径向基函数插值方法在动网格技术中的应用

分析用于非结构网格的弹簧比拟和用于结构网格的无限插值动态网格方法在实际应用中的优缺点,提出无需网格连接关系的基于径向基函数(radial basis functions,RBF)插值的动网格技术并编制相应的网格运动计算程序.以二维菱形翼的旋转运动及三维菱形翼的柔性变形为例,分析不同基函数和紧支半径的选取对网格质量及计算效率的影响,并通过与弹簧比拟方法的对比验证了RBF方法的有效性.结果表明:RBF方法数据结构简单,计算效率高,适应大变形能力强,可以有效地实现计算流体力学中的网格运动问题.

Radial Basis Function Interpolation in Moving Mesh Technique

A spring stream method used for unstructured grid and a transfinite interpolation method used for structured grid are discussed.A method using radial basis function is proposed,which resolves moving mesh problem without any grid-connectivity information.Corresponding mesh numerical program is developed.Rotation of a two-dimensional rhombic aerofoil and deformation of a three-dimensional F104 aerofoil are taken as examples to show effects of function and radius on mesh quality and numerical efficiency.Results are compared with mesh-deformation using lineal spring method.It validats availability of the RBF method.We concluded that the RBF method is remarked with simple data structure,high numerical efficiency and strong adapting ability for large mesh deformation.It could be applied to CFD dynamic mesh problems.