Critical Assemblies: Dragon Burst Assembly and Solution Assemblies

TL;DR

This paper reviews historical critical assembly experiments at Los Alamos, develops models for simulation of criticality excursions using coupled neutronic-hydrodynamic methods, and validates results against historic data.

Contribution

It introduces a new modeling methodology for critical assemblies that integrates neutronic and hydrodynamic simulations for dynamic criticality analysis.

Findings

Simulation results align well with historic data

Models enable multi-physics criticality excursion studies

Utilizes MCNP for nuclear kinetic parameter calculations

Abstract

This work reviewed the historical literature associated with the Dragon experiment and Water Boiler reactors operated at Los Alamos during the Manhattan Project. Frisch's invited talk given at the Fast Burst Reactor Conference held the University of New Mexico in Albuquerque, NM in 1969 is quoted. From the literature review, basic models for the Dragon experiment and for a Water Boiler type assembly (aqueous homogeneous reactor) were created that can be used for conducting multi-physics simulations for criticality excursion studies. This methodology utilizes the coupled neutronic-hydrodynamic method to perform a time-dependent dynamic simulation of a criticality excursion. MCNP was utilized to calculate important nuclear kinetic parameters that were incorporated into the models. Simulation results compared reasonably well with historic data.