Scaling of quench front and entrainment-related phenomena

The scaling of thermal hydraulic systems is of great importance in the development of experiments in laboratory-scale test facilities that are used to replicate the response of full-size prototypical designs. One particular process that is of interest in experimental modeling is the quench front that develops during the reflood phase in a pressurized water reactor (PWR) following a large-break loss of coolant accident (LOCA). The purpose of this study is to develop a scaling methodology such that the prototypical quench front related phenomena such as the entrainment of liquid droplets can be preserved in a laboratory-scale test facility which may have material, geometrical, fluid, and flow differences as compared to the prototypical case. A mass and energy balance on a Lagrangian quench front control volume along with temporal scaling methods are utilized in developing the quench front scaling groups for a phenomena-specific second-tier scaling analysis. A sample calculation is presented comparing the quench front scaling groups calculated for a prototypical Westinghouse 17 × 17 PWR fuel design and that of the geometry and material configuration used in the FLECHT-SEASET series of experiments.