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Effect of cavity geometry on fuel transport and mixing processes in a scramjet combustor

Cai, Zun; Sun, Mingbo; Wang, Zhenguo and Bai, Xue Song LU (2018) In Aerospace Science and Technology 80. p.309-314
Abstract

This paper reports a numerical investigation on the effect of cavity geometry on fuel transport and mixing processes in a scramjet combustor with a single rear-wall-expansion cavity. The numerical solver and the LES methods were validated against available experimental data and the numerical results were shown in good agreement with the experiments. Effect of the cavity rear wall height on the non-reacting flow fields was then investigated. It was found that the vertical flow velocity of the region located right after the expansion wave starting from the cavity leading edge was increased significantly towards the cavity when lowering the rear wall height, leading to an enhanced fuel entrainment into the cavity. Subsequently, at a larger... (More)

This paper reports a numerical investigation on the effect of cavity geometry on fuel transport and mixing processes in a scramjet combustor with a single rear-wall-expansion cavity. The numerical solver and the LES methods were validated against available experimental data and the numerical results were shown in good agreement with the experiments. Effect of the cavity rear wall height on the non-reacting flow fields was then investigated. It was found that the vertical flow velocity of the region located right after the expansion wave starting from the cavity leading edge was increased significantly towards the cavity when lowering the rear wall height, leading to an enhanced fuel entrainment into the cavity. Subsequently, at a larger cavity expansion ratio, the mixture inside the cavity became more fuel-rich, giving rise to a deteriorated mixing environment. In addition, the cavity recirculation zone was further compressed and the turbulent flow and scalar dissipation inside the cavity would be enhanced, which were likely the reason causing the ignition failures and poor flame stabilizations. An optimal cavity expansion ratio for the maximum fuel entrainment was found in the present rig.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Cavity geometry, Fuel transport, Mixing efficiency, OpenFOAM, Rear wall height
in
Aerospace Science and Technology
volume
80
pages
6 pages
publisher
Elsevier Masson SAS
external identifiers
  • scopus:85050563768
ISSN
1270-9638
DOI
10.1016/j.ast.2018.07.028
language
English
LU publication?
yes
id
aea626c8-a593-480e-b54e-76908693d3f7
date added to LUP
2018-08-15 11:34:24
date last changed
2019-10-15 06:43:24
@article{aea626c8-a593-480e-b54e-76908693d3f7,
  abstract     = {<p>This paper reports a numerical investigation on the effect of cavity geometry on fuel transport and mixing processes in a scramjet combustor with a single rear-wall-expansion cavity. The numerical solver and the LES methods were validated against available experimental data and the numerical results were shown in good agreement with the experiments. Effect of the cavity rear wall height on the non-reacting flow fields was then investigated. It was found that the vertical flow velocity of the region located right after the expansion wave starting from the cavity leading edge was increased significantly towards the cavity when lowering the rear wall height, leading to an enhanced fuel entrainment into the cavity. Subsequently, at a larger cavity expansion ratio, the mixture inside the cavity became more fuel-rich, giving rise to a deteriorated mixing environment. In addition, the cavity recirculation zone was further compressed and the turbulent flow and scalar dissipation inside the cavity would be enhanced, which were likely the reason causing the ignition failures and poor flame stabilizations. An optimal cavity expansion ratio for the maximum fuel entrainment was found in the present rig.</p>},
  author       = {Cai, Zun and Sun, Mingbo and Wang, Zhenguo and Bai, Xue Song},
  issn         = {1270-9638},
  keyword      = {Cavity geometry,Fuel transport,Mixing efficiency,OpenFOAM,Rear wall height},
  language     = {eng},
  month        = {09},
  pages        = {309--314},
  publisher    = {Elsevier Masson SAS},
  series       = {Aerospace Science and Technology},
  title        = {Effect of cavity geometry on fuel transport and mixing processes in a scramjet combustor},
  url          = {http://dx.doi.org/10.1016/j.ast.2018.07.028},
  volume       = {80},
  year         = {2018},
}