PWR Facility Dose Modeling Using MCNP5 and the CADIS/ADVANTG Variance-Reduction Methodology

Preliminary Assessment of the Impact on Reactor Vessel dpa Rates Due to Installation of a Proposed Low Enriched Uranium (LEU) Core in the High Flux Isotope Reactor (HFIR)

“…The CADIS methodology implemented in ADVANTG works well for models containing multiple distributed sources and an arbitrary number of detector locations where the response at the different detectors can be reasonably expected to be similar. When the various expected detector responses may be significantly different (e.g., one location with a line-of-sight view of the core and one location where structural material such as a beam tube may obstruct the view of the core), or for global solutions in which many detector locations are near the core and many are far from the core [20], the ADVANTG code can implement an augmented version of the CADIS methodology with a technique known as Forward-Weighted CADIS (FW-CADIS). In this technique, the adjoint-biased source parameters for each detector location are multiplied by the inverse of the expected response at that location (i.e., they are divided by the forward flux at that location).…”

Characterization of Neutron and Gamma Beams at the TRIGA 2000 Reactor Beam Ports Using Monte Carlo

“…The first stage is the flux simulation and neutron-gamma spectrum on the reactor core using the MCNPX code. This MCNPX code was used because it has been tested for its ability in reactor criticality calculations supported by complete neutron interaction cross-sections data [7] [8]. To run the MCNPX code requires inputs; reactor geometry, reactor material composition, radiation source model, and tally flux.…”

Comparison of global variance reduction techniques for Monte Carlo radiation transport simulations of ITER

“…To date, this has typically been done using a discrete ordinates technique, such as in [2] where the Forward Weighted Consistent Adjoint Driven Importance Sampling (FW-CADIS) [3] method is used. There are also "rules of thumb" such as those of [4], or simply using analyst judgement to estimate cell weights or importances based on experience.…”