Experimental and Computational Multiphase Flow

Article Title

Numerical investigation on the influencing interphase forces on bubble size distribution around NACA0015 hydrofoil


gas–liquid flow, bubble size distribution, hydrofoil, cavitation


Two-phase bubbly flows are prevalent in many industries and in nature. The aeration process that happens in the auto-venting turbine (AVT) is involved with two-phase bubbly flow downstream the turbine. The quality of the water in the turbine downstream is directly impacted by the bubble size distribution in the wake of turbine hydrofoils. In order to be able to accurately capture the physics associated with this process numerically, the interphase forces need to be considered carefully. Therefore, in this paper, the influence of interphase forces on the bubble size distribution around an NACA0015 hydrofoil is investigated. The numerical simulations require the consideration of the dynamic behaviors of two-phase flow and bubbles undergoing coalescence and breakup. For this purpose, the ensemble-averaged mass and momentum transport equations for continuous and dispersed phases are modeled within the two-fluid modelling framework. These equations are coupled with population balance equations (PBEs) to aptly account for the coalescence and breakup of the bubbles. The influence of the interphase forces: drag, lift, wall lubrication, virtual mass, turbulent dispersion forces, and turbulence transfer models, on the resulting bubble size distribution, is investigated and compared to existing experimental data.


Tsinghua University Press