Break-up dynamics and drop size distributions created from spiralling liquid jets

Research output: Contribution to journalArticle

Abstract

The dynamics of the break-up of spiralling jets of Newtonian liquids were visualised. The jets were created from orifices at the bottom of a 0.085-m-diameter can rotating about its vertical axis and imaged using a high-speed camera. The effects of liquid dynamic viscosity (0.001-0.09 Pa s), rotation rate (5-31 rad s(-1)) and orifice size (0.001 and 0.003 m) upon the jet break-up and drop size distributions produced in the Rayleigh regime were investigated. The ranges of dimensionless parameters were 1 <Re <10(3), 0.2 <Rb <4, 0.5 <We <25 and 5 x 10(-3) <Oh <4 x 10(-1). Four generic break-up modes identified were a strong function of dynamic viscosity and jet exit velocity. A flow pattern map of Ohnesorge number against Weber number enabled prediction of these modes. Increasing the can rotation rate increases jet exit velocity due to centrifugal forces and the trajectory of the jet becomes more curved. The break-up dynamics of the jets were non-linear, although some agreement between measured break-up lengths with the linear stability analysis developed previously was noted at low Reynolds numbers. A non-linear theoretical analysis is required to elucidate the important features. (C) 2004 Elsevier Ltd. All rights reserved.

Details

Original languageEnglish
Pages (from-to)499-520
Number of pages22
JournalInternational Journal of Multiphase Flow
Volume30
Issue number5
Publication statusPublished - 1 May 2004

Keywords

  • prilling, high-speed imaging, drop size distribution, surface tension instability, jet break-up, spiralling jet