基于贴体网格的VOF方法数模流场研究

Numerical simulation of flow field using VOF method based on body-fitted grid

提出了一种基于VOF方法的模拟具有复杂边界形状结构物附近流场的新算法,BFC-SIMPLE-VOF算法。采用坐标变换方法实现了任意复杂区域的结构化网格划分,在贴体网格下对二维不可压缩粘性流体的控制方程进行了离散。提出了基于交错网格的修正SIMPLE算法来迭代求解压力-速度场,修正了贴体坐标下的界面跟踪方法(VOF方法)。对带有弧形防浪墙的防波堤结构附近的流场和压力场进行了数值计算,并与在笛卡尔坐标网格下采用部分单元体近似描述结构物边界的原算法的计算结果进行了比较分析。

In the present study, a new algorithm-BFC-SIMPLE-VOF method based on VOF method was developed to model the flow field around the complex structures. Structured grids are achieved by the orthogonal coordinate transform method in the arbitrary complex region. The two-dimensional incompressible viscous flow was analyzed by solving Navier-Stokes equations on body-fitted curvilinear grids. The transformed SIMPLE scheme was adopted to modified the pressure-velocity field and the transformed VOF method was used to trace the free surface. The flow field and pressure field around the breakwater with curving wave wall were simulated using the new algorithm that was advanced in the paper, and was compared with the value that was achieved by the traditional rectangular grid which are approximated by steps.