基于MGFM技术的可压缩无粘流体与板壳结构非线性耦合高效算法研究

项目名称： 基于MGFM技术的可压缩无粘流体与板壳结构非线性耦合高效算法研究

项目编号： No.11201442

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 许亮

作者单位： 中国航天空气动力技术研究院

项目金额： 22万元

中文摘要： 近年来发展的修正的虚拟流体方法（MGFM）为解决流固耦合问题提供了一种稳健高效的界面处理新方式，已有一些成功的应用，但针对平板或壳体这类特殊结构的问题还有待解决。本项目将通过推广近期发展的Euler-Euler框架下多介质Riemann问题技术到Euler-Lagrange框架下并分析虚拟流体状态合理的定义方式，将MGFM应用于处理无粘可压缩流体与板壳结构的非线性耦合。利用特有的界面状态预测方式，探讨耦合过程中的加速策略以提高计算效率。为避免界面处网格重构或变形带来额外的计算开销，本项目还将结合MGFM在定义虚拟流体区域和虚拟流体状态方面的特色，用规则的计算区域和简单的直角网格计算流场，数值模拟三维近体水下爆炸以及强射流和强冲击波对板壳结构冲击的动态过程。由于真实考虑到两种介质同时发生的非线性相互作用，该方法克服目前普遍采用的弱耦合技术在界面遭受强冲击或大变形时容易产生数值不稳定性的缺陷。

中文关键词： 修正的虚拟流体方法；流固耦合；虚拟流体状态；可压缩无粘流；板壳结构

英文摘要： The modified ghost fluid method (MGFM) developed recently, provides a new robust and efficient interface treatment for fluid-structure coupling, and has some successful applications. However, the problem of some special structure, such as plate or shell, remains to be resolved. By extending the latest technique of multi-medium Riemann problem in the Euler-Euler framework to the Euler-Lagrange framework and reasonably defining the ghost fluid status, this project will further develop the MGFM to treat the nonlinear coupling of inviscid compressible flow and plate/shell structure. According to the unique treatment for predicting the interfical status, this project will investigate the acceleration strategy of the coupling process to pursue higher efficiency. In order to avoid the additional computational cost induced by mesh regeneration or deformation in the vicinity of the interface, this project will also seek to simulate the flow field with the regular computational domain and Cartesian grid. This can be done due to the features of ghost fluid region and ghost fluid status in the MGFM. The dynamic processes of three-dimensional underwater explosion near plate/shell structures and strong jet or strong shock wave impacting on the plate/shell structure will be simulated numerically.Because the nonlinear fluid-str

英文关键词： Modified Ghost Fluid Method (MGFM)；Fluid-Structure Interaction (FSI)；Ghost Fluid State；Inviscid Compressible Flow；Plate/Shell Structure