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Journal of Applied Mathematics and Statistical Applications | Volume: 1
August 23-24, 2018 | London, UK
Applied Physics
3
rd
International Conference on
Cavity collapse and jet generation during the droplet impact
Ken Yamamoto
Tokyo University of Science, Japan
F
ree surface of a droplet impacting on a surface deforms
significantly within a timescale of milliseconds. This large
deformation leads various phenomena such as spreading,
splashing, etc. It is well known that which phenomenon
will be occurred is determined by the impact velocity, liquid
viscosity, atmospheric pressure, surface tension, and the
surface characteristics. For instance, the droplet behaviour is
completely different when a droplet is dropped on a hydrophilic
surface and when it is dropped on a superhydrophobic surface.
On superhydrophobic surfaces, the droplet bounces off the
surface like a rubber ball at lowWeber number (which indicates
a significance of inertia over surface tension), whereas the
droplet spreads and sticks on hydrophilic surfaces at the same
impact condition.
The bounce motion on superhydrophobic surfaces can be
explained by low adhesive force of the wall surface and surface
tension that exerts on liquid interface to make it have less
surface area. However, ifwe increase the impact velocity, we can
observe interesting phenomenon: jetting. The jet, specifically
the Worthington jet, is generated because of a collapse of an
air cavity formed at the centre of the droplet. Furthermore, we
found that the jet velocity and the characteristic radius depends
on the impact velocity, which results from oscillations of the
droplet cap caused by the impact.
Speaker Biography
Ken Yamamoto has completed his PhD at the age of 29 years from Tokyo Metropolitan
University, Japan. He is an assistant professor of Tokyo University of Science, Japan. He
has over 10 publications that have been cited over 80 times.
e:
yam@rs.tus.ac.jp