南海内波监测预警技术研究与应用

Research and application of internal wave monitoring and warning technology in South China Sea

南海深水内波发生极其频繁,曾观测到振幅达150 m、流速达2.5 m/s的内波,其剪切流对经过区域的海洋工程结构物破坏力极大,严重威胁海洋油气工程作业安全。通过分析南海历史内波多发区域、季节、重现周期及传播途径,在目标海域布设由1套潜标和2套浮标组成的监测系统,在为期一年的监测周期内成功捕获多个内波发生时的信号参数,如与内波伴生的内潮波和内孤立波振幅、模态及传播速度等数据,得出监测到的内波振幅变化在30~110 m之间,最大垂向剪切流速为1.6 m/s左右。监测数据通过卫星及时传输,为深水半潜式平台作业提供了内波预警,确保了平台持续安全生产。基于研究结果表明,该实时连续的深水内波监测预警技术可作为保障海洋工程安全作业的重要手段之一。

The deepwater internal waves occur very frequently in the South China Sea,an internal wave with the amplitude of 150 m and the flow velocity of 2.5 m/s has been observed.Its strong shear flow destructs the offshore structures greatly while passing the region,and threatens seriously the operation safety of offshore oil and gas engineering.After analyzing the characteristics of the region,seasons,recurrence cycles and transmission routes in the internal waves history in the South China Sea,the monitoring system including one set of submarine observation system and two sets of buoy observation systems was deployed in the target region.The signal parameters such as the amplitude,mode and propagation velocity of internal tidal waves and internal solitary waves were captured successfully during the one-year period monitoring operation.The variation of amplitude was between 30~110 m and the maximum vertical shear velocity was about 1.6 m/s.The monitoring data were transmitted timely via satellite to ensure safe operation of the deepwater semi-submersible platform.It is concluded that the real-time and continuous observation and early warning technology for deepwater internal waves can be used as an important means to ensure the safe operation of offshore engineering.