The Euler–Euler two fluid approach has been widely adopted in computational multi-fluid dynamic (CMFD) simulation of nucleate boiling flow. Accurate prediction of bubble size and interphase forces are desired to properly model interphase momentum transfer in the CMFD simulation. Bubble dynamics, including nucleation, coalescence/breakup and condensation, should be modeled to calculate bubble size variation. In the meantime, modeling of interphase forces is crucial to predict distribution of void fraction. Numerous closure models have been developed for bubble dynamics and interphase forces. Diverse model combinations were reported depending on the specific application. As a step forward to converge the diversity, efforts are dedicated to establish a methodology to iteratively screen the closure models for nucleate flow boiling at elevated pressures based on the DEBORA experiment. In the proposed methodology, the closure models for each physics are first evaluated and sorted based on the predicted value in fixed-point analysis and its effect on CMFD results observed in separate-effect analysis. The second part of the methodology is iterative screening. To achieve accurate bubble size prediction, the optimal coalescence model is identified for each breakup model. With the optimal coalescence counterpart, the optimal breakup model is then identified. For the interphase force models, the optimal lift force model is first determined based on the CMFD simulation with the same drag force model and without wall lubrication force model. The optimal wall lubrication force and drag force model are selected in sequence. Utilized one single case of DEBORA experiments, the optimal set of the coalescence/breakup models, i.e., Prince et al.’s and Luo et al.’s models, and the interphase models, i.e., Tomiyama et al.’s models for drag and lift force, Lubchenko et al.’s model for wall lubrication force and Burns et al.’s model for turbulence dispersion force has been selected. Validation of the model combination based on more DEBORA experiment datasets and Bartolomei et al.’s experiment shows promising prediction accuracy.
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