Water entry of spheres into a rotating liquid

Lei Yi, Shuai Li, Hechuan Jiang, Detlef Lohse, Chao Sun, Varghese Mathai*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

The transient cavity dynamics during water entry of a heavy, non-rotating sphere impacting a rotating pool of liquid is studied experimentally, numerically and theoretically. We show that the pool rotation advances the transition of the cavity type - from deep seal to surface seal - marked by a reduction in the transitional Froude number. The role of the dimensionless rotational number on the transient cavity dynamics is unveiled, where is the sphere radius, the angular speed of the liquid and the impact velocity. The rotating background liquid has two discernible effects on the cavity evolution. Firstly, an increase in the underwater pressure field due to centripetal effects; and secondly, a reduction in the pressure of airflow in the cavity neck near the water surface. The non-dimensional pinch-off time of the deep seal shows a robust power-law dependence on the Froude number, but with a reducing prefactor for increasing. Our findings reveal that the effects of a rotating background liquid on the water entry can be traced back to the subtle differences in the initial stage splash and the near-surface cavity dynamics.

Original languageEnglish
Article numberR1
JournalJournal of fluid mechanics
Volume912
DOIs
Publication statusPublished - 10 Apr 2021

Keywords

  • UT-Hybrid-D
  • flow-structure interactions

Fingerprint Dive into the research topics of 'Water entry of spheres into a rotating liquid'. Together they form a unique fingerprint.

Cite this