基于新型LE水平跳点网格的阴阳网格平流方案设计

Designing Advection Scheme of Yin-Yang Grid Based on the New LE Horizontal Staggered Grid

为了模拟球面平流传输过程,本文基于球面阴阳重叠网格设计了一种两时间层半拉格朗日平流方案。该方案在球面坐标下采用新型的LE水平跳点网格,同时针对阴阳网格重叠区,采用了不同插值方法进行比较分析,且进行了相关的理想数值试验对方案设计效果进行评估。数值试验表明方案设计是成功的,阴阳网格重叠区平流对插值方案比较敏感;半拉格朗日方案能较好地模拟球面刚体平流和变形涡旋的结构、位置及演变过程,并具有较好的数值稳定性和较高的数值精度。

The two-time level semi-Lagrangian advection scheme is designed to study the process of global advection based on the the spherical overset Yin-Yang grid.A kind of new horizontal staggered grid named LE grid is adopted for the scheme in the spherical coordinate,and different interpolation methods have been employed to the overlapped area of the Yin-Yang grid.Besides,some idealized numerical tests are carried out.Numerical tests show that the scheme is reasonable for simulating the global advection,the advection of the overset area is obviously sensitive to the boundary interpolation schemes;the semi-Lagrangian scheme can depict the structure,position and the evolution process of solid body and deformational vortex accurately,and can get good stability and high accuracy.