OpenFOAM CFD simulation of critical heat flux in vertical pipe under typically PWR conditions

Abstract

This paper aims to see how well the open-source CFD code OpenFOAM can simulate the critical heat flux (CHF) in vertical pipe under extreme conditions, close to PWR operating conditions. The two-fluid approach combined with an extended wall boiling model was used to forecast CHF. The 2006 CHF look-up table was employed as benchmark data. The wall temperature jump was used as the criterion for predicting departure from nucleate boiling (DNB) type CHF. Good agreement was obtained between CHF from look-up table and calculated values. The effects of pressures, mass flow rates, and equilibrium qualities on CHF are investigated. CHF location and maximum volume fraction at corresponding CHF were also obtained. Most of the deviations are within 15% of error. The average absolute error of the simulated CHF was 7%. The findings indicate that OpenFOAM promises to forecast boiling flow and CHF in the PWR reactor fuel assembly geometry.