采用高速摄像仪对两液柱撞击产生液膜的破裂过程进行了实验研究。分析了撞击液膜的破裂过程及表面波产生和传播过程，考察了射流直径、喷嘴间距和射流Weber数（We）对撞击液膜破裂的影响；定量分析了液膜表面波频率的变化及液膜破裂后的粒径分布情况。研究结果表明，液膜表面波传播频率随 We 的增大而增大，并沿液膜径向方向逐渐减小；随着射流We的增加，液膜边缘的液滴脱落频率增加；当We＞1000时，液膜表面产生大量液滴团，且液滴团对液膜破裂具有促进作用；液柱撞击液膜发生破裂后90%以上的量纲1液滴粒径分布在0～1之间。
The compositional distribution within aggregates of a given size is essential to the functionality of com- posite aggregates that are usually enlarged by rapid Brownian coagulation, There is no analytical solution for the process of such two-component systems, Monte Carlo method is an effective numerical approach for two-component coagulation, In this paper, the differentially weighted Monte Carlo method is used to investigate two-component Brownian coagulation, respectively, in the continuum regime, the free-molecular regime and the transition regime. It is found that （1） for Brownian coagulation in the continuum regime and in the free-molecular regime, the mono-variate compositional distribution, i.e., the number density distribution function of one component amount （in the form of volume of the component in aggregates） satisfies self-preserving form the same as particle size distribution in mono-component Brownian coagulation; （2） however, for Brownian coagulation in the transition regime the mono-variate compositional distribution cannot reach self-similarity; and （3） the bivariate compositional distribution, i.e., the combined number density distribution function of two component amounts in the three regimes satisfies a semi self-preserving form. Moreover, other new features inherent to aggregative mixing are also demonstrated; e.g., the degree of mixing between components, which is largely controlled by the initial compositional mass fraction, improves as aggregate size increases.
