NUMERICAL CALCULATION OF VORTEX-INDUCED VIBRATION OF REINFORCED THERMOPLASTIC PIPE

The dynamic model for efficiently predicting the vibration characteristics and vortex-induced vibration (VIV) response of reinforced thermoplastic pipe (RTP) is established based on Van der Pol wake oscillator model and transfer matrix method for multibody systems (MSTMM). The simulation results are compared with that of ANSYS software and experimental data, which verified the accuracy of the model. The influence of steel joints, top tension, and different inflow distribution on the VIV response of the riser is investigated. The results show that higher flow velocity may excite higher modes. The riser vortex induced vibration is mainly controlled by low-order modes. The steel joints of the riser have less influence on the wet modal of the riser. However, the influence of the VIV amplitude distribution excited by the higher-order modes as dominant vibration modes is greater. The shear flow has a great influence on the VIV amplitude distribution along the axial direction of the riser. The VIV amplitude caused by small energy at low flow velocity is smaller. However, when the shear flow velocity is enough to excite a higher-order mode of the riser, the VIV amplitude is larger than that of the uniform flow at the same flow velocity.