International Journal of Multiphase Flow, Vol.54, 31-42, 2013
Modeling of bubble coalescence and break-up considering turbulent suppression phenomena in bubbly two-phase flow
New mechanistic bubble coalescence and break-up models considering turbulent suppression phenomena, which can possibly occur in the high liquid velocity condition of turbulent bubbly two-phase flow, are presented. The energy exchange mechanism between a turbulent eddy and interfacial structure was taken into account in the efficiency terms. Numerical simulations of turbulent bubbly flow were conducted in a CFD code to evaluate the newly developed models, in comparison with other advanced models coupled with a bubble-induced turbulent effect for one-group interfacial area transport equation. Local measurements of the bubble characteristics on the bubble size evolution along a vertical pipe flow were performed at KAERI-VAWL test facility using the five-sensor conductivity probe method to provide database for models validation. Results from the calculation clearly show the improvements of the newly developed models. (C) 2013 Elsevier Ltd. All rights reserved.
Keywords:Interfacial area concentration;Coalescence;Break-up;Turbulent suppression phenomena;Turbulent eddy size;CFD