Automatic Variance Reduction for Three-Dimensional Monte Carlo Simulations by the Local Importance Function Transform—II: Numerical Results

The performance of the local importance function transform (LIFT) method for several three-dimensional, linearly anisotropic-scattering, one-group, and multigroup transport problems is demonstrated. In these problems, the LIFT method is shown to be more efficient than the AVATAR scheme, which is one of the most efficient variance reduction techniques currently available in a production Monte Carlo code. For most of the problems considered, the LIFT method produces higher figures of merit than AVATAR, even when the LIFT method is used as a black box.