Matsuoka Yuki, Fukasawa Tomonori, Higashitani Ko, Yamamoto Ryoichi
Production Engineering Research Laboratory, Sumitomo Bakelite Co, Ltd, Shizuoka 426-0041, Japan.
Phys Rev E Stat Nonlin Soft Matter Phys. 2012 Nov;86(5 Pt 1):051403. doi: 10.1103/PhysRevE.86.051403. Epub 2012 Nov 14.
The rate of rapid Brownian coagulation is investigated for dispersions of spherical particles with particle volume fractions ranging from Øp = 0.003 to 0.1 by the direct numerical simulation method. This method explicitly considers hydrodynamic interactions (HIs) between particles by simultaneously solving for the motions of the dispersed particles and the host fluid. In the dilute limit, the rate of rapid Brownian coagulation decreases to approximately 0.3-0.5 times the theoretical Smoluchowski rate. We compare this result with results of previously reported experiments and theoretical predictions and find a strong correlation between them. This demonstrates that HIs between particles significantly reduce the coagulation rate. Moreover, the volume fraction dependence of the coagulation rate indicates that the coagulation rate increases with increasing volume fraction. At high particle volume fractions, the initial coagulation stage is affected by heterogeneous coagulation process before the steady state is reached.
通过直接数值模拟方法，研究了球形颗粒体积分数范围从Øp = 0.003至0.1的分散体的快速布朗凝聚速率。该方法通过同时求解分散颗粒和主体流体的运动，明确考虑了颗粒间的流体动力学相互作用（HIs）。在稀溶液极限下，快速布朗凝聚速率降至理论斯莫卢霍夫斯基速率的约0.3 - 0.5倍。我们将此结果与先前报道的实验结果和理论预测进行比较，发现它们之间存在很强的相关性。这表明颗粒间的流体动力学相互作用显著降低了凝聚速率。此外，凝聚速率对体积分数的依赖性表明，凝聚速率随体积分数的增加而增加。在高颗粒体积分数下，在达到稳态之前，初始凝聚阶段受非均相凝聚过程的影响。
