arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1911.03301physics.flu-dyn
收藏

粘性液滴撞击低粘性液池时的两股射流

Two jets during the impact of viscous droplets onto a less-viscous liquid pool

Quan Ding, Tianyou Wang, Zhizhao Che

摘要:

通常认为,当液滴撞击到液体池上时,会发生沃辛顿射流。然而,在这个实验研究的影响粘性液滴上的粘性较低的液体池,我们确定另一个射流除了沃辛顿射流,形成一个双射流现象。在一次撞击事件中,两股喷流,一股表面爬升喷流和一股沃辛顿喷流,可能相继出现。通过仔细调整的影响条件,我们发现,两个射流现象是共同控制的液滴池粘度比,液滴韦伯数,和液滴池的可溶解性。爬面射流的机理与Worthington射流完全不同:液池中的液体沿液滴表面爬升,形成液层,液层在液滴顶点处汇聚,产生爬面射流。这种表面爬升喷气机具有非常高的速度,即,比液滴冲击速度高一个数量级。还分析了冲击速度、液滴粘度、液滴尺寸和表面张力对爬面射流的影响。这项研究不仅为液滴和射流动力学机制提供了物理见解,而且有助于在许多相关应用中优化液滴撞击过程。

英文摘要:

It is generally accepted that the Worthington jet occurs when a droplet impacts onto a liquid pool. However, in this experimental study of the impact of viscous droplets onto a less-viscous liquid pool, we identify another jet besides the Worthington jet, forming a two-jet phenomenon. The two jets, a surface-climbing jet and the Worthington jet, may appear successively during one impact event. By carefully tuning the impact condition, we find that the two-jet phenomenon is jointly controlled by the droplet-pool viscosity ratio, the droplet Weber number, and the droplet-pool miscibility. The mechanism of the surface-climbing jet is completely different from that of the Worthington jet: the liquid in the pool climbs along the surface of the droplet and forms a liquid layer which converges at the droplet apex and produces the surface-climbing jet. This surface-climbing jet has a very high speed, i.e., an order of magnitude higher than the droplet impact speed. The effects of the impact speed, droplet viscosity, droplet size, and surface tension on the surface-climbing jet are also analysed. This study does not only provide physical insights into the mechanism of droplet and jet dynamics, but also be helpful in the optimisation of the droplet impact process in many relevant applications.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑