RELAP5

A thermal-hydraulic simulation code used in nuclear safety analysis for modelling reactor coolant system transients. Referenced in the report series as the target for simulator-coupling at Level 4 of the capability-gradient.

The projection agent role in Pattern 9 architectures couples to RELAP5 (or similar codes) for Level 3 SA: computing forward projections of plant state based on current conditions. The LLM specifies boundary conditions and interprets results; the physics comes from the simulation code, not from the LLM.