Hostname: page-component-6766d58669-h8lrw Total loading time: 0 Render date: 2026-05-21T13:46:11.767Z Has data issue: false hasContentIssue false

Particle dispersion induced by vortical interactions in a particle-laden upward jet with a partial crossflow

Published online by Cambridge University Press:  09 March 2021

Jooyeon Park
Affiliation:
Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
Hyungmin Park*
Affiliation:
Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea Institute of Advanced Machines and Design, Seoul National University, Seoul 08826, Korea
*
Email address for correspondence: hminpark@snu.ac.kr

Abstract

In the present study particle dispersions (concentrations) through vortical interactions are experimentally investigated for a particle-laden upward jet, with a horizontal crossflow covering a vertical range partially near the jet exit (Reynolds numbers of 1170–5200). We focus on the influences of the dynamics of counter-rotating vortex pairs existing in the flow on changes in the particle dispersion patterns, depending on the velocity (jet/crossflow) ratio and particle Stokes number ($St = 0.01\text {--}27.42$). Without crossflow, there is no dominant vortical structure along the horizontal direction; thus, the particles are not dispersed significantly out of the jet core in most cases, except for the case with the highest particle inertia (i.e. $St$). With crossflow, on the other hand, counter-rotating vortex pairs appear above the jet exit and become stronger as the velocity ratio decreases. With a lower velocity ratio, the vortices are tilted more toward the leeward side and dissipate faster. Driven by the vortex pairs, the drag force acting on the particles becomes stronger and, thus, particles with $St < 1.0$ are dragged out of the jet core following the rotation of the vortices. Those with $St \simeq 1.0$ are concentrated between the vortex pairs before the vortices collapse. When $St \gg 1.0$, particles are simply transported by the inertial effect. Finally, we suggest different regimes for particle dispersion (concentration) as classified by the Stokes number and velocity ratio, and elucidate their mechanisms, which are further extended to empirical particle dispersion models.

Information

Type
JFM Papers
Copyright
© The Author(s), 2021. Published by 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.)

Article purchase

Temporarily unavailable