Hostname: page-component-7c8c6479df-8mjnm Total loading time: 0 Render date: 2024-03-28T11:08:41.988Z Has data issue: false hasContentIssue false

Impact jetting by a solid sphere

Published online by Cambridge University Press:  27 January 2004

S. T. THORODDSEN
Affiliation:
Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576
T. G. ETOH
Affiliation:
Civil and Environmental Engineering, Kinki University, Higashi-Osaka 577-8502, Japan
K. TAKEHARA
Affiliation:
Civil and Environmental Engineering, Kinki University, Higashi-Osaka 577-8502, Japan
Y. TAKANO
Affiliation:
Civil and Environmental Engineering, Kinki University, Higashi-Osaka 577-8502, Japan

Abstract

We use a novel ultra-high-speed video camera to study the initial stage of the impact of a solid sphere onto a liquid surface, finding a high-speed horizontal jet which emerges immediately following the intial contact. For ${\hbox{\it Re}} > 2 \times 10^4$ the jet emerges when the horizontal contact between the sphere and the liquid is only 12% of its diameter. For the largest Reynolds numbers this jet can travel at more than 30 times the impact velocity of the sphere. This jetting occurs sooner and at much higher normalized velocities than has been observed previously. The breakup of the jet into a spray of droplets sometimes occurs through formation of pockets in the liquid sheet. Early in the impact, the energy transferred to the jet and the subsequent spray sheet is estimated to be much larger than the energy associated with the added mass inside the liquid pool. The jetting will therefore greatly increase the initial impact force on the sphere.

Type
Papers
Copyright
© 2004 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)