计算含大位移动边界非定常流动的无网格算法  

THE MESHLESS METHOD FOR UNSTEADY FLOW WITH LARGE-SCALE MOVING BOUNDARY

作　　者：周星[1] 许厚谦[1] 

机构地区：[1]南京理工大学动力工程学院,南京210094

出　　处：《力学与实践》2010年第6期8-12,42,共6页Mechanics in Engineering

摘　　要：研究了可以计算处理包含大位移动边界非定常流动的无网格算法.创建了无网格方法中由于大位移边界运动造成的不合要求点的判断标准,采用高效的填充方法实现点云重构,运用线性插值方法得到新点参数,实现了局部重构处理大位移动点.流场计算方面,在计算域自动布点基础上,采用曲线逼近计算导数及HLLC格式计算数值通量,发展了求解基于无网格的ALE方程组的算法.最后,对活塞问题进行了模拟,结果与解析解相吻合,验证了算法的准确性;另外,计算比较了气流流过静止圆柱以及圆柱在静止流场运动流场,结果表明方法是成功的.The meshless method for unsteady flow involving large-scale moving boundaries is studied in this paper.A criterion for whether the point is to be deleted is established,the cloud is rebuilt by a filling method,and the state of the new point is calculated by a linear interpolation method,which serves as the local reestablishment of cloud for dealing with large scale moving points.The algorithm for solving ALE equations based on the meshless method is developed.On the basis of clouds,the spatial derivatives are approximated by using local least-squares curve fitting and the numerical flux is calculated with HLLC scheme,and a multistage Runge-Kutta algorithm is used to advance the equation in time.As an example,a moving piston is simulated,and the numerical results agree well with exact results.In addition,the flow of airflow passing through a static column and the flow of a column moving in the static flow are simulated and compared with each other,and results indicate that the method is valid.

关 键 词：无网格 点云重构 ALE方程 运动边界 数值模拟 

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]