流场和流固耦合问题网格剖分与更新的新方法

A NOVEL TECHNIQUE FOR MESH GENERATION AND UPDATE IN THE ANALYSIS OF FLOW FIELD AND FLUID-STRUCTURE INTERACTION

基于形式代数和映射理论,针对二维/三维内外流场和流固交界面处的网格剖分问题,提出虚拟结构化映射的网格生成新方法。在虚拟规则多边形上建立虚拟网格,利用函数建立对应的映射关系,把虚拟网格映射到真实的流固边界网格上。在网格更新办法中,引入了位移映射关系,设定了流固交界面随机位移场,原流固交界面的拓扑关系和数据交换格式保持不变。分别以二维和三维管道的内部流体计算域、二维和三维建筑物体的外部流体计算域为算例,验证提出的网格生成和更新方法。统计分析表明,运用该方法可得到流体域较高质量的初始网格系统,经更新后的流体域网格质量良好,且不发生畸变。

Based on the Formex algebra and the mathematic mapping theory, a novel mesh generation technique for both two and three dimensional fluid flow field and the fluid-structure interface was presented. The virtual mesh system generated on the virtual regular polygon was mapped to the real mesh system by means of a family of the specific Formex algebraic functions. In the update technique for flow field mesh, the increment displacement mapping relationship and the reasonable random displacements along the fluid-structure interface were introduced, while the topology and data exchange format on the fluid-structure interface remained unchanged. Finally, some two/three dimensional interior and exterior flow fields were computationally investigated to verify the present technique and evaluate the quality of the initial and updated meshes.