喷射反应器内液-液湍流微观混合的研究

通过定义局部分离度,来定量表征喷射器内液-液湍流微观混合规律。其定义式为:(实验所得H~+浓度-模拟所得H~+浓度)/模拟所得H~+浓度。选用酸碱反应体系,利用PLIF技术得到沿喷射器轴线的H~+浓度;采用Fluent软件,利用Standard k-ε模型,模拟获得相同操作条件下的H~+浓度变化趋势。得到不同操作条件下,分离度沿喷射器轴线的变化,结果表明:(1)引流速度不变,喷嘴速度越大,两流体越容易达到微观尺度的均匀混合;(2)喷嘴速度不变,引流速度越大,两流体反而不容易达到微观尺度上的均匀混合;(3)速度比一定的情况下,喷嘴速度越大,越有利于流体的微观混合。

Research on turbulent micro-mixing in a jet reactor

Local separating degree was defined to quantificationally characterise liquid-liquid turbulent micro-mixing in a jet reactor,which was defined as:(the experimental H~+ concentration-the simulative H~+ concentration)/ the simulative H~+ concentration.Acid-base reaction was selected to study micro-mixing character.H~+ concentration along the axis of jet reactor was got by the means of PLIF;Using Fluent,H~+ concentration under the same operational conditions was obtained through standardκ-ε.The change of separating degree along the axis of jet reactor under different operational conditions was received.The result shows:(1)With constant suction flow speed,the bigger the ejection flow speed is,the easier it is to be uniform at micro-scale.(2)With constant ejection flow speed,the bigger the suction flow speed is,the more hard it is to be uniform at micro-scale.(3) With constant speed ratio,the bigger the ejection flow speed,the easier it is to be uniform at micro-scale.