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Simulations of Compressible Two-Medium Flow by Runge-Kutta Discontinuous Galerkin methods with the ghost fluid method

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Communications in Computational Physics 2008年第2期3卷 479-504页

作者： Jianxian Qiu Tiegang Liu Boo Cheong Khoo Department of Mathematics Nanjing UniversityNanjingJiangsu 210093China Institute of High Performance Computing ♯01−01 The CapricornSingapore Science Park IISingapore 117528Singapore Department of Mathematics Beijing University of Aeronautics and AstronauticsBeijingChina Department of Mechanical Engineering National University of SingaporeSingapore 119260Singapore./Singapore-MIT Alliance4 Engineering Drive 3National University of SingaporeSingapore 117576Singapore.

The original ghost fluid method (GFM) developed in [13] and the modifiedGFM (MGFM) in [26] have provided a simple and yet flexible way to treat twomediumflow problems. The original GFM and MGFM make the material interface"invisible" during computations and the calculations are carried out as for a singlemedium such that its extension to multi-dimensions becomes fairly straightforward.The Runge-Kutta discontinuous Galerkin (RKDG) method for solving hyperbolic conservationlaws is a high order accurate finite element method employing the usefulfeatures from high resolution finite volume schemes, such as the exact or approximateRiemann solvers, TVD Runge-Kutta time discretizations, and limiters. In this paper,we investigate using RKDG finite element methods for two-medium flow simulationsin one and two dimensions in which the moving material interfaces is treated via nonconservativemethods based on the original GFM and MGFM. Numerical results forboth gas-gas and gas-water flows are provided to show the characteristic behaviors ofthese combinations.

关键词： Runge-Kutta discontinuous Galerkin method WENO scheme ghost fluid method approximate Riemann problem solver.

The Modified ghost fluid method Applied to fluid-Elastic Structure Interaction

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Advances in Applied Mathematics and Mechanics 2011年第5期3卷 611-632页

作者： Tiegang Liu A.W.Chowdhury Boo Cheong Khoo LMIB and School of Mathematics and Systems Science Beijing University of Aeronautics and AstronauticsBeijing 100191China Department of Mechanical Engineering National University of SingaporeSingapore 119260Singapore Singapore-MIT Alliance 4 Engineering Drive 3National University of SingaporeSingapore 117576Singapore

In this work,the modified ghost fluid method is developed to deal with 2D compressible fluid interacting with elastic solid in an Euler-Lagrange coupled system.In applying the modified ghost fluid method to treat the fluid-elastic solid coupling,the Navier equations for elastic solid are cast into a system similar to the Euler equations but in Lagrangian coordinates.Furthermore,to take into account the influence of material deformation and nonlinear wave interaction at the interface,an Euler-Lagrange Riemann problem is constructed and solved approximately along the normal direction of the interface to predict the interfacial status and then define the ghost fluid and ghost solid states.Numerical tests are presented to verify the resultant method.

关键词： fluid-elastic structure interaction Euler-Lagrange coupling Euler-Lagrange Riemann problem ghost fluid method modified ghost fluid method

A ghost fluid BASED FRONT TRACKING method FOR MULTIMEDIUM COMPRESSIBLE FLOWS

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Acta Mathematica Scientia 2009年第6期29卷 1629-1646页

作者：王东红赵宁胡偶刘剑明 College of Science Nanjing University of Aeronautics and Astronautics College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

Recent years the modify ghost fluid method （MGFM） and the real ghost fluid method （RGFM） based on Riemann problem have been developed for multimedium compressible flows. According to authors, these methods have only been used with the level set technique to track the interface. In this paper, we combine the MCFM and the RGFM respectively with front tracking method, for which the fluid interfaces are explicitly tracked by connected points. The method is tested with some one-dimensional problems, and its applicability is also studied. Furthermore, in order to capture the interface more accurately, especially for strong shock impacting on interface, a shock monitor is proposed to determine the initial states of the Riemann problem. The present method is applied to various one- dimensional problems involving strong shock-interface interaction. An extension of the present method to two dimension is also introduced and preliminary results are given.

关键词： front tracking method ghost fluid method multimedium compressible flow Riemann problem

A three-dimensional Eulerian method for the numerical simulation of high-velocity impact problems

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Chinese Physics B 2014年第3期23卷 338-347页

作者：吴士玉刘凯欣陈千一 LTCS and Department of Mechanics and Engineering Science College of Engineering Peking University Center for Applied Physics and Technology Peking University

In the present paper, a three-dimensional （3D） Eulerian technique for the 3D numerical simulation of high-velocity impact problems is proposed. In the Eulerian framework, a complete 3D conservation element and solution element scheme for conservative hyperbolic governing equations with source terms is given. A modified ghost fluid method is proposed for the treatment of the boundary conditions. Numerical simulations of the Taylor bar problem and the ricochet phenomenon of a sphere impacting a plate target at an angle of 60~ are carried out. The numerical results are in good agreement with the corresponding experimental observations. It is proved that our computational technique is feasible for analyzing 3D high-velocity impact problems.

关键词： three-dimensional numerical simulation conservation element and solution element （CE/SE）method ghost fluid method high-velocity impact

A sharp interface approach for cavitation modeling using volume-of-fluid and ghost-fluid methods

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Journal of Hydrodynamics 2017年第6期29卷 917-925页

作者： Thad Michael Jianming Yang Frederick Stern NSWC Carderock Division 9500 MaeArthur Blvd.West BethesdaMD 20817USA Fidesi Solutions LLC PO Box 734Iowa CityIA 52244USA IIHR-Hydroscience and Engineering University of lowaIowa CityIA 52242USA

This paper describes a novel sharp interface approach for modeling the cavitation phenomena in incompressible viscous flows. A one-field formulation is adopted for the vapor-liquid two-phase flow and the interface is tracked using a volume of fluid（VOF） method. Phase change at the interface is modeled using a simplification of the Rayleigh-Plesset equation. Interface jump conditions in velocity and pressure field are treated using a level set based ghost fluid method. The level set function is constructed from the volume fraction function. A marching cubes method is used to compute the interface area at the interface grid cells. A parallel fast marching method is employed to propagate interface information into the field. A description of the equations and numerical methods is presented. Results for a cavitating hydrofoil are compared with experimental data.

关键词： Incompressible flow two-phase flow cavitation modeling sharp interface method ghost fluid method volume of fluidmethod level set method parallel fast marching method marching cubes method

Numerical Simulation for a Droplet Fission Process of Electrowetting on Dielectric Device

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Communications in Computational Physics 2010年第5期7卷 1076-1094页

作者： Dongdong He Huaxiong Huang Yongji Tan School of Mathematical Sciences Fudan UniversityShanghaiChina Department of Mathematics and Statistics York UniversityTorontoCanada

Electrowetting has been proposed as a technique for manipulating dropletssurrounded by air or oil. In this paper, we discuss the modeling and simulation of thedroplet fission process between two parallel plates inside an electrowetting on dielectric (EWOD) device. Since the gap between the plates is small, we use the two-phaseHele-Shaw flow as a model. While there are several high order methods around, suchas the immersed interface methods [1, 2], we decide to use two first-order methods forsimplicity. A ghost-fluid (GF) method is employed to solve the governing equationsand a local level set method is used to track the drop interface. For comparison purposes, the same set of two-phase Hele-Shaw equations are also solved directly usingthe immersed boundary (IB) method. Numerical results are consistent with experimental observations reported in the literature.

关键词： Electrowetting ghost fluid method Hele-Shaw equations immersed boundary method local level set method microfluidics moving interface two-phase flow

多介质流体力学Euler-Lagrange耦合计算的GEL方法研究

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多介质流体力学Euler-Lagrange耦合计算的GEL方法研究

作者：姚阳中国工程物理研究院

学位级别：硕士

在多介质流体动力学数值模拟计算方法中，Euler和Lagrange方法都有各自的优越性和局限性，如何有效利用它们的优势是多介质流体力学数值模拟计算的重要研究方向之一。本文基于幻影流体方法（ghost fluid method）和Level Set函数，开展... 详细信息

在多介质流体动力学数值模拟计算方法中，Euler和Lagrange方法都有各自的优越性和局限性，如何有效利用它们的优势是多介质流体力学数值模拟计算的重要研究方向之一。本文基于幻影流体方法（ghost fluid method）和Level Set函数，开展了Euler-Lagrange耦合的GEL（ghost-fluid Euler-Lagrange）数值计算方法的研究，初步建立了GEL的二维多介质流体动力学程序。本文主要研究内容包括： 1)开展了ghost fluid method多介质流体力学计算方法研究。 2)详细阐述了GEL方法的基本理论，在以SCB格式编制的二维多介质流体力学Euler计算程序和二维弹塑性流有限元计算程序的基础上，建立了耦合Euler-Lagrange计算的二维GEL程序。在GEL耦合方法和本文耦合程序的基础上，给出了连接其他标准Euler和Lagrange计算程序的流程图。 3)采用GEL程序对一维黎曼问题（Riemann problem）和二维移动边界问题（cylinderlift-off problem）进行了数值模拟计算，一维计算结果与高精度PPM方法计算结果吻合，二维计算结果与文献给出的结果一致，初步验证了耦合Euler-Lagrange计算方法和计算程序的正确性。尽管本文的方法目前仅在对一维和二维适用，但耦合方法本身可以推广到三维。

关键词： Euler-Lagrange耦合 GEL方法 ghost fluid method 内边界条件

Euler-Lagrange耦合计算的GEL方法

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Euler-Lagrange耦合计算的GEL方法