AVANCES EN SIMULACIÓN CFD DE FLASHING PARA ANÁLISIS DE SEGURIDAD NUCLEAR CON OPENFOAM

DARIO M. GODINO; SANTIAGO F. CORZO; DAMIAN E. RAMAJO

Concordia-Argentina y Salto-Uruguay

Congreso; MECOM 2023 - Congreso Argentino de Mecánica Computacional; 2023

Universidad Tecnológica Nacional - Facultad Regional Concordia. Universidad de la República de Uruguay

In nuclear safety analysis, the phenomenon of flashing is particularly relevant due to its importance in events such as the Loss of Coolant accident. In this regard, flasing has been thoroughly studied through experiments and system code simulations, but three-dimensional Computational Fluid Dynamics (CFD) is still premature. In this work, the Eulerian two-fluid model was used in the OpenFOAM environment to solve four experimental flashing tests. The solver was customized, focusing on the interfacial transfer terms and specially on the heat transfer parameters, such as the bubble diameter. The thermophisical properties for water ansd steam were represented through Polynomials, IAPWS-IF97 tables and also the ideal gas model for steam. Using the available experimental data, the results were evaluated, and the limitations were discussed, concluding that the developed computational model is suitable for simulating fast depressurization problems. The mayor discrepances were for the void fraction estimation at the begining of the events, while the pressure and temperature drops were good approached.