One-dimensional drift-flux model for two-phase flow in pool rod bundle systems

► A new drift-flux correlation for pool rod bundle systems was developed. ► An experimental database was collected and benchmarked with the present model and existing models for rod bundles. ► The present model can predict 362 data points with a mean absolute error of 8.0%. ► A peak C0 (∼3.0) was found at 〈jg+〉≈0.5 in experimental data from pool rod bundle systems. ► Peak C0 conditions were explained by assuming a recirculation pattern in rod bundle systems.