COPPER LuREx: COMPARISON OF THE FRAGMENTATION OF COPPER- AND STEEL-CASED EXPLOSIVE DEVICES

Data from safety justification trials (SJTs) and calculations are used to predict the threats to the facility infrastructure from explosively-driven experiments. We aim to remove the requirement for future costly SJTs and rely solely on simulation, which necessitates validation and verification of our modelling methodology. To improve our fragment formation modelling and to test mitigation schemes, a range of simple steel-cased explosive devices have been designed and fielded in experiments. The devices were designed using leadingedge modelling techniques and gave us information regarding fragment formation and rotation. There were, however, some surprises in the results from these early trials. The LuREx (Lucille Radiographic Experiment) was a modified version of one of these devices which successfully allowed us to probe the early-time formation of fragments after crackformation has completed. Following on, a second device using a copper case (CLuREx) has been conducted to study fragmentation in a different, more ductile, metal.