2.5. Groupsets

Groupsets organize one or more energy groups into units that OpenSn solves together. Each groupset selects an angular quadrature and defines sweep aggregation, inner iteration, convergence, and optional diffusion-acceleration settings. When a problem contains multiple groupsets, their order also determines how OpenSn advances through the energy range during across-groupset iteration.

See the groupset user-guide reference for the available input fields and configuration examples. The iterative-methods reference explains how groupset settings affect solver behavior and convergence.

• 2.5.1. Multiple Groupsets in an Infinite-Medium