NUMERICAL AND EXPERIMENTAL-STUDY OF ON ACCIDENTAL DEPRESSURIZATION INAN ENCLOSURE CONTAINING HIGH-PRESSURE LIQUID

A mixture model is developed for the simulation of a transient two-pha se-flow induced by the accidental depressurization of an enclosure con taining initially high-pressure liquid It is based on a three-equation system and a drift-flux model for describing the relative phase motio n. The unsteady solution is obtained by means of a fully implicit sche me. An original treatment of the drift-flux term (based on the donor c ell concept) in the energy equation is used. The comparison between th e numerical results and those given by experiments for two accidental events is quite good. This fast-running approach (in terms of CPU time ) allows real-time simulations, which are of primary importance for co ntrol system modeling and simulator design.