A deep analysis was implemented on the distortion of space grid edge as well as the crossover of grid cells induced by deformation consistency problem in the structured grid motion method based on radial basis functions and transfinite interpolation (RBF_TFI). Then an improved RBF_TFI method for structured grid motion was presented in accordance to the analysis results. Firstly, the reason of deformation consistency problem in dif-ferent center selection schemes was investigated in terms of deformed grid quality, displacement errors at edge-intersection points and space grid edge distortion through the case that the HIRENASD wing model has a 30-degree rotation around the y axis. Secondly, the space grid edges connected to the solid surface are defined as boundary edges and a cubic spline interpolation is adopted to update the coordinates of the grid points on these edges. Finally, the HIRENASD example was used once again to estimate the effects of the improved RBF_TFI method. The results of grid deformation show that the improved RBF_TFI method can remove the distortion of space grid edges caused by deformation consistency problem and avoid generating deformed grid cells with crossover and negative volume.%针对径向基函数插值和超限插值的结构网格运动方法(RBF_TFI)中变形一致性问题引起的空间网格棱线扭曲和网格单元交叉现象进行深入分析,并依据分析结果提出一种改进的RBF_TFI结构网格运动方`法.首先基于HIRENASD机翼模型计算网格绕y轴旋转30°的算例,从变形网格质量、棱线交叉点位移误差与空间棱线扭曲等方面分析了不同基点选择方案中变形一致性问题产生的原因;然后将与物面相连的空间棱线定义为边界棱线,并采用三次样条插值的方式更新边界棱线上网格点的坐标.使用HIRENASD算例对文中方法的效果进行了验证,结果表明,该方法能够消除变形一致性问题引起的棱线扭曲现象,有效地避免变形网格出现交叉和产生负体积单元.
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