Ji Bingqiang, Singh Amrit, Feng Jie
Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Nano Lett. 2022 Jul 13;22(13):5626-5634. doi: 10.1021/acs.nanolett.2c01102. Epub 2022 Jun 4.
Bubbles dispersed in liquids are widely present in many natural and industrial processes and play a key role in mediating mass transfer during their lifetime from formation to rising to bursting. In particular, nano/microsized particulates and organisms present in the bulk water can be highly enriched in the jet drops ejected during bubble bursting, impacting global climate and public health. However, the detailed mechanism of this enrichment remains obscure with the enrichment factor being difficult to predict. Here, we experimentally investigate the enrichment of nano/microsized particles in bubble bursting jet drops and highlight the underlying hydrodynamic mechanism, combining the effects of bubble scavenge and bursting on the transport of particles. Scaling laws for the enrichment factor are subsequently proposed that describe both our and prior experimental results reasonably well. Our study may provide new insights for water-to-air transfer of bulk particulates such as microbes related to bubble bursting.
分散在液体中的气泡广泛存在于许多自然和工业过程中，并且在其从形成到上升再到破裂的整个生命周期内，在介导传质过程中发挥着关键作用。特别是，大量水体中存在的纳米/微米级颗粒和生物体在气泡破裂时喷射出的射流液滴中会高度富集，从而影响全球气候和公众健康。然而，这种富集的详细机制仍然不清楚，富集因子也难以预测。在此，我们通过实验研究了气泡破裂射流液滴中纳米/微米级颗粒的富集情况，并结合气泡清除和破裂对颗粒传输的影响，突出了潜在的流体动力学机制。随后提出了富集因子的标度律，该标度律能够较好地描述我们的实验结果以及先前的实验结果。我们的研究可能为与气泡破裂相关的诸如微生物等大量颗粒从水到空气的转移提供新的见解。
