三维非结构混合网格生成与N-S方程求解

Generation of Three Dimensional Mixed and Unstructured Grids and its Application in Solving Navier-Stokes Equations

提出了一套较为通用的,完全自动化的非结构混合网格生成方法,在物面粘性作用区,运用一种改进的推进层方法生成三棱柱形和金字塔形网格;在其他流动区域采用阵面推进方法生成四面体网格。采用一种改进精度的格心有限体积法和Spalart Allmaras一方程湍流模型对三维N S方程进行了求解,并以M6机翼、DLR F4翼身组合体和某运输机外形的粘性流场作为数值算例,验证了上述网格生成和流场求解方法的正确性和实用性。

A method for generating three-dimensional mixed-element-type unstructured grids and its application in simulating viscous flow by solving the Navier-Stokes equations are presented. Pirzadeh's advancing-layer method is modified to generate high-quality mixed prismatic/pyramid/ tetrahedral-element-type unstructured grids in the boundary-layer region, and the traditional advancing-front method is used to construct isotropic tetrahedral grids in the residual flow region. Based on the Spalart-Allmaras one equation turbulence model, three-dimensional Navier-Stokes equations are solved by using a cell-centered finite-volume method. Viscous flow problems around the ONERA M6 wing, a DLR-F4 wing-body configuration and a transport configuration are simulated to verify the correctness and practicability of the methods.