熱・物質輸送をともなう蒸気/ガス気泡の膨張・収縮運動 : 流体工学,流体機械

抄録

The radial motion of a spherical vapor/gas bubble in acoustic fields is investigated numerically. A mathematical model is derived with an assumption of the spatial uniformity of pressure in the bubble. The model includes the effect of spatial distribution of temperature and concentration, and heat and mass transfer at the bubble wall. The small-amplitude bubble oscillation in a hydrothermal system is simulated. The numerical results show that the spatial uniformity of pressure is valid. The amplitude of radial motion is correlated well with the nondimensional interdiffusion coefficient D_gv/ωR₀² where D_gv denotes the interdiffusion coeficient, ω the driving frequency, and R₀ the initial bubble radius. The phase change and gas diffusion at the bubble wall interact to each other. The interaction enhances the mass transfer at the bubble wall.