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针对高分散气雾两相流动体系,提出了一种新的传质理论表达式,其传质系数用Kolmogoroff长度时间尺度进行关联,并开发出基于MonteCarlo和CFD的联合模拟方案。运用该传质表达式和模拟方案,成功地模拟了氢氧化钠与二氧化碳的气雾两相射流中和反应体系。结果表明:相间传质时间尺度(1.6×10-4s)远小于弛豫时间尺度(4.5×10-4s),进一步研究说明尽管气雾相间传质的速率很快,但相间传递量是主要通过速度滑移实现的,相间传质对雾粒相的运动行为影响甚小,因而在工程上对于雾粒相运动行为的描述可以忽略传质的影响。由激光多普勒测速仪得到的实验数据证实了模拟结果,表明模拟能正确预测此类输运现象。
A new mass transfer theory is proposed for the highly dispersed aerosol two-phase flow system. The mass transfer coefficient is correlated with Kolmogoroff length time scale, and a joint simulation scheme based on Monte Carlo and CFD is developed. Using this mass transfer expression and simulation scheme, the gas-atom two-phase jet neutralization reaction system of sodium hydroxide and carbon dioxide has been successfully simulated. The results show that the time scale of mass transfer between phases (1.6 × 10-4s) is far less than the relaxation time scale (4.5 × 10-4s). Further studies indicate that although the mass transfer rate of aerosol is very fast, The effect of velocity slip and phase mass transfer has little effect on the movement behavior of fog phase. Therefore, the engineering description of fog phase motion behavior can neglect the effect of mass transfer. The experimental data obtained by laser Doppler velocimetry confirmed the simulation results, indicating that the simulation can correctly predict such transport phenomena.