Hybrid approach combining experiment and CFD numerical Simulation for rain-wind-induced vibration of a stay cable

As the aerodynamic forces are inconvenient to be measured in the wind tunnel tests of rain-wind-induced vibration (RWIV) of a stay cable under artificial simulation of rainfall, this paper presents a hybrid approach combining experiment and computational fluid dynamics (CFD) numerical simulation for RWIV of a stay cable. The stay cable (including the rivulet) and the flow field are considered as two substructures in the entire system, and the motions of stay cable and rivulet measured through wind tunnel tests are considered as known boundary condition and applied to the flow field. The flow around the moving boundary is then numerically simulated by the Fluent CFD code. First, the feasibility and precision of this approach are verified through the vortex-induced vibration of a circular cylinder, and then the approach is used to study the RWIV of the stay cable. The transient aerodynamic lift and drag coefficients are calculated and applied to a single degree of freedom model (SDOF) of the stay cable. The comparison is carried out between the oscillation responses of the SDOF model and experimental results, which indicate that the hybrid approach combining experiment and CFD numerical simulation can effectively simulate the transient aerodynamic coefficients of stay cable suffering from the RWIV.