We have developed a new 3D multi-physics multi-material code, ALE-AMR, which combines Arbitrary Lagrangian Eulerian （ALE） hydrodynamics with Adaptive Mesh Refinement （AMR） to connect the continuum to the microstru...We have developed a new 3D multi-physics multi-material code, ALE-AMR, which combines Arbitrary Lagrangian Eulerian （ALE） hydrodynamics with Adaptive Mesh Refinement （AMR） to connect the continuum to the microstructural regimes. The code is unique in its ability to model hot radiating plasmas and cold fragmenting solids. New numerical techniques were developed for many of the physics packages to work efficiently on a dynamically moving and adapting mesh. We use interface reconstruction based on volume fractions of the material components within mixed zones and reconstruct interfaces as needed. This interface reconstruction model is also used for void coalescence and fragmentation. A flexible strength/failure framework allows for pluggable material models, which may require material history arrays to determine the level of accumulated damage or the evolving yield stress in J2 plasticity models. For some applications laser rays are propagating through a virtual composite mesh consisting of the finest resolution representation of the modeled space. A new 2nd order accurate diffusion solver has been implemented for the thermal conduction and radiation transport packages. One application area is the modeling of laser/target effects including debris/shrapnel generation. Other application areas include warm dense matter, EUV lithography, and material wall interactions for fusion devices.展开更多
While Eulerian smoothed particle hydrodynamics(SPH)method has received increasing attention in scientific and industrial communities owing to its high spatial accuracy,it exhibits excessive numerical dissipation due t...While Eulerian smoothed particle hydrodynamics(SPH)method has received increasing attention in scientific and industrial communities owing to its high spatial accuracy,it exhibits excessive numerical dissipation due to the fact that the flux is derived in particle pair pattern.In this paper,we adopt a one-dimensional weighted essentially non-oscillatory(WENO)reconstruction to reduce the numerical dissipation and improve the overall accuracy particularly in capturing the contact discontinuity.The underlying principle is to construct a 4-point stencil along the interacting line of each particle pair and then the WENO scheme is applied to reconstruct the initial states of the Riemann problem which determines the flow flux.A set of benchmark tests for both compressible and incompressible flows are studied to investigate the accuracy,robustness and versatility of the proposed Eulerian SPH method with the WENO reconstruction(ESPH-WENO).展开更多
基金the National Energy Research Scientific Computing Center,a DOE Office of Science User Facility supported by the Office of Science,U. S.Department of Energy under Contract No.DEAC02-05CH11231LBNL under DE-AC0205CH11231 was supported by the Director,Office of Science of the U.S.Department of Energy and the Petascale Initiative in Computational Science and Engineering+1 种基金LLNL was performed under the auspices of the U.S.Department of Energy by Lawrence Livermore National Security,LLC,Lawrence Livermore National Laboratory under Contract DE-AC5207NA27344UCLA and LLNL acknowledge UC Lab Fees Research Grant 09-LR-04-116741-BERA
文摘We have developed a new 3D multi-physics multi-material code, ALE-AMR, which combines Arbitrary Lagrangian Eulerian （ALE） hydrodynamics with Adaptive Mesh Refinement （AMR） to connect the continuum to the microstructural regimes. The code is unique in its ability to model hot radiating plasmas and cold fragmenting solids. New numerical techniques were developed for many of the physics packages to work efficiently on a dynamically moving and adapting mesh. We use interface reconstruction based on volume fractions of the material components within mixed zones and reconstruct interfaces as needed. This interface reconstruction model is also used for void coalescence and fragmentation. A flexible strength/failure framework allows for pluggable material models, which may require material history arrays to determine the level of accumulated damage or the evolving yield stress in J2 plasticity models. For some applications laser rays are propagating through a virtual composite mesh consisting of the finest resolution representation of the modeled space. A new 2nd order accurate diffusion solver has been implemented for the thermal conduction and radiation transport packages. One application area is the modeling of laser/target effects including debris/shrapnel generation. Other application areas include warm dense matter, EUV lithography, and material wall interactions for fusion devices.
基金This work was supported by the China Scholarship Council(Grant No.No.201906120035)Chi Zhang and Xiangyu Hu would like to express their gratitude to Deutsche Forschungsgemeinschaft(DFG)for their sponsorship(Grant No.DFG HU1527/12-4).
文摘While Eulerian smoothed particle hydrodynamics(SPH)method has received increasing attention in scientific and industrial communities owing to its high spatial accuracy,it exhibits excessive numerical dissipation due to the fact that the flux is derived in particle pair pattern.In this paper,we adopt a one-dimensional weighted essentially non-oscillatory(WENO)reconstruction to reduce the numerical dissipation and improve the overall accuracy particularly in capturing the contact discontinuity.The underlying principle is to construct a 4-point stencil along the interacting line of each particle pair and then the WENO scheme is applied to reconstruct the initial states of the Riemann problem which determines the flow flux.A set of benchmark tests for both compressible and incompressible flows are studied to investigate the accuracy,robustness and versatility of the proposed Eulerian SPH method with the WENO reconstruction(ESPH-WENO).
