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Mark Sussman - One of the best experts on this subject based on the ideXlab platform.

  • Some improvements on Moment-of-Fluid Method in 3D rectangular hexahedrons
    arXiv: Computational Physics, 2020
    Co-Authors: Mark Sussman, Xizeng Zhao
    Abstract:

    The moment-of-Fluid Method (MOF) is an extension of the volume-of-Fluid Method with piecewise linear interface construction (VOF-PLIC). In MOF reconstruction, the optimized normal vector is determined from the reference centroid and the volume fraction by iteration. The state-of-art work by \citet{milcent_moment--Fluid_2020} proposed an analytic gradient of the objective function, which greatly reduces the computational cost. In this study, we further accelerate the MOF reconstruction algorithm by using Gauss-Newton iteration instead of Broyden-Fletcher-Goldfarb-Shanno (BFGS) iteration. We also propose an improved initial guess for MOF reconstruction, which improves the efficiency and the robustness of the MOF reconstruction algorithm. Our implementation of the code and test cases are available on our Github repository.

  • Incompressible multiphase flow and encapsulation simulations using the moment-of-Fluid Method
    International Journal for Numerical Methods in Fluids, 2015
    Co-Authors: Yongsheng Lian, Mark Sussman, Matthew Jemison, Yisen Guo, Trevor Helms, Marco Arienti
    Abstract:

    Summary A moment-of-Fluid Method is presented for computing solutions to incompressible multiphase flows in which the number of materials can be greater than two. In this work, the multimaterial moment-of-Fluid interface representation technique is applied to simulating surface tension effects at points where three materials meet. The advection terms are solved using a directionally split cell integrated semi-Lagrangian algorithm, and the projection Method is used to evaluate the pressure gradient force term. The underlying computational grid is a dynamic block-structured adaptive grid. The new Method is applied to multiphase problems illustrating contact-line dynamics, triple junctions, and encapsulation in order to demonstrate its capabilities. Examples are given in two-dimensional, three-dimensional axisymmetric (R–Z), and three-dimensional (X–Y–Z) coordinate systems. Copyright © 2015 John Wiley & Sons, Ltd.

  • Filament capturing with the Multimaterial Moment-of-Fluid Method
    Journal of Computational Physics, 2015
    Co-Authors: Matthew Jemison, Mark Sussman, Mikhail Shashkov
    Abstract:

    A novel Method for capturing two-dimensional, thin, under-resolved material configurations, known as "filaments," is presented in the context of interface reconstruction. This technique uses a partitioning procedure to detect disconnected regions of material in the advective preimage of a cell (indicative of a filament) and makes use of the existing functionality of the Multimaterial Moment-of-Fluid interface reconstruction Method to accurately capture the under-resolved feature, while exactly conserving volume. An algorithm for Adaptive Mesh Refinement in the presence of filaments is developed so that refinement is introduced only near the tips of filaments and where the Moment-of-Fluid reconstruction error is still large. Comparison to the standard Moment-of-Fluid Method is made. It is demonstrated that using filament capturing at a given resolution yields gains in accuracy comparable to introducing an additional level of mesh refinement at significantly lower cost.

  • a coupled level set moment of Fluid Method for incompressible two phase flows
    Journal of Scientific Computing, 2013
    Co-Authors: Matthew Jemison, Mark Sussman, Mikhail Shashkov, Marco Arienti, Eva Loch, Mitsuhiro Ohta, Yaohong Wang
    Abstract:

    A coupled level set and moment of Fluid Method (CLSMOF) is described for computing solutions to incompressible two-phase flows. The local piecewise linear interface reconstruction (the CLSMOF reconstruction) uses information from the level set function, volume of Fluid function, and reference centroid, in order to produce a slope and an intercept for the local reconstruction. The level set function is coupled to the volume-of-Fluid function and reference centroid by being maintained as the signed distance to the CLSMOF piecewise linear reconstructed interface. The nonlinear terms in the momentum equations are solved using the sharp interface approach recently developed by Raessi and Pitsch (Annual Research Brief, 2009). We have modified the algorithm of Raessi and Pitsch from a staggered grid Method to a collocated grid Method and we combine their treatment for the nonlinear terms with the variable density, collocated, pressure projection algorithm developed by Kwatra et al. (J. Comput. Phys. 228:4146---4161, 2009). A collocated grid Method makes it convenient for using block structured adaptive mesh refinement (AMR) grids. Many 2D and 3D numerical simulations of bubbles, jets, drops, and waves on a block structured adaptive grid are presented in order to demonstrate the capabilities of our new Method.

  • coupled level set volume of Fluid Method for simulation of injector atomization
    Journal of Propulsion and Power, 2013
    Co-Authors: Marco Arienti, Mark Sussman, Xiaoyi Li, Marios C Soteriou, C A Eckett, R J Jensen
    Abstract:

    This paper presents results of a multiphase computational Fluid dynamics code using a coupled level-set/volume-of-Fluid Method to simulate liquid atomization. This interface-capturing approach combines the mass conservation properties of the volume-of-Fluid Method with the accurate surface reconstruction properties of the level-set Method, and it includes surface tension as a volume force calculated with second-order accuracy. Developed by one of the authors, the multiphase code builds upon the combined level-set/volume-of-Fluid Methodology to enable bubbly flow, liquid breakup, and phase-change simulations. The extension presented in this paper couples a Lagrangian dispersed phase model for postbreakup tracking of droplets with block-structured adaptive mesh refinement on the Eulerian grid. Under an appropriate set of criteria, the transfer of droplets representation from the Eulerian to the Lagrangian discretization enables the simulation of sprays on larger domains and for longer physical times without...

T.-g. Liu - One of the best experts on this subject based on the ideXlab platform.

  • Modified Ghost Fluid Method for the Fluid Elastic-Perfectly Plastic Solid Interaction
    30th International Symposium on Shock Waves 2, 2017
    Co-Authors: S. Gao, T.-g. Liu
    Abstract:

    In this work, an exact Fluid elastic-perfectly plastic solid Riemann solver is proposed to define the ghost Fluid and ghost solid statuses. All the multi-material interactions are decoupled by the modified ghost Fluid Method (MGFM) in the Eulerian coordinate system. The Fluid is assumed to be compressible, while the solid is described as elastic-perfectly plastic material incorporating the von Mises yield condition. Multiple level set functions are employed to track the interfaces and distinguish respective material region. Numerical simulations of high-speed impact problems with two-dimensional Fluid-solid interfaces are presented.

  • The modified ghost Fluid Method for shock-structure interaction in the presence of cavitation
    Shock Waves, 2009
    Co-Authors: T.-g. Liu, Wen Fang Xie, C. Turangan, B. C. Khoo
    Abstract:

    In this work, the modified Ghost Fluid Method (MGFM) is applied to simulate compressible Fluid coupled to deformable structure in the presence of both shock and cavitation. Numerical results show that the MGFM for treatment of the Fluid-deformable structure coupling works efficiently in all pressure ranges and is capable of simulating both shock loading and cavitation reloading.

  • Numerical Simulation of Fluid-Structure Interaction Using Modified Ghost Fluid Method and Naviers Equations
    Journal of Scientific Computing, 2008
    Co-Authors: T.-g. Liu, B. C. Khoo, A. W. Chowdhury
    Abstract:

    In this work, we deal with the 1D compressible Fluid coupled with elastic solid in an Eulerian-Lagrangian system. To facilitate the analysis, the Naviers equation for elastic solid is cast into a 2×2 system similar to the Euler equation but in Lagrangian coordinate. The modified Ghost Fluid Method is employed to treat the Fluid-elastic solid coupling, where an Eulerian-Lagrangian Riemann problem is defined and a nonlinear characteristic from the Fluid and a Riemann invariant from the solid are used to predict and define the ghost Fluid states. Theoretical analysis shows that the present approach is accurate in the sense of approximating the solution of the Riemann problem at the interface. Numerical validation of this approach is also accomplished by extensive comparison to 1D problems (both water-solid and gas-solid) with their respective analytical solutions.

  • The modified ghost Fluid Method for coupling of Fluid and structure constituted with hydro-elasto-plastic equation of state
    SIAM Journal on Scientific Computing, 2007
    Co-Authors: T.-g. Liu, Wen Fang Xie, B. C. Khoo
    Abstract:

    In this work, the modified ghost Fluid Method (MGFM) [T. G. Liu, B. C. Khoo, and K. S. Yeo, J. Comput. Phys., 190 ( 2003), pp. 651-681] is further developed and applied to treat the compressible Fluid-compressible structure coupling. To facilitate theoretical analysis, the structure is modeled as elastic-plastic material with perfect plasticity and constituted with the hydro-elastoplastic equation of state [ H. S. Tang and F. Sotiropoulos, J. Comput. Phys., 151 ( 1999), pp. 790 815] under strong impact. This results in the coupled compressible Fluid-compressible structure system which is fully hyperbolic. To understand the effect of structure deformation on the interfacial and flow status, the compressible Fluid-compressible structure Riemann problem is analyzed in the consideration of material deformation with an approximate Riemann problem solver proposed to take into account the effect of material elastic-plastic deformation. We clearly show the ghost Fluid Method can be applied to treat the flow-deformable structure coupling under strong impact provided that a proper Riemann problem solver is used to predict the ghost Fluid states. And the resultant MGFM can work effectively and efficiently in such situations. Various examples are presented to validate and support the conclusions reached.

  • The accuracy of the modified ghost Fluid Method for gas--gas Riemann problem
    2006
    Co-Authors: T.-g. Liu, B. C. Khoo
    Abstract:

    Previous numerical tests have shown that the modified ghost Fluid Method (MGFM) [T.G. Liu, B.C. Khoo, K.S. Yeo, Ghost Fluid Method for strong shock impacting on material interface, J. Comput. Phys. 190 (2003) 651-681; T.G. Liu, B.C. Khoo, C.W. Wang, The ghost Fluid Method for compressible gas-water simulation, J. Comput. Phys. 204 (2005) 193-221] is robust and performs much better than the original GFM [R.P. Fedkiw, T. Aslam, B. Merriman, S. Osher, A non-oscillatory Eulerian approach to interfaces in multimaterial flows (the ghost Fluid Method), J. Comput. Phys. 152 (1999) 457-492]. In this work, a rigorous analysis is carried out on the accuracy of the MGFM when applied to the gas-gas Riemann problem. It is shown that at the material interface the MGFM solution approximates the exact solution to at least second-order accuracy in the sense of comparing to the exact solution of a Riemann problem. On the other hand, the results by the original GFM have generally no-order accuracy if the interface is not in normal motion.

Sussmanmark - One of the best experts on this subject based on the ideXlab platform.

B. C. Khoo - One of the best experts on this subject based on the ideXlab platform.

  • The Modified Ghost Fluid Method Applied to Fluid-Elastic Structure Interaction
    Advances in Applied Mathematics and Mechanics, 2011
    Co-Authors: Tiegang Liu, A. W. Chowdhury, B. C. Khoo
    Abstract:

    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.

  • The modified ghost Fluid Method for shock-structure interaction in the presence of cavitation
    Shock Waves, 2009
    Co-Authors: T.-g. Liu, Wen Fang Xie, C. Turangan, B. C. Khoo
    Abstract:

    In this work, the modified Ghost Fluid Method (MGFM) is applied to simulate compressible Fluid coupled to deformable structure in the presence of both shock and cavitation. Numerical results show that the MGFM for treatment of the Fluid-deformable structure coupling works efficiently in all pressure ranges and is capable of simulating both shock loading and cavitation reloading.

  • The modified ghost Fluid Method for coupling of Fluid and structure constituted with hydro-elasto-plastic equation of state
    SIAM Journal on Scientific Computing, 2007
    Co-Authors: T.-g. Liu, Wen Fang Xie, B. C. Khoo
    Abstract:

    In this work, the modified ghost Fluid Method (MGFM) [T. G. Liu, B. C. Khoo, and K. S. Yeo, J. Comput. Phys., 190 ( 2003), pp. 651-681] is further developed and applied to treat the compressible Fluid-compressible structure coupling. To facilitate theoretical analysis, the structure is modeled as elastic-plastic material with perfect plasticity and constituted with the hydro-elastoplastic equation of state [ H. S. Tang and F. Sotiropoulos, J. Comput. Phys., 151 ( 1999), pp. 790 815] under strong impact. This results in the coupled compressible Fluid-compressible structure system which is fully hyperbolic. To understand the effect of structure deformation on the interfacial and flow status, the compressible Fluid-compressible structure Riemann problem is analyzed in the consideration of material deformation with an approximate Riemann problem solver proposed to take into account the effect of material elastic-plastic deformation. We clearly show the ghost Fluid Method can be applied to treat the flow-deformable structure coupling under strong impact provided that a proper Riemann problem solver is used to predict the ghost Fluid states. And the resultant MGFM can work effectively and efficiently in such situations. Various examples are presented to validate and support the conclusions reached.

  • The accuracy of the modified ghost Fluid Method for gas--gas Riemann problem
    2006
    Co-Authors: T.-g. Liu, B. C. Khoo
    Abstract:

    Previous numerical tests have shown that the modified ghost Fluid Method (MGFM) [T.G. Liu, B.C. Khoo, K.S. Yeo, Ghost Fluid Method for strong shock impacting on material interface, J. Comput. Phys. 190 (2003) 651-681; T.G. Liu, B.C. Khoo, C.W. Wang, The ghost Fluid Method for compressible gas-water simulation, J. Comput. Phys. 204 (2005) 193-221] is robust and performs much better than the original GFM [R.P. Fedkiw, T. Aslam, B. Merriman, S. Osher, A non-oscillatory Eulerian approach to interfaces in multimaterial flows (the ghost Fluid Method), J. Comput. Phys. 152 (1999) 457-492]. In this work, a rigorous analysis is carried out on the accuracy of the MGFM when applied to the gas-gas Riemann problem. It is shown that at the material interface the MGFM solution approximates the exact solution to at least second-order accuracy in the sense of comparing to the exact solution of a Riemann problem. On the other hand, the results by the original GFM have generally no-order accuracy if the interface is not in normal motion.

  • GHOST Fluid Method APPLIED TO COMPRESSIBLE MULTI-PHASE FLOWS
    Modern Physics Letters B, 2005
    Co-Authors: T.-g. Liu, Wenfeng Xie, B. C. Khoo
    Abstract:

    In this work, we show that the Ghost Fluid Method (GFM) has actually zero-order accuracy if the gas-liquid interface is not in normal motion initially. The modified GFM (MGFM) is found to overcome this problem well. Examples are given to support the present analysis and conclusions obtained, and the MGFM is then applied to simulate compressible Fluid-structure interaction.

Frederic Risso - One of the best experts on this subject based on the ideXlab platform.

  • on the computation of viscous terms for incompressible two phase flows with level set ghost Fluid Method
    Journal of Computational Physics, 2015
    Co-Authors: Benjamin Lalanne, Lucia Rueda Villegas, Sebastien Tanguy, Frederic Risso
    Abstract:

    In this paper, we present a detailed analysis of the computation of the viscous terms for the simulation of incompressible two-phase flows in the framework of Level Set/Ghost Fluid Method when viscosity is discontinuous across the interface. Two pioneering papers on the topic, Kang et al. 10 and Sussman et al. 26, proposed two different approaches to deal with viscous terms. However, a definitive assessment of their respective efficiency is currently not available. In this paper, we demonstrate from theoretical arguments and confirm from numerical simulations that these two approaches are equivalent from a continuous point of view and we compare their accuracies in relevant test-cases. We also propose a new intermediate Method which uses the properties of the two previous Methods. This new Method enables a simple implementation for an implicit temporal discretization of the viscous terms. In addition, the efficiency of the Delta Function Method 24 is also assessed and compared to the three previous ones, which allow us to propose a general overview of the accuracy of all available Methods. The selected test-cases involve configurations wherein viscosity plays a major role and for which either theoretical results or experimental data are available as reference solutions: simulations of spherical rising bubbles, shape-oscillating bubbles and deformed rising bubbles at low Reynolds numbers.