A New Experimental Facility for an Imrpoved Understanding of CHF in a CANDU Moderator Duing Severe Accidents

Abstract

The critical heat flux has been studied extensively, however gaps in knowledge still exist and persist. The design methodology and experimental techniques to be used in a new experimental facility are discussed. These include experimental measurements of the CHF for a variety of geometries in addition to measurements of the mechanisms triggering CHF for conditions similar to those expected for the moderator of a CANDU reactor during severe accidents. These techniques include Electrical Resistance Tomography (ERT) to measure local void fractions in addition to high-speed imaging using a Particle Image Velocimetry (PIV) system.