通过物理模型实验以及数值方法研究了沿岸流不稳定运动对时均沿岸流的影响.首先简要介绍了沿岸流不稳定运动测量实验并给出了测量结果;然后建立了考虑沿岸流不稳定运动的数学模型,该模型中引入了沿岸流不稳定运动引起的辐射应力项,为了使数值分析与实际情况相吻合,该模型中考虑沿岸流不稳定运动引起的辐射应力由实验中观测到的结果求得.利用求得的应力项,粗略分析了沿岸流不稳定运动引起的侧混系数的范围,结果表明该范围为0~0.04.利用该模型数值分析了沿岸流不稳定运动对时均沿岸流的影响,结果表明其影响很小.
The effects of instability of longshore currents on the mean longshore currents were investigated by physical modeling and numerical method.Firstly,the experiments for measuring instability of longshore currents were introduced and experimental results were given.Then,the mathematical model including the instability of longshore currents was built.In the model,the radiation stress due to the instability of longshore currents was calculated using the measurement velocity time series in order to simulate the real situation well.At the same time,the lateral mixing coefficient caused by instability of longshore currents was obtained.The coefficient is approximately 0-0.04.The effects of the longshore currents instability on the mean longshore currents were analyzed using the presented model.The analytical results show that the effects of the longshore currents instability on the mean longshore currents are small.