海洋立管两相流动及管道振动特性试验研究∗

摘要

In order to identify flow patterns that may occur in the marine riser system and study the dynamic response of the riser under different flow patterns, two⁃phase flow pressure fluctuations in the riser and resulting riser vibration displacement were tested by using an indoor testing apparatus for simulating the marine riser�In the experiment, a total of seven flow patterns are observed; time⁃frequency domain characteristic values of the pres⁃sure fluctuation and vibration response are extracted under different flow patterns�A comparative analysis is conduc⁃ted on gas⁃liquid flow characteristics and resulting riser vibration characteristics�The results show that the flow pat⁃tern in the riser can be distinguished based on time domain signal and power spectrum density characteristics; the vibration frequency of the riser is equal to that of the pressure fluctuation when the internal flow has an obvious cy⁃cle; severe slug flow Ⅰ, severe slug flow Ⅲ and hydraulic slug flow have more influences on the riser vibration;the riser has the largest displacement under the severe slug flow Ⅰ, and it has the highest vibration frequency un⁃der the slug flow.%为了识别海洋立管系统中可能出现的各个流型及考察立管系统在各流型作用下的动态响应，利用室内试验装置模拟海洋立管系统，对立管中两相流动压力波动及其引起的管道振动位移进行测试。试验中共观测到7种流型，提取了不同流型下压力波动的时频域特征值和振动响应的时频域特征值。对气液两相流流动特征及其引起的立管振动特性进行对比分析。研究结果表明，可通过时域信号结合功率谱密度特征对立管中流型进行判别；在具有明显周期性的内部流动的激励下，立管的振动频率与内部压力波动频率相等；强烈段塞流Ⅰ、强烈段塞流Ⅲ和水力段塞流对立管振动影响较大，强烈段塞流Ⅰ下立管产生的位移最大，水力段塞流下立管的振动频率最高。研究结果对保证海洋立管的安全运行具有一定的参考作用。