强制偏流喷管的三维网络生成

THREE-DIMENSIONAL GRIDS GENERATION IN FORCED DEFLECTION NOZZLES

关键词:  泊松方程  喷管气流  数值计算  格网法  固体推进剂火箭发动机

Key words:  Poisson equation  Nozzle gas flow  Numerical calculation  Grids method  Solid propellant rocket engine

摘要:

运用泊松方程实现了强制偏流喷管内的三维网络生成，方程中的源项采用了与边界形状和边界网格点分布无关的数学形式，源项内的自由参数由横向网格线与边界的交角及横向网格线在边界处的局部曲率两个约束条件来确定，实现了由边界上的网格分布直接控制内部的网格点，使生成的网格具有良好的正变性和合理性。

Abstract:

Three-Dimensional grids generation in forced deflection nozzles has been accomplished using Poisson Equations. The interior grid is controlled directly by the grid point distribution assigned on the boundaries. This is accompished by use of source terms in the Poisson Equations whose mathematical form is independent of the boundary shape and of the boundary grid POint distribution, the source terms contains free parameters evaluated locally at the boundaries using limiting forms of the elliptic equations and interpolated into the interior. Solved numerically, the elliptic system then generates an interior grid that reflects both the geometric shape of the boundary and the spatial distribution of grid points along the boundary. To obtain the three-dimensional grids, a set of six two-dimensional grids, one for each boundary surface of segment must be set up. Once the boundary values have been obtained for all faces of the computational cube, the three-dimensional grid can be generated.