TY - JOUR
T1 - Micro-splashing by drop impacts
AU - Thoroddsen, Sigurdur T
AU - Takehara, Kohsei
AU - Etoh, Takeharugoji
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: S.T.T. was partially supported by KAUST GCR AEA Grant 70000000028 (Fine-Resolution Printing).
PY - 2012/7/18
Y1 - 2012/7/18
N2 - We use ultra-high-speed video imaging to observe directly the earliest onset of prompt splashing when a drop impacts onto a smooth solid surface. We capture the start of the ejecta sheet travelling along the solid substrate and show how it breaks up immediately upon emergence from the underneath the drop. The resulting micro-droplets are much smaller and faster than previously reported and may have gone unobserved owing to their very small size and rapid ejection velocities, which approach 100 m s-1, for typical impact conditions of large rain drops. We propose a phenomenological mechanism which predicts the velocity and size distribution of the resulting microdroplets. We also observe azimuthal undulations which may help promote the earliest breakup of the ejecta. This instability occurs in the cusp in the free surface where the drop surface meets the radially ejected liquid sheet. © 2012 Cambridge University Press.
AB - We use ultra-high-speed video imaging to observe directly the earliest onset of prompt splashing when a drop impacts onto a smooth solid surface. We capture the start of the ejecta sheet travelling along the solid substrate and show how it breaks up immediately upon emergence from the underneath the drop. The resulting micro-droplets are much smaller and faster than previously reported and may have gone unobserved owing to their very small size and rapid ejection velocities, which approach 100 m s-1, for typical impact conditions of large rain drops. We propose a phenomenological mechanism which predicts the velocity and size distribution of the resulting microdroplets. We also observe azimuthal undulations which may help promote the earliest breakup of the ejecta. This instability occurs in the cusp in the free surface where the drop surface meets the radially ejected liquid sheet. © 2012 Cambridge University Press.
UR - http://hdl.handle.net/10754/562243
UR - https://www.cambridge.org/core/product/identifier/S0022112012002819/type/journal_article
UR - http://www.scopus.com/inward/record.url?scp=84871477048&partnerID=8YFLogxK
U2 - 10.1017/jfm.2012.281
DO - 10.1017/jfm.2012.281
M3 - Article
SN - 0022-1120
VL - 706
SP - 560
EP - 570
JO - Journal of Fluid Mechanics
JF - Journal of Fluid Mechanics
ER -