Study on the vortex-induced vibration response of staggered double cylinders: a numerical analysis

Abstract

Offshore multi-cylinder structures are affected by upstream wakes, shear-layer coupling, and vortex shedding, causing downstream-cylinder responses distinct from those of an isolated cylinder. This study numerically examines vortex-induced vibration of staggered double cylinders at Re=200, m*=2, ζ=0, L/D=3, α=30°, 45° and 60°, and Ur=2–12. Response curves, vorticity fields, and trajectories show that small staggered angles strengthen wake impact between cylinders, moderate angles intensify shear-layer coupling and wake deflection, and large angles induce wake stretching and multi-loop trajectory. The results clarify the interaction mechanism of wake disturbance–vortex structure–trajectory evolution and can support vibration-reduction design for staggered cylindrical structures.