The Effect of the Layout of a Rigid Splitter Plate on the Flow-Induced Vibration of a Downstream Cylinder Subjected to Wake Flow

In this study, the effect of additional positions of rigid splitter plates on the response characteristics of tandem cylinders at a Reynolds number of 150 and a fixed distance ratio of 5.0 was numerically investigated via the computational fluid dynamics (CFD) method. Four layouts for the cylinder-plate body, including a downstream cylinder (DC), a downstream cylinder-plate body with a wake side plate (DCP), a downstream plate-cylinder body with an incoming flow side plate (DPC), and a downstream plate-cylinder-plate body with a double-sided plate (DPCP), are considered. The results show that the splitter plate attached to the incoming flow side or the wake side can suppress the vibration of the downstream cylinder in a specific reduced velocity range (4.0 < U-r <= 10.0). Compared with the DC, the maximum response amplitude of the DPC and DCP in the lock-in region is reduced by 30.8% and 47.4%, and the lock-in bandwidth is also significantly narrower. The layer separation point of the upstream cylinder moves downstream upon adding splitter plates to both the incoming flow and wake sides, and the resulting splitter shear layer of the DPCP is completely parallel to the free flow, while the maximum response amplitude is reduced by 93.6%, which realizes the best effect of stream-induced vibration suppression.