实验测定了低气速下CO2气泡群在牛顿流体、剪切变稀流体及黏弹性流体中的气含率。讨论了流体的流变性、质量分数及表观气速对气含率的影响。结果表明:在3种不同性质的流体中,气含率均随表观气速的增大而增大。同时发现流体性质对气含率具有不同的影响:对于牛顿流体,表观气速较低时,质量分数对气含率影响可忽略;对于非牛顿流体,气含率随着流动指数n的减小而减小,即剪切变稀效应对气含率有负作用,而黏弹性对气含率的影响可忽略。气含率是气液传质过程设计中最重要的参数,因此研究结果为进一步研究CO2气泡群在非牛顿流体中的传质奠定了一定基础。
The gas holdups of CO2 bubble swarm at low superficial gas velocity in Newtonian fluid,shear thinned fluid and viscoelastic fluid were measured.The influences of rheological property,mass fraction and superficial gas velocity on the gas holdup were investigated.The results show that the gas holdups in three fluids all increase with the increase of superficial gas velocity,and different fluid has different effects on the gas holdup.The effect of mass fraction on the gas holdup in Newtonian fluid at low superficial gas velocity is negligible.For non-Newtonian fluid,the gas holdup decreases with the decrease of flow index n,that is,shear thinning effect has negative impact on the gas holdup,and the influence of viscoelasticity on the gas holdup is negligible.The gas holdup is the most important parameter for the gas-liquid mass transfer process design,and it provides a solid foundation for the research on mass transfer of CO2 bubble swarm in non-Newtonian fluid.