海岸沿岸流垂向分布实验研究

Laboratory study on the vertical distribution of longshore currents in coastal zone

进行海岸沿岸流模型实验,利用ADV(acoustic doppler velocimeter)测量了沿岸流流速沿垂直岸线方向多个断面的垂向分布。采用Faria等的方法对实验结果进行了分析,将沿岸流沿水深分为上层和下层两部分:下层采用对数分布来表达沿岸流的垂向分布;上层考虑了波浪引起的自由表面的波动,流速分布为修正的对数分布。最后对沿岸流垂向分布特征做了分析,并与Visser和Hamilton的实验结果做了对比。

The experiment was conducted to measure the vertical distributions of longshore currents.To express the velocity distribution,Faria′s method（1998） was applied.The water depth was divided into two parts： the upper layer and the lower layer.It is found from the measured data that a logarithmic profile can be used for the lower layer.Due to the presence of waves,the velocity profile for the upper layer was described by using an adjusted logarithmic profile.The characteristic of the vertical structure of the mean wave-driven longshore current was analysed and comparisons were made with Visser′s and Hamilton′s experiment to verify the results.