Numerical Simulation Method for the Rain Wind-Induced Vibration of Three-Dimensional Flexible Stay Cable at Different Wind Speeds

Rain–wind-induced vibration (RWIV) is a phenomenon of cable vibration with a large amplitude and low frequency. The RWIV involves gas, liquid, and solid phases. Therefore, it is very difficult to reproduce the RWIV by using the method of numerical simulation. In the previous research, based on the lubrication theory, researchers have established a theory model for RWIV of a rigid segment of 3D cables. Based on the previous researches, a new numerical simulation method of 3D flexible cable is proposed, which can reflect the interaction between the gas, the liquid, and the solid. The aerodynamics force is calculated by the COMSOL. The evolution of the water film is calculated by MATLAB. In the previous researches, the variation of cable shape was not considered. The cable vibration is obtained by solving the vibration equation of a 1-DOF system. In this paper, the cable is considered to generate the variation in the shape of the cable. The results of cable vibration are obtained by establishing a 3D flexible cable model in ANSYS. By using the new numerical simulation method, the RWIV phenomenon of 3D flexible cable is reproduced. The revolution of the water film, the variation of cable lift, and the cable vibration are calculated at different wind speeds. The spatial shape of cable vibration at every time is obtained. By the analysis of numerical simulation results, the mechanism of RWIV is explained again. Then, by comparing with the previous numerical simulation method, the advantage of the simulation method of RWIV of 3D flexible cable is reflected. Finally, by comparing the numerical simulation results with the results of the wind tunnel test of Gao et al., the accuracy of the simulation method of RWIV of 3D flexible cable is verified.