Numerical investigation on effects of interphase force closures on liquid-phase turbulence and microbubbles distribution in vertical upward channel bubbly flow

Fully understanding mechanisms of the phase distribution and modulations of bubbles on the liquid-phase turbulence is very crucial for practical applications of bubbly flows. In this paper, influences of different interphase forces on both of them were widely investigated with an EulerLagrange model in a vertical upward channel bubbly flow laden with microbubbles. The flow field was simulated by using direct numerical simulations (DNS), while the bubble dynamics were fully analyzed by integration of Newtonian equations of motion taking into account of four different combinations of interphase forces. The phase distribution and turbulence statistics of the liquid phase were comprehensively analyzed for all testing cases. The results show that the local void fraction profiles for different testing cases are different, whereas profiles of the turbulent statistics for all cases have a similar distributing trend with different magnitudes. It can be concluded from the present results that the drag force, the lift force, and the added mass force have a comparatively important influence on the local void fraction profile and the liquid-phase turbulence. In contrast, the influence of the pressure gradient force seems to be extremely small. Copyright (c) 2011 Curtin University of Technology and John Wiley & Sons, Ltd.