基于能量竞争载荷模型的海洋立管双向涡激振动时域预报方法研究

海洋立管是深海油气开发中用于连接海底井口和水面浮体的唯一通道。立管在洋流作用下极易发生涡激振动（vortex-induced vibration，简称VIV），发展快速经验性涡激振动时域预报方法对立管的安全设计具有重要意义。通过柔性立管模型试验，结合载荷重构方法和最小二乘法，识别建立了能量竞争载荷模型下的经验水动力载荷系数模型。应用识别建立的经验水动力载荷系数模型，发展形成了海洋立管顺流向及横流向双向涡激振动时域预报方法。将预报结果与试验结果对比，结果表明：基于能量竞争载荷模型的海洋立管双向涡激振动预报方法能够有效预报海洋立管涡激振动主导模态、主导频率、流向平均位移响应和涡激振动位移响应等力学行为特性。研究成果对发展更为有效的涡激振动预报手段具有有益参考。

Time-domain prediction method of bidirectional vortex-induced vibration for marine riser based on energy competition force model

Marine riser serves as the only channel to connect the subsea wellheads and offshore floating vessel in deep-sea oil and gas development. Under the action of ocean current, the riser is prone to vortex-induced vibration (VIV). It is necessary to develop the fast empirical prediction method of the vortex-induced vibration in time domain. The flexible pipe model for VIV was conducted and the empirical model of the key hydrodynamic coefficients was identified and established through the load reconstruction method and least square method. Based on the developed empirical coefficient model, the prediction method of the VIV in both in-line and cross flow directions was achieved. Comparing the present prediction result with the experimental one, it can be seen that the present method can effectively predict the dominant mode and frequency, flow-induced mean deformation, VIV displacement and other mechanical behavior characteristics of the marine riser. The present work can provide a useful reference for developing a promising vortex-induced vibration prediction method.