Vortex-Induced Dynamic Response of Submerged Floating Tunnel Tether Based on Wake Oscillator Model
To study the vibration response of submerged floating tunnel tether under the combined action of vortex-induced vibration and parametric vibration, a non-linear vibration equation based on wake oscillator model is set up taking the geometric nonlinearity of tether into account, in which effect of tube on tether is simplified as axial excitation. An approximate numerical solution of planning submerged floating tunnel tether is obtained by applying Galerkin method and Runge-kutta method. The variation degree of mid-span displacement response and axial force of tether is analyzed when the vortex-induced resonance and parametric resonance occur. The results show that, when vortex-induced resonance and parametric resonance occur simultaneously, the mid-span displacement and axial force of tether increase dramatically; the tether sag effect results in the asymmetry of tether mid-span vibration amplitude.