Development and validation of models for bubble coalescence and breakup

New models were prosposed for bubble coalescence and breakup. They were implemented and validated for the case of air-water pipe flow in the Test Solver and CFX, respectively. The results were compared with the TOPFLOW L12 experimental data as well as the standard models in CFX. It was observed that good agreements with experimental data and substantial improvements in contrast to the standard models were achieved. In addition, the influence of bubble-induced turbulence models was studied. Large discrepancies show that modeling of bubble induced turbulence through additional source terms is still an open question.