Advanced

Three-dimensional flow structures and droplet-gas mixing process of a liquid jet in supersonic crossflow

Li, Peibo LU ; Wang, Zhenguo; Bai, Xue Song LU ; Wang, Hongbo; Sun, Mingbo; Wu, Liyin and Liu, Chaoyang LU (2019) In Aerospace Science and Technology 90. p.140-156
Abstract

The mixing process of a liquid jet in supersonic crossflow with a Mach number of 2.1 was investigated numerically using large eddy simulation (LES) based on the Eulerian-Lagrangian method. The gas phase was described using the Navier-Stokes equations and the liquid phase was represented using discrete droplets, which were injected and tracked in the computational domain individually according to Newton's second law of motion. The KH (Kelvin-Helmholtz) breakup model was used to calculate the droplet stripping process, and the secondary breakup process was simulated by coupling the RT (Rayleigh-Taylor) breakup model and the TAB (Taylor Analogy Breakup) model. Two-way coupling was enforced to consider the momentum and energy exchange... (More)

The mixing process of a liquid jet in supersonic crossflow with a Mach number of 2.1 was investigated numerically using large eddy simulation (LES) based on the Eulerian-Lagrangian method. The gas phase was described using the Navier-Stokes equations and the liquid phase was represented using discrete droplets, which were injected and tracked in the computational domain individually according to Newton's second law of motion. The KH (Kelvin-Helmholtz) breakup model was used to calculate the droplet stripping process, and the secondary breakup process was simulated by coupling the RT (Rayleigh-Taylor) breakup model and the TAB (Taylor Analogy Breakup) model. Two-way coupling was enforced to consider the momentum and energy exchange between the gas and the droplets. It was found that the LES predicted spray characteristics, including spray penetration and cross-sectional distribution, agree reasonably well with the experiment. The major gas flow structures such as the bow shock, the large-scale vortices, and the recirculation zones were replicated successfully in the simulations. It was found that the gas flow structures have a significant effect on the mixing process of the droplets. The simulation results revealed that two sets of counter-rotating vortex pair (CVP) exist in the gas-liquid mixing region. Under the influence of CVP, part droplets were transported to the near wall region and subsequently to both sides of the core spray region. The formation mechanism of the CVP was analyzed by comparing the pressure gradient and the source term of droplets in the Navier-Stokes equations. Differences of the mixing process of liquid jet in supersonic crossflow, gas jet in supersonic crossflow and liquid jet in incompressible crossflow were identified.

(Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Counter-rotating vortex pair (CVP), Eulerian-Lagrangian, Large-eddy simulation, Liquid jet, Mixing process, Supersonic crossflow
in
Aerospace Science and Technology
volume
90
pages
17 pages
publisher
Elsevier Masson SAS
external identifiers
  • scopus:85064925865
ISSN
1270-9638
DOI
10.1016/j.ast.2019.04.024
language
English
LU publication?
yes
id
d22c353f-9bdf-4e28-bc2b-ba303f700608
date added to LUP
2019-05-13 12:37:52
date last changed
2019-06-04 03:57:54
@article{d22c353f-9bdf-4e28-bc2b-ba303f700608,
  abstract     = {<p>The mixing process of a liquid jet in supersonic crossflow with a Mach number of 2.1 was investigated numerically using large eddy simulation (LES) based on the Eulerian-Lagrangian method. The gas phase was described using the Navier-Stokes equations and the liquid phase was represented using discrete droplets, which were injected and tracked in the computational domain individually according to Newton's second law of motion. The KH (Kelvin-Helmholtz) breakup model was used to calculate the droplet stripping process, and the secondary breakup process was simulated by coupling the RT (Rayleigh-Taylor) breakup model and the TAB (Taylor Analogy Breakup) model. Two-way coupling was enforced to consider the momentum and energy exchange between the gas and the droplets. It was found that the LES predicted spray characteristics, including spray penetration and cross-sectional distribution, agree reasonably well with the experiment. The major gas flow structures such as the bow shock, the large-scale vortices, and the recirculation zones were replicated successfully in the simulations. It was found that the gas flow structures have a significant effect on the mixing process of the droplets. The simulation results revealed that two sets of counter-rotating vortex pair (CVP) exist in the gas-liquid mixing region. Under the influence of CVP, part droplets were transported to the near wall region and subsequently to both sides of the core spray region. The formation mechanism of the CVP was analyzed by comparing the pressure gradient and the source term of droplets in the Navier-Stokes equations. Differences of the mixing process of liquid jet in supersonic crossflow, gas jet in supersonic crossflow and liquid jet in incompressible crossflow were identified.</p>},
  author       = {Li, Peibo and Wang, Zhenguo and Bai, Xue Song and Wang, Hongbo and Sun, Mingbo and Wu, Liyin and Liu, Chaoyang},
  issn         = {1270-9638},
  keyword      = {Counter-rotating vortex pair (CVP),Eulerian-Lagrangian,Large-eddy simulation,Liquid jet,Mixing process,Supersonic crossflow},
  language     = {eng},
  pages        = {140--156},
  publisher    = {Elsevier Masson SAS},
  series       = {Aerospace Science and Technology},
  title        = {Three-dimensional flow structures and droplet-gas mixing process of a liquid jet in supersonic crossflow},
  url          = {http://dx.doi.org/10.1016/j.ast.2019.04.024},
  volume       = {90},
  year         = {2019},
}