Experimental study of liquid drop impact onto a powder surface

J. O. Marston, S. T. Thoroddsen, W. K. Ng, R. B.H. Tan

Research output: Contribution to journalArticlepeer-review

61 Scopus citations

Abstract

The initial dynamics of liquid drop impact onto powder surfaces is studied experimentally using high-speed photography. For a range of bed packing fractions, φ, liquid physical properties and impact velocities, ui, we observe a variety of phenomena that can be representative of a hydrophobic surface, a rough surface or a porous medium. The solids packing fraction in the bed, 0.38≤φ≤0.65, and the impact Weber number, 3.5≤We=ρDui2/φ≤750, (where ρ, D and φ are the drop density, diameter and surface tension respectively) are shown to be the critical parameters governing the outcome of an impact. For high packing fractions, φ≳0.5, we show that the observed spreading, rebound and splashing can be broadly characterised in terms of the Weber number while for looser packing fractions, φ≲0.5, we observe powder ejectas and provide a qualitative description of the granule nucleation at the centre of the impact sites.

Original languageEnglish
Pages (from-to)223-236
Number of pages14
JournalPowder Technology
Volume203
Issue number2
DOIs
StatePublished - Nov 2010

Keywords

  • Drop impact
  • Granulation
  • High-speed imaging
  • Nucleation

Fingerprint

Dive into the research topics of 'Experimental study of liquid drop impact onto a powder surface'. Together they form a unique fingerprint.

Cite this