Numerical analysis of turbulence structures induced by bubble buoyancy

Abstract

Turbulence structure in rising bubbly flow driven by bubble buoyancy was analyzed by using the Eulerian-Lagrangian equation model. A new calculation method for two-way interaction between dispersed bubble and liquid phase was proposed to simulate accurately the local fluctuation of liquid flow induced by bubble migration. The present two-dimensional simulation revealed that, (1) the turbulence structure had the longer wave length in vertical direction in case of the larger bubble, (2 ) the wave spectrum of kinetic energy of the liquid phase depended sensitively on the average void fraction and the lift force of bubble.