Code Coupling via Jacobian-Free Newton-Krylov Algorithms with Application to Magnetized Fluid Plasma and Kinetic Neutral Models

Joseph, Ilon¹ 

[1] Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

关键词: COMPUTER CODES;    ALGORITHMS;    COUPLING;    DATA TRANSMISSION;    PLASMA;    MATRICES;    PLASMA FLUID EQUATIONS;    KINETIC EQUATIONS;   

DOI  :  10.2172/1249135
RP-ID  :  LLNL-TR--654916
PID  :  OSTI ID: 1249135
Others  :  TRN: US1601282

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来源: SciTech Connect

【 摘 要 】

Jacobian-free Newton-Krylov (JFNK) algorithms are a potentially powerful class of methods for solving the problem of coupling codes that address dfferent physics models. As communication capability between individual submodules varies, different choices of coupling algorithms are required. The more communication that is available, the more possible it becomes to exploit the simple sparsity pattern of the Jacobian, albeit of a large system. The less communication that is available, the more dense the Jacobian matrices become and new types of preconditioners must be sought to efficiently take large time steps. In general, methods that use constrained or reduced subsystems can offer a compromise in complexity. The specific problem of coupling a fluid plasma code to a kinetic neutrals code is discussed as an example.