体的振动模态存在周期振动、双周期振动、多周期振动和拟周期振动等多种模态。上游柱体振幅受间距比的影响很小，间距比变化时，最大振动幅值均在约化速度U*=6时取得。对于下游柱体，振动幅值随间距比大幅变化，尤其是当T=0.6D（D为柱体直径）时。随着来流速度的变化，上下游柱体振幅曲线发生交叉，存在一个临界约化速度Uc*=7，当U* > Uc*时，上游柱体振幅低于下游柱体振幅。当T/D>0.6、U*<8时，为间隙流主导区。在该区域内，上游柱体脱落的漩涡形成间隙流，附着在下游柱体的表面，使下游柱体的边界层分离提前，柱体振动增强。
Aiming at two cylinders which is a very typical multi-cylinder structure, the influence of staggered distances on the flow-induced vibration response characteristics of two circular cylinders is studied using numerical simulation method. and the interaction relation between the gap flow and the vibration response of cylinders is obtained. The results illustrate that FIM mode of two cylinders include periodic vibration, double-cycle vibration, multiple-periodic vibration, and quasi-periodic vibration. With the change of staggered spacing, the amplitude of upstream cylinder is almost unaffected, and maximizes at U*=6. For the downstream cylinder, the change of staggered distance will significantly affect the trend of amplitude curve, especially when T=0.6D (D is the diameter of the cylinder). With the change of inflow velocity, the amplitude curves of upstream and downstream cylinders intersect, and there is a critical reduced-velocity Uc*=7. When U* > Uc*, the amplitude of upstream cylinder is lower than that of downstream cylinder. It is the dominant region of gap flow for T>0.6D and U* <8. In this region, vortices shed from the upstream cylinder form a gap flow, which attaches to the surface of the downstream cylinder, leading to the advance of boundary layer separation of the downstream cylinder, and enhancing the vibration of the cylinder.