窝崩具有时间短、破坏大的特点，在我国河流中较为普遍突出。大量研究表明，窝崩过程的主要影响因素是水动力学条件，特别是伴随窝塘所产生的次生流剪切应力和紊动应力。但是，目前尚无关于二者作用机理的力学研究。项目拟建立可精确计算水流紊动和边壁切应力的崩岸三维数学模型。模型利用大涡模拟，可准确计算涡崩过程水流的紊动相干结构；利用数值单元切割法，可准确追踪拟合窝崩过程滩岸的动态变化过程，从而可以准确计算崩岸过程的剪切应力。利用窝塘紊动玻璃实验水槽和窝崩概化水槽实验，对数学模型进行了参数率定和验证。在模型验证合理的基础上，对不同控制节点和水流条件下窝崩过程进行模拟，研究窝崩过程中的详细作用机理，给出不同条件下窝崩演化趋势以及最佳抛石防治措施。

Ω-shaped bank collapse is very common in Chiese rivers. Many investigation have showed that hydrodynamic action is the main cause of the collapse, of which the shearing stress of secondary flow and turbulence plays the dominant role. But no study has been carried to study its mechanism. In this project，3D-dimensional sedimental numerical model is established,in which cut-cell method is used to fit the boundary,and LES is used to simulate the coherent structure of the turbulence.Two pysical models are carried out for the calibration of the numerical model,in which the smaller is used for the calibration of turblence and and the larger is used for the calibration of bank-collapse process. Based on the numerical models, shearing stress on the bank and the turbulence intensity in the whole process of the bank collapse can be abtained, and the hydrodynamic mechanism of the bank collapse is studied,which can help to predict the properbility of the Ω-shaped bank, and to decide the best controling meassure.