The flow-induced vibrations (FIV) in two degrees of freedom for two circular cylinders with three arrangements including parallel, tandem, and stagger were investigated numerically, the rigid constraint is considered due to its widespread in industry fields. The effects of arrangement and constraint on FIV characteristics, including trajectory, vibration response, force response, and near wake structure, are analyzed. Results indicate that the existence of constraint can significantly suppress the vibration of the two cylinders when reduced velocity U*<7. However, when U*≥7, the oscillation of the parallel cylinders with constraint in cross-flow direction is strengthened. Moreover, the existence of constraint can reduce the vibration frequencies of cylinders with tandem arrangement significantly. The trajectory in the shape of “8” can be captured in most cases of motion for the cylinders without constraint. And the closed single-loop, “8”, and “I” shape trajectories are obtained for the vibration of cylinders with constraint. The two cylinders move synchronously when the constraint is applied, and the near wake structures of the two cylinders are more stable than that without constraint.

数值研究了两个平行，串联和错位三种布置的两个圆柱体在两个自由度上的流致振动（FIV），由于其在工业领域中的广泛应用，因此考虑了刚性约束。分析了布置和约束对FIV特性的影响，包括轨迹，振动响应，力响应和近尾结构。结果表明，当减小的速度U * <7时，约束的存在可以显着抑制两个气缸的振动。但是，当U*≥7，加强了在横流方向受约束的平行圆柱体的振动。此外，约束的存在可以显着降低串联布置的气缸的振动频率。在大多数情况下，气缸运动时可以不受限制地捕获形状为“ 8”的轨迹。并针对约束气缸的振动获得了闭合的单回路，“ 8”和“ I”形轨迹。当施加约束时，两个汽缸同步运动，并且两个汽缸的近尾流结构比没有约束的情况更稳定。