适用于临近空间飞行器大变形的动网格策略

Moving mesh strategy for large deformation of near-space aircrafts

对于超大展弦比构型的低速临近空间飞行器而言,由于其在飞行过程中结构变形非常显著,因此基于计算流体力学的分析方法对于动网格提出了非常高的要求。为此,提出了一种适用于边界大变形的动网格策略,该种动网格基于映射的思想,将边界网格的位置变化以某种权重反映到流场网格,并更新网格节点位置。选取距离倒数的n次方作为权重,研究不同的权重指数n对网格变形的影响规律,然后开展了二维与三维动网格实例分析。结果表明,这种动网格方法能够很好地适用于大变形的情形,并能很好地保证变形后的网格质量。

The high-aspect-ratio low-speed near-space aircrafts may undergo very large deformation during flight, so a high demand of moving mesh is required for the analysis method based on computational fluid dynamics. To this end, a moving mesh strategy for large deformation of the boundary was presented. The strategy which is based on the mapping interpolation method reflects the displacement of boundary mesh to flow field mesh using a certain kind of weight and then updates the position of mesh nodes. Inverse distance＇ s nth-power was chosen as the weighting factor and the influence of different weight index n on the mesh deformation was studied, then the analysis of some two-dimensional and three-dimensional moving mesh cases was carried out. The results suggest that this method is capable of handling the large deformation and ensuring the quality of deformed mesh.