基于自适应笛卡尔网格的飞翼布局流动模拟  

Simulation of flow around fly-wing configuration based on adaptive Cartesian grid

作　　者：陈浩 华如豪 袁先旭[1,2] 唐志共[2] 毕林[1,2] CHEN Hao;HUA Ruhao;YUAN Xianxu;TANG Zhigong;BI Lin(State Key Laboratory of Aerodynamics,China Aerodynamics Research and Development Center,Mianyang 621000,China;Computational Aerodynamics Institute,China Aerodynamics Research and Development Center,Mianyang 621000,China)

机构地区：[1]中国空气动力研究与发展中心空气动力学国家重点实验室,绵阳621000 [2]中国空气动力研究与发展中心计算空气动力研究所,绵阳621000

出　　处：《航空学报》2022年第8期388-399,共12页Acta Aeronautica et Astronautica Sinica

基　　金：国家数值风洞工程;空气动力学国家重点实验室创新基金。

摘　　要：小展弦比飞翼布局具有较好的隐身和气动性能,是未来战机的先进布局。对飞翼飞机进行CFD数值模拟时,其全翼式设计使得高质量贴体网格的生成存在一定的难度。相比之下,自适应笛卡尔网格方法具有自动化和高质量兼顾的优势。本文对自适应笛卡尔网格技术进行发展,并开展小展弦比飞翼布局的数值仿真研究。采用全线程树笛卡尔网格数据结构,结合改进后的网格单元类型判断方法,以及基于几何特征和流场解特征的自适应方法,并通过虚拟层技术优化近壁网格,发展了高效、鲁棒、高质量的三维自适应笛卡尔网格生成技术;对于非贴体物面边界的处理,发展了基于浸入边界方法思想的虚拟单元重构技术,构造了高保真的非贴体笛卡尔网格边界条件;针对黏性流动控制方程,发展了笛卡尔网格框架下的数值离散方法,建立了适用于自适应笛卡尔网格的Navier-Stokes方程数值求解器;基于上述工作,开展了自适应笛卡尔网格技术在小展弦比飞翼布局低速流动问题中的应用研究,证明了本文所发展的技术方法的可靠性,并探究了自适应技术对于流场特征和气动力特性的影响作用。The fly-wing configuration with low aspect ratio has better stealth and aerodynamic performance,and therefore,is the advanced configuration of future fighter.In CFD simulation of fly-wing aircraft,the full wing design makes it difficult to generate high quality body-fitted grids.In contrast,adaptive Cartesian grid method has the advantages of automation and high quality.In this paper,the adaptive Cartesian grid technology is developed,and the numerical simulation of fly-wing configuration with low aspect ratio is carried out.Firstly,combining the improved method of determining the grid cell type with the adaptive method based on the geometric characteristics and flow field solution characteristics,a highly efficient,robust and high-quality three-dimensional adaptive Cartesian mesh generation technology is developed by using the fully threaded tree Cartesian mesh data structure and optimizing the near wall mesh through the virtual layer technology.For the processing of non-body-fitted wall boundary,the basic method is developed based on the ghost cell reconstruction technique of immersed boundary method,and the high fidelity boundary conditions of non-body-fitted Cartesian grids are constructed.For viscous flow control equations,the numerical discretization method in the framework of Cartesian grids is developed,and the numerical solver of Navier-Stokes equations suitable for adaptive Cartesian grids is established.Based on the above work,the application of adaptive Cartesian grid technique is carried out.The application research of fly-wing configuration with low aspect ratio in low-speed flow problem proves the reliability of the technical method developed in this paper,and deeply explores the influence of adaptive technology on flow field characteristics and aerodynamic characteristics.

关 键 词：飞翼 笛卡尔网格 浸入边界方法 非贴体 自适应技术 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]