Large impact velocities suppress the splashing of micron-sized droplets
Large impact velocities suppress the splashing of micron-sized droplets
复制标题
大的冲击速度抑制微米级液滴的飞溅
DOI：
10.1103/physrevfluids.6.023605
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发表时间：
2021
影响因子：
2.7
通讯作者：
J.M.
中科院分区：
文献类型：
--
作者：
Usawa;M.;Fujita;Y.;Tagawa;Y.;Riboux;G.;and Gordillo;J.M.
在这里，我们研究了在正常大气条件下，液滴从扩散到飞溅的转变，其辐射范围从毫米到数十微米，撞击到光滑干燥的部分润湿基材上。实验表明，越小，液滴飞溅所需的冲击速度越大，但如果用 、 、 和 表示界面张力系数、液体密度和气体分子的平均自由程，则飞溅受到抑制。该结果已针对两个不同的 Ohnesorge 数值进行了验证，该数表示液体粘度，仅使用液体和周围气体气氛的材料特性来定义。这一先验的意外发现的根本原因是，在许多实际条件下，液滴接触基底后喷射出的薄液膜是 Riboux 和 Gordillo [Phys.莱特牧师。 113, 024507 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.024507]。然后，对于足够大的值，薄片的厚度变得类似于气体分子的平均自由程，即，并且，在这些条件下，液滴的飞溅被抑制，因为导致液体使部分润湿的固体去湿的升力可以忽略不计。 G. Riboux 和 J. M. Gordillo [Phys.雷特牧师。 113, 024507 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.024507] 和 J. M. Gordillo 和 G. Riboux [J. 流体机械。 871，R3（2019）JFLSA70022-112010.1017/jfm.2019.396]一旦气动升力设置为零，即当。
Here we investigate the transition from spreading to splashing of drops with radiivarying from millimeters to tens of microns impacting onto a smooth and dry partially wetting substrate at normal atmospheric conditions. Experiments show that the smalleris, the larger the impact velocityfor the drop to splash needs to be but also that splash is inhibited if, with,, andindicating the interfacial tension coefficient, the liquid density, and the mean free path of gas molecules. This result has been validated for two different values of the Ohnesorge number, withindicating the liquid viscosity, defined using only the material properties of the liquid and of the surrounding gaseous atmosphere. The underlying reason for thisa prioriunexpected finding results from the fact that the thin liquid film ejected after the drop touches the substrate is, under many practical conditions,Riboux and Gordillo [Phys. Rev. Lett. 113, 024507 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.024507]. Then, for sufficiently large values of, the thickness of the lamella becomes similar to the mean free path of gas molecules, i.e.,, and, under these conditions, the splash of the drop is inhibited because the lift force causing the liquid to dewet the partially wetting solid is negligible. The spreading to splashing and the splashing to spreading transitions observed experimentally as the impact velocity is increased and the radii of the droplets is above a certain threshold value are very well predicted by the theory in G. Riboux and J. M. Gordillo [Phys. Rev. Lett. 113, 024507 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.024507] and J. M. Gordillo and G. Riboux [J. Fluid Mech. 871, R3 (2019)JFLSA70022-112010.1017/jfm.2019.396] once the aerodynamic lift force is set to zero for, i.e., when.
影响因子：
4.6
作者：
H. Onuki;Yuto Oi;Y. Tagawa
通讯作者：
H. Onuki;Yuto Oi;Y. Tagawa
影响因子：
3.7
作者：
J. Gordillo;H. Onuki;Y. Tagawa
通讯作者：
J. Gordillo;H. Onuki;Y. Tagawa