Random walk procedure for improving the computational efficiency of the implicit Monte Carlo method for nonlinear radiation transport

Journal Article · Fri Jun 01 00:00:00 EDT 1984 · J. Comput. Phys.; (United States)

DOI:https://doi.org/10.1016/0021-9991(84)90130-X· OSTI ID:7095108

Fleck, Jr, J A; Canfield, E H

An unconditionally stable Monte Carlo method for solving the frequency dependent equations of nonlinear radiation transport has been described previously. One of the central features of this method is the replacement of a portion of the absorption and reemission of radiation by a scattering process. While the inclusion of this scattering process assures the accuracy and stability of solutions regardless of local opacity values, it becomes time consuming when the local opacity is large. A procedure is derived for replacing a large number of local scattering events by a single advance of the coordinates and time of a particle. This procedure, developed by appealing to the theory of random flights, is integrated into the implicit Monte Carlo scheme and is invoked only when certain conditions are met. Numerical tests indicate that the random walk procedure can substantially improve the computational efficiency of the implicit Monte Carlo method without affecting its accuracy. This random walk procedure with suitable modifications should be applicable to the Monte Carlo solution of other transport problems involving large amounts of scattering.

• Research Organization: University of California, Lawrence Livermore National Laboratory, Livermore, California 94550
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7095108
• Journal Information: J. Comput. Phys.; (United States), Vol. 54:3
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
MONTE CARLO METHOD
EFFICIENCY
RADIATION TRANSPORT
ABSORPTION
BLACKBODY RADIATION
NONLINEAR PROBLEMS
NUMERICAL SOLUTION
RANDOMNESS
SCATTERING
ELECTROMAGNETIC RADIATION
RADIATIONS
654001* - Radiation & Shielding Physics- Radiation Physics
Shielding Calculations & Experiments