Generating Variance Reduction Parameters for Shutdown Dose Rate Analysis of Moving Systems

摘要

The quantification of the shutdown dose rate (SDR) caused by photons emitted by activated structural materials is an important step of the design process of fusion energy systems (FES). FES are purposefully designed with modular components that can be moved in and out of the facility after shutdown for maintenance. It is particularly important to quantify the SDR during these operations that may cause facility personnel to be in closer proximity to activated equipment. SDR analysis requires both neutron and photon transport steps. typically performed by Monte Carlo (MC) calculations. The computational expense of obtaining highly accurate results in systems with heavy shielding, like FES. can be prohibitive. However, variance reduction (VR) methods can be used to increase the computational efficiency of these calculations.