Portable implementation of implicit methods for the UEDGE and

Technical Report · Wed Feb 17 04:00:00 EST 1999

OSTI ID:6266736

Rognlien, T D; Xu, X Q

A description is given of the parallelization algorithms and results for two codes used ex- tensively to model edge-plasmas in magnetic fusion energy devices. The codes are UEDGE, which calculates two-dimensional plasma and neutral gas profiles, and BOUT, which cal- culates three-dimensional plasma turbulence using experimental or UEDGE profiles. Both codes describe the plasma behavior using fluid equations. A domain decomposition model is used for parallelization by dividing the global spatial simulation region into a set of domains. This approach allows the used of two recently developed LLNL Newton-Krylov numerical solvers, PVODE and KINSOL. Results show an order of magnitude speed up in execution time for the plasma equations with UEDGE. A problem which is identified for UEDGE is the solution of the fluid gas equations on a highly anisotropic mesh. The speed up of BOUT is closer to two orders of magnitude, especially if one includes the initial improvement from switching to the fully implicit Newton-Krylov solver. The turbulent transport coefficients obtained from BOUT guide the use of anomalous transport models within UEDGE, with the eventual goal of a self-consistent coupling.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE Office of Defense Programs (DP)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6266736
• Report Number(s): UCRL-ID-133226; ON: DE00008018
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700000* -- Fusion Energy
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PARALLEL PROCESSING
PLASMA SIMULATION
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SIMULATION
U CODES