参激振动对顺应式垂直通路立管涡激振动的影响

顺应式垂直通路立管(CVAR)是目前处于研究阶段的一种新型的立管类型，在海流作用下产生涡激振动，在平台垂荡运动作用下产生参数激励振动。为了研究参数激励的影响，本文引入尾流振子模型模拟漩涡脱落对立管的作用，同时考虑浮式平台升沉运动产生的参数激励，建立了CVAR参激-涡激联合振动方程，获取联合作用下的动力响应，并与纯涡激振动响应进行对比。结果表明，在相同的流速下CVAR中部涡激振动幅值最大，流速的增大会导致涡激振动的频率增大，发生高阶锁振，高阶锁振振动幅值比低阶锁振振动幅值小。考虑参数激励之后，较纯涡激振动而言，立管的振动幅值增大；当参激频率与涡激振动频率接近时，立管的振动幅值最大。

Study on the Influence of Parametric Vibration on Vortex-induced Vibration of Compliance Vertical Access Riser

The compliant vertical access riser (CVAR) is a new type of riser that is current in the research stage. It generates vortex-induced vibration (VIV) under the currents and generates parametric excitation vibration under the action of platform heave. In order to study the effect of parametric vibration on the VIV, the wake oscillator model is introduced to simulate the effect of vortex shedding. At the same time, considering parametric excitation generated by the heave motion of platform, the dynamic response of the CVAR under the parameter-vortex induced vibration is obtained, which compared with the pure VIV response. The results show that the amplitude of VIV in CVAR is the largest at the same flow rate and the increase of flow velocity will increase the frequency of VIV and high-order lock-in vibration occurs. The amplitude of high-order lock-in vibration is smaller than that of low-order vibration. After considering the parametric excitation, the vibration amplitude of the riser increases with respect to the pure VIV; when the parametric excitation frequency is close to the VIV frequency, the vibration amplitude of the riser is the largest.