采用无网格方法计算含大变形介质界面的可压缩多介质流动  

Simulation of Compressible Multi-Material Flows with Large Deformation Based on Gridless Method

作　　者：王亮[1,2] 许厚谦 薛锐[1,2] 张军[3] 

机构地区：[1]南京理工大学能源与动力工程学院,江苏南京210094 [2]南京工程学院能源与动力工程学院,江苏南京211167 [3]南京航空航天大学航空宇航学院,江苏南京210016

出　　处：《北京理工大学学报》2018年第1期1-5,共5页Transactions of Beijing Institute of Technology

摘　　要：采用动态无网格节点追踪自由边界的变形,建立了一套求解可压缩多介质流场的最小二乘无网格方法.将界面定义为具有双重含义的动态无网格节点集合.使用虚拟流体方法处理介质边界节点,构造界面两侧的虚拟节点,根据介质的种类将流场划分为若干个单介质区域.为抑制界面处流动参数的非物理震荡,采用局部界面Riemann问题解更新界面节点和虚拟节点的流动参数值.使用局部点云重构技术处理界面附近的动态点云.引入AUFS格式求解ALE形式Euler方程的对流通量.一维激波管和二维复杂大变形的多介质问题计算结果证明文中提出的动态无网格法是可行的,能够准确地追踪界面的复杂变形,并对界面附近的变形点云进行合理的重构.The dynamic gridless points were used to track the complex deformation of the free movable interfaces,and the least-square gridless method for the compressible multi-material flows was developed.The material interface was treated as a series of dynamic gridless points with a dual definition.The ghost fluid method（GFM）was applied to deal with the interface points and create ghost fluid points,and the multi-material flow was divided into several independent single material flows.In order to restrain spurious numerical oscillations on material interface,the solver of the local Riemann problem on the interface was introduced into updating the flow parameters of the interface points and ghost points.Local cloud rebuilding algorithm was utilized to deal with dynamic clouds of points.AUFS scheme was extended to calculate the numerical convective flux of the Euler equations in the ALE form.The one-dimensional shocktubes problems and two-dimensional complicated problems with large deformation were simulated.The result demonstrates that the proposed gridless method is able to keep track of the material interfaces and the shock waves accurately,and makes a success of rebuilding the local deformable region.

关 键 词：无网格法 动态点云 多介质流动 虚拟流体方法 

分 类 号：O354[理学—流体力学]