Numerical Simulation of Subcooled Flow Boiling in Water and NaCl Solution Using a Coalescence Breakup Nucleation Model

This study systematically investigates vapor bubble dynamics in subcooled flow boiling systems for both aqueous and saline solutions across a comprehensive range of thermal-hydraulic conditions. Through Eulerian multiphase computational simulations, we rigorously evaluate the predictive capabilities of various bubble interaction models including coalescence, breakage, and nucleation mechanisms. The numerical predictions are quantitatively validated against experimental benchmark data with detailed error analysis performed. Key findings demonstrate that simulation accuracy is critically dependent on the optimal selection and combination of bubble interaction models. Specifically, the Yao correlation for bubble nucleation yields superior predictive performance compared with alternative approaches. Notably, the exclusion of coalescence models in saline solution simulations enhances the accuracy, attributable to ionic interference effects on bubble interactions. Furthermore, sensitivity analysis reveals that bubble breakage phenomena exert minimal influence on simulation outcomes under most operational conditions.