高阶Godunov格式的SPH方法及超高速碰撞中的应用

项目名称： 高阶Godunov格式的SPH方法及超高速碰撞中的应用

项目编号： No.10802097

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 武器工业

项目作者： 徐志宏

作者单位： 中国人民解放军国防科学技术大学

项目金额： 26万元

中文摘要： 光滑粒子流体动力学方法作为一种纯Lagrange无网格算法，在计算大变形等问题中具有特殊的优势。针对传统光滑粒子方法中的计算精度低和不稳定现象，本项目在用黎曼解来描述粒子间的相互作用的基础上，对光滑粒子方法进行改进，采用改进的方法对超高速碰撞现象进行数值模拟，并初步建立起数值模拟的风险评估体系。研究内容包括：（1）将二阶Godunov格式和Taylor展开引入光滑粒子方法，建立高精度的高阶Godunov格式的光滑粒子方法；（2）采用高阶Godunov格式光滑粒子方法，引入GRAY三相物态方程对超高速碰撞碎片云团进行数值模拟并研究碎片云团的动力特性；（3）构造数据之间的灰色关联度或图像的几何关联模型，建立量化的数值模拟科学评估体系。本项目所取得的成果可以为开发具有自主知识产权的超高速撞击数值模拟软件提供技术支持。

中文关键词： 光滑粒子方法；Godunov格式；超高速碰撞；碎片云团；评估体系

英文摘要： Smoothed particle hydrodynamics (SPH) is a fully Lagrangian particle method, which uses no background spatial mesh. Since there is no mesh to distort, the method seems ideally suited to handle the large deformations problems. To improve the solution accuracy around the boundary effectively and reduce the instability both in tension and compression, a modified contact algorithm based on the interparticle contact method to remedy some weakness of the standard SPH method is proposed, and which is to simulate the hypervelocity impact problems. Besides, a assessment system of numerical simulate is studied. The primary contents are: (1) A modified SPH method with high accuracy based on second-order Godunov-scheme and Taylor series is built. (2) Together with the new method, GRAY equation of state is used to simulate the hypervelocity impact and the characteristics of debris cloud are investigated as well. (3)Construct the gray relationship of the data, or the geometry model of the image association to build an assessment system of numerical simulation. The results of this project will provide technical support for the development of hypervelocity impact numerical simulation software with independent intellectual property.

英文关键词： smoothed particle hydrodynamics; Godunov-cheme; hypervelocity impact; debris cloud; assessment system