Advanced

Mixing in circular and non-circular jets in crossflow

Salewski, Mirko LU ; Stankovic, Dragan LU and Fuchs, Laszlo LU (2008) In Flow Turbulence and Combustion 80(2). p.255-283
Abstract
Coherent structures and mixing in the flow field of a jet in crossflow have been studied using computational (large eddy simulation) and experimental (particle image velocimetry and laser-induced fluorescence) techniques. The mean scalar fields and turbulence statistics as determined by both are compared for circular, elliptic, and square nozzles. For the latter configurations, effects of orientation are considered. The computations reveal that the distribution of a passive scalar in a cross-sectional plane can be single- or double-peaked, depending on the nozzle shape and orientation. A proper orthogonal decomposition of the transverse velocity indicates that coherent structures may be responsible for this phenomenon. Nozzles which have a... (More)
Coherent structures and mixing in the flow field of a jet in crossflow have been studied using computational (large eddy simulation) and experimental (particle image velocimetry and laser-induced fluorescence) techniques. The mean scalar fields and turbulence statistics as determined by both are compared for circular, elliptic, and square nozzles. For the latter configurations, effects of orientation are considered. The computations reveal that the distribution of a passive scalar in a cross-sectional plane can be single- or double-peaked, depending on the nozzle shape and orientation. A proper orthogonal decomposition of the transverse velocity indicates that coherent structures may be responsible for this phenomenon. Nozzles which have a single-peaked distribution have stronger modes in transverse direction. The global mixing performance is superior for these nozzle types. This is the case for the blunt square nozzle and for the elliptic nozzle with high aspect ratio. It is further demonstrated that the flow field contains large regions in which a passive scalar is transported up the mean gradient (counter-gradient transport) which implies failure of the gradient diffusion hypothesis. (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
mixing, jet in crossflow, transverse jet, nozzle, shape, coherent structures
in
Flow Turbulence and Combustion
volume
80
issue
2
pages
255 - 283
publisher
Springer
external identifiers
  • wos:000252942900005
  • scopus:39149094625
ISSN
1573-1987
DOI
10.1007/s10494-007-9119-x
language
English
LU publication?
yes
id
771ceb58-194d-437e-bbb5-5a288e306b8e (old id 1198720)
date added to LUP
2008-09-10 16:27:32
date last changed
2017-10-22 03:37:03
@article{771ceb58-194d-437e-bbb5-5a288e306b8e,
  abstract     = {Coherent structures and mixing in the flow field of a jet in crossflow have been studied using computational (large eddy simulation) and experimental (particle image velocimetry and laser-induced fluorescence) techniques. The mean scalar fields and turbulence statistics as determined by both are compared for circular, elliptic, and square nozzles. For the latter configurations, effects of orientation are considered. The computations reveal that the distribution of a passive scalar in a cross-sectional plane can be single- or double-peaked, depending on the nozzle shape and orientation. A proper orthogonal decomposition of the transverse velocity indicates that coherent structures may be responsible for this phenomenon. Nozzles which have a single-peaked distribution have stronger modes in transverse direction. The global mixing performance is superior for these nozzle types. This is the case for the blunt square nozzle and for the elliptic nozzle with high aspect ratio. It is further demonstrated that the flow field contains large regions in which a passive scalar is transported up the mean gradient (counter-gradient transport) which implies failure of the gradient diffusion hypothesis.},
  author       = {Salewski, Mirko and Stankovic, Dragan and Fuchs, Laszlo},
  issn         = {1573-1987},
  keyword      = {mixing,jet in crossflow,transverse jet,nozzle,shape,coherent structures},
  language     = {eng},
  number       = {2},
  pages        = {255--283},
  publisher    = {Springer},
  series       = {Flow Turbulence and Combustion},
  title        = {Mixing in circular and non-circular jets in crossflow},
  url          = {http://dx.doi.org/10.1007/s10494-007-9119-x},
  volume       = {80},
  year         = {2008},
}