Instrumentation development for low range, long line differential pressure measurements

A major experimental facility planned for the investigation of the reflood and refill phases of a loss-of-coolant accident in a pressurized water reactor (PWR) is a full-scale model of a PWR upper plenum, designated as the Upper Plenum Test Facility (UPTF). One of the goals of the test program is to determine the characteristics of the dynamic steam-water flow at the core/upper plenum interface. To meet this need, an instrumentation system designed to measure small differential pressure generated by this two-phase flow has been developed, fabricated, and evaluated.