Recently, iterative Quasi-Monte Carlo (iQMC) was introduced as a new method of neutron transport which combines deterministic iterative methods and quasi-Monte Carlo simulation for more efficient solutions to the neutron transport equation. Previous iQMC results utilized a uniform Cartesian grid with a piecewise-constant source. Similar to "teleportation error" in Implicit Monte Carlo (IMC) methods, the spatial discretization and piecewise-constant source can lead to a significant spatial error that limits convergence of the overall method. Taking concepts from IMC, we have developed a history-based discontinuous piecewise-linear source tilting scheme to reduce spatial error in iQMC. The source tilting method is described below and afterward we present results from a fixed-source 2D reactor-like problem adapted from the Takeda-1 Benchmark problem.
@article{arxiv.2306.14877,
title = {Reducing Spatial Discretization Error with Linear Discontinuous Source Tilting in Iterative Quasi-Monte Carlo for Neutron Transport},
author = {Samuel Pasmann and Ilham Variansyah and C. T. Kelley and Ryan G. McClarren},
journal= {arXiv preprint arXiv:2306.14877},
year = {2023}
}