skip to main content

SciTech ConnectSciTech Connect

Title: MILAGRO IMPLICIT MONTE CARLO: NEW CAPABILITIES AND RESULTS

Milagro is a stand-alone, radiation-only, code that performs nonlinear radiative transfer calculations using the Fleck and Cummings method of Implicit Monte Carlo (IMC). Milagro is an object-oriented, C++ code that utilizes classes in our group's (CCS-4) radiation transport library. Milagro and its underlying classes have been significantly upgraded since 1998, when results from Milagro were first presented. Most notably, the object-oriented design has been revised to allow for optimal stand-alone parallel efficiency and rapid integration of new classes. For example, the better design, coupled with stringent component testing, allowed for immediate integration of the full domain decomposition parallel scheme. (It is a simple philosophy: spend time on the design, and debug early and once.) Milagro's classes are templated on mesh type. Currently, it runs on an orthogonal, structured, not-necessarily-uniform, Cartesian mesh of up to three dimensions, an RZ-Wedge mesh, and soon a tetrahedral mesh. Milagro considers one-frequency, or ''grey,'' radiation with isotropic scattering, user-defined analytic opacities and equation-of-state, and various source types: surface, material, and radiation. Tallies produced by Milagro include energy and momentum deposition. In parallel, Milagro can run on a mesh that is fully replicated on all processors or on a mesh that is fully decomposed in themore » spatial domain. Milagro is reproducible, regardless of number of processors or parallel topology, and it now exactly conserves energy both globally and locally. Milagro has the capability for EnSight graphics and restarting. Finally, Milagro has been well verified with its use of Design-by-Contract{trademark}, component tests, and regression tests, and with its agreement to results of analytic test problems. By successfully running analytic and benchmark problems, Milagro serves to integrally verify all of its underlying classes, thus paving the way for other service packages based on these classes.« less
Authors:
;
Publication Date:
OSTI Identifier:
772826
Report Number(s):
LA-UR-00-6118
TRN: AH200121%%66
DOE Contract Number:
W-7405-ENG-36
Resource Type:
Conference
Resource Relation:
Conference: Conference title not supplied, Conference location not supplied, Conference dates not supplied; Other Information: PBD: 1 Dec 2000
Research Org:
Los Alamos National Lab., NM (US)
Sponsoring Org:
US Department of Energy (US)
Country of Publication:
United States
Language:
English
Subject:
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; BENCHMARKS; DEPOSITION; DESIGN; DIMENSIONS; EFFICIENCY; RADIATION TRANSPORT; RADIATIONS; SCATTERING; TESTING; TOPOLOGY