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在长江口区主航槽中利用悬浮物浓度测定系统（ＡＣＰ１） 第一次获得了近底紊流“猝发”（ｂｕｒｓｔ） 和床面泥沙喷发（ｅｊｅｃｔｉｏｎ） 的连续时间序列可视图像和数据，同时利用高分辨率流速仪以及旁侧声纳、热敏式双频测深仪等手段获得了大量底形沙波的实测图像和数据。这些图像和数据结果表明：长江口南支南港之间粗粉砂至极细砂在涨落潮流的作用下，呈现静止———细颗粒泥沙起、悬扬———粗颗粒喷发运移的同时进行大尺度底形运动—细颗粒起扬、悬扬—静止的输移循环模式，即当Ｕ＜ ５０ｃｍ／ｓ，泥沙在底床上基本不运动；５０ｃｍ／ｓ＜ Ｕ＜ ６５ｃｍ／ｓ，小尺度紊流猝发发生，泥沙开始小尺度起扬，并有幕式猝发现象；６５ｃｍ／ｓ＜ Ｕ＜ １００ｃｍ／ｓ 时，小尺度紊流猝发强度和持续宽度急剧增大，床面细颗粒泥沙开始喷发导致床面开始冲淤，形成中小尺度沙波；１００ｃｍ／ｓ＜ Ｕ＜ １１０ｃｍ／ｓ 时，大尺度紊流形成，床面粗颗粒泥沙开始喷发；到了Ｕ＞ １１０ｃｍ／ｓ 时，宏观紊流规模更大，床面粗颗粒泥沙的喷发强度和持续宽度急剧增大，导致床面形成大尺度沙波运动。由于 Ｕ＞ １１０ｃｍ／ｓ的落潮流速远远大于涨潮流速，且落潮最大流速达１３７ｃｍ／ｓ，落急（ 流速＞ ?
In the main navigation channel of the Yangtze River Estuary, continuous time series visual images of near-surface turbulence “burst” and bed sediment ejection were obtained using the system for determination of suspended matter concentration (ACP-1) And data. At the same time, a large number of measured sand wave data and data were obtained by means of high-resolution velocity gauges, side sonar and thermal double-frequency depth sounder. The results of these images and data show that the coarse silt to very fine sand between Nanzhan and Nangang of the Yangtze Estuary is still-suspended sediment and suspended sediment due to the fluctuation of tidal flow While the large-scale bottom-shaped movement - fine particles from Yang, suspended Yang - static transport cycle mode, that is, when U <50cm / s, sediment in the bed basically does not exercise; 50cm / s 110cm / s , The macroscopic turbulence is larger and the eruption intensity and continuous width of coarse bed sediment increase sharply, resulting in the formation of large-scale sand wave motion on the bed. Because U> 110cm / s ebb flow rate is far greater than the tidal flow rate, and the maximum ebb flow rate of 137cm / s, urgent (flow rate?