基于声传播时间的二维流场反演数值仿真研究

Numerical simulation study on inversion of two dimensional flow field using acoustic ray travel time

基于南海1998年夏季调查航次诊断计算的流函数场,选取越南以东偶极子发生海域,进行不同的声层析观测站位设置实验。模拟计算声线传播时间信息,然后应用基函数重建方法进行了流函数场的模拟反演研究,讨论了不同随机观测误差对反演结果的影响。研究结果表明该方法是可行的,在所选取的约833 km×833 km海域内,在观测海域外围配置19个声层析观测站位就能够很好地重构原流函数场,空间分辨率约为63.7 km,可以分辨模拟海域中尺度涡场结构,这是传统的基于海流计(CM)或声学多普勒剖面仪(ADCP)等观测方法所不能企及的。该观测技术和方法可以实际应用于近海大范围流场结构的遥感实时监测,为近海污染物等的扩散研究,海洋环境变化等提供实时观测流场资料。

On the basis of the stream function field computed using diagnostic model in the South China Sea during the summer 1998, in the area east to Vietnam where the dipole often occurs, the acoustic tomography observation stations were deployed. By using the acoustic ray travel time information, the inversion problem of two dimensional flow field was studied, and the affection for inversion results from random errors also been discussed. The results displays that the stream function can be restructured by inversion method using only 19 acoustic tomography observation stations in the 833 km× 833 km area. Spatial resolution is 63.7 kin, and the acoustical tomography system can monitor the area with eddy-resolving scales. The traditional observation method, such as Current Measurement（CM） or Acoustic Doppler Current Profiler （ADCP） can not do this. The observation technology and method can be used to remote monitor the flow field structure in real time, and obtain the real time data for study of coastal environmental monitor and study.