Many plant processes involve fluid flow combined with heat transfer. This can include phenomena such as phase change, condensation, two-phase fluid flow, critical flows, gas transport and more. Key large scale examples include nuclear plant integrated system transient and accident response, evaluation of containment and compartment conditions following pipe break events, water hammer evaluation and severe accident analysis. Smaller scale examples include characterizing localized phenomena such as tank and sump vortex behavior, suction strainer performance, thermal mixing in piping and transient thermal response of cables to over-current conditions, to name a few. FAI has a long history of thermal hydraulic testing and analysis.