将波浪作用下的振荡边界层问题化为振动平板边界层问题,利用格子Boltzmann方法中不可压缩的模型模拟了线性波和椭圆余弦波作用下的层流边界层流速变化,并和理论解进行了比较。算例表明,不同波浪条件下的数值模拟结果和理论解吻合较好,仅在流速较小的相位时两者在近床面处有较大误差,误差的形成主要与边界条件的精度有关。
The solution of oscillatory boundary layer due to waves is transformed into the solution of oscillating plate boundary layer. The velocities in the oscillatory boundary layer due to linear and cnoidal waves are simulated based on the incompressible D2Q9 model of the Lattice Boltzmann Method. The simulated results are compared with the theoretical solutions. It is shown that the results of numerical simulation agree well with the theoretical results overall at different wave conditions, though there exits large errors near bed during the phase of small velocities in the boundary layer. It is estimated that the errors are mainly caused by the low-order accuracy of the boundary condition.