用CT-VOF法在数值波试验槽中生成线性和非线性波

Generation of Linear and Nonlinear Waves in a Numerical Wave Tank Using CT-VOF Method

为渡水槽中波的模拟和传播提出了二维的数值模型.假设流动的流体为粘性、不可压缩的,并将Navier-Stokes方程和连续性方程作为控制方程.用标准的k-ε模型来模拟紊流流动;用交错网格的有限差分法,离散化Navier-Stokes方程;并用简化的标识和单元(SMAC)方法进行求解.使用活塞型波发生器生成并传播波;数值渡水槽的端部采用敞开式的边界条件.为了证明模型的有效性,进行了一些标准的试验,如顶盖驱动的方腔测试试验、单向的常速度场试验以及干燥河床上的溃坝试验.为了论证方法的性能及其精度,将所生成波的结果与已有波理论的结果进行比较.最后,采用群集技术(CT)生成网格,并提出最佳的网格生成条件.

A two-dimensional numerical model was developed for wave simulation and propagation in a wave flume.The fluid flow was assumed to be viscous and incompressible and Navier-Stokes and continuity equations were used as governing equations.Standard k-ε model was used to model turbulent flow.The Navier-Stokes equations were discretized using staggered grids finite difference method and solved by SMAC method.Waves were generated and propagated using a piston type wave maker.An open boundary condition was used at the end of numerical flume.Some standard tests such as lid-driven cavity,constant unidirectional velocity field,shearing flow and dam-break on dry bed were performed to validate the model.To demonstrate the capability and accuracy of the present method,the results of generated waves were compared with available wave theories.Finally,clustering technique（CT） was used for mesh generation and the best condition was suggested.