基于多块对接网格的隐式气体运动论统一算法应用研究  

AN APPLICATION OF IMPLICIT GAS-KINETIC UNIFIED ALGORITHM BASED ON MULTIBLOCK PATCHED GRID

作　　者：彭傲平[1] 李志辉[1,2] 吴俊林[1] 蒋新宇[1] 

机构地区：[1]中国空气动力研究与发展中心超高速所,四川绵阳621000 [2]国家计算流体力学实验室,北京100191

出　　处：《力学学报》2016年第1期95-101,共7页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家重点基础研究发展计划(2014CB744100);国家杰出青年科学基金(11325212);国家自然科学基金(91016027)资助项目

摘　　要：基于玻尔兹曼模型方程的气体运动论统一算法(gas kinetic unified algorithm,GKUA)给出了一种能模拟从连续流到自由分子流跨流域空气动力学问题的途径.该算法采用传统计算流体力学技术将分子运动和碰撞解耦处理,若采用显式格式将受格式稳定条件限制,在模拟超声速流动尤其是近连续流和连续流区的流动时计算效率较低.为了提高计算效率,扩展其工程实用性,采用上下对称高斯-赛德尔(LU--SGS)方法和有限体积法构造了求解玻尔兹曼模型方程的隐式方法,同时在物理空间采用能处理任意连接关系的多块对接网格技术.通过模拟近连续过渡区并排圆柱绕流问题,计算结果与直接模拟蒙特卡洛方法模拟值吻合较好,验证了该方法用于跨流域空气动力计算的可靠性与可行性.Gas Kinetic Unified Algorithm （GKUA） based on Boltzmann model equations is proposed for simulating aero- dynamics problems covering various flow regimes. In this algorithm, molecular motions are decoupled from collisions by traditional Computational Fluid Dynamics methods, so that the calculation efficiency would be quite low at the limitation of stabilization condititns of explicit schemes when simulating supersonic flows especially which are near-continuum and continuum flows. In order to improve the efficiency and expand engineering practicability, an implicit method for Boltzmann model equations is constructed by using LU-SGS （Lower-Upper Symmetric Gauss-Seidel） method and cell- centered finite volume method, and multi：block patched grid technique is used in physical space. The present computed results of two side-by-side cylinders in transitional flow regime are found in good agreement with those from Direct sim- ulation Monte-Carlo method simulation~ The dependability and feasibility for simulating problems covering various flow regimes by the present method are validated.

关 键 词：气体运动论统一算法 隐式格式 多块对接网格 有限体积法 跨流域空气动力学 

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]