反应结晶过程中产物粒子粒度分布的模拟——Ⅰ.混合特性的影响

SIMULATION OF CRYSTAL SIZE DISTRIBUTION IN REACTIVE-CRYSTALLIZATION(Ⅰ)THE EFFECTS OF MIXING

运用湍流理论及流体力学原理,分析了微观混合、湍流扩散、宏观返混的作用机理,并提出用两个无量纲准数来描述这三者之间的作用强弱,通过模型模拟,研究了它们对反应结晶过程中产物粒子的粒度分布的影响规律。结果发现:混合特性的影响具有多峰态特征。所得结果为过程优化提供了依据。

Based on turbulent theory,the mechanism of micromixing,turbulent dispersion and macromixing were interpreted.Two new dimensionless groups Mc and J_0 were presented in the first time to describe the relative acting level of them on the processes of chemical reaction and reactive- crystallization.The effects of mixing on crystal size distribution(CSD)were simulated by the mod- el which was established on the basis of the above mechanism.The results showed that the curve of the effects of mixing may possess both the peek and valley.The appearence of peek results from the relaxation of segregation state and that of valley results from the co-effects of micromixing and macromixing.