ADVANTG TUTORIAL: AUTOMATED VARIANCE REDUCTION FOR MCNP

摘要

This three-hour demonstration and tutorial will highlight the capabilities of ADVANTG for generating variance reduction parameters for fixed-source, continuous-energy Monte Carlo transport simulations using MCNP5. ADVANTG automates the process of generating 3-D space- and energy-dependent weight-window bounds and a consistent biased source distribution based on an approximate transport solution that is efficiently generated by the Denovo 3-D, parallel discrete ordinates package. The code implements the Consistent Adjoint Driven Importance Sampling (CADIS) method for accelerating individual tallies and the Forward-Weighted CADIS method for obtaining relatively uniform uncertainties across tallies in multiple regions and/or energy bins. The variance reduction parameters are generated in a format directly usable by unmodified versions of MCNP. ADVANTG can also be used as a front-end for Denovo and is capable of driving parallel SN calculations. The tutorial will cover the setup and execution of sample radiation detection and shielding problems. The open-source Visit 3-D visualization software will be used as an integral part of the tutorial. This tutorial will also include a brief summary of our experience applying ADVANTG to simulations of real-world problems, including several radiation detection systems and shielding analyses of the High Flux Isotope Reactor, Spallation Neutron Source, and ITER. ADVANTG will be available from RSICC starting in the first half of 2013. Licensed users are welcome to bring their laptops and follow along.