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On the basis of Navier-Stockes equation and convection-diffusion equation, combined with surface ten-sion and penetration models, the equations of moment and mass transfer between bubble and the ambient non-Newtonian liquid were established. The formation of a single bubble from a submersed nozzle of 1.0 mm di-ameter and the mass transfer from an artificially fixed bubble into the ambient liquid were simulated by the volume- of-fluid (VOF) method. Good agreement between simulation results and experimental data confirmed the validity of the numerical method. Furthermore, the concentration distribution around rising bubbles in shear thinning non-Newtonian fluid was simulated. When the process of a single ellipsoidal bubble with the bubble deformation rate below 2.0 rises, the concentration distribution is a single-tail in the bubble’s wake, but it is fractal when the bubble deformation rate is greater than 2.0. For the overtaking of two in-line rising bubbles, the concentration dis-tribution area between two bubbles broadens gradually and then coalescence occurs. The bifurcation of concentra-tion distribution appears in the rear of the resultant bubble.
On the basis of Navier-Stockes equation and convection-diffusion equation, combined with surface ten-sion and penetration models, the equations of moment and mass transfer between bubble and the ambient non-Newtonian liquid were established. The formation of a single bubble from a submersed nozzle of 1.0 mm di-ameter and the mass transfer from an artificially fixed bubble into the ambient liquid were simulated by the volume-of-fluid (VOF) method. Good agreement between simulation results and experimental data confirmed the validity of the numerical when the process of a single ellipsoidal bubble with the bubble deformation rate below 2.0 rises, the concentration distribution is a single-tail in the bubble’s wake, but it is fractal when the bubble deformation rate is greater than 2.0. For the overtaking of two in-line rising bubbles, the concentration dis-tribu tion area between two bubbles broadens gradually and then coalescence occurs. The bifurcation of concentra-tion distribution appears in the rear of the resultant bubble.