External intermittency simulation in turbulent round jets
External intermittency simulation in turbulent round jets
Direct numerical and large eddy simulation (DNS and LES) are applied to study passive scalar mixing and intermittency in turbulent round jets. Both simulation techniques are applied to the case of a low Reynolds number jet with Re = 2,400, whilst LES is also used to predict a high Re = 68,000 flow. Comparison between time-averaged results for the scalar field of the low Re case demonstrate reasonable agreement between the DNS and LES, and with experimental data and the predictions of other authors. Scalar probability density functions (pdfs) for this jet derived from the simulations are also in reasonable accord, although the DNS results demonstrate the more rapid influence of scalar intermittency with radial distance in the jet. This is reflected in derived intermittency profiles, with LES generally giving profiles that are too broad compared to equivalent DNS results, with too low a rate of decay with radial distance. In contrast, good agreement is in general found between LES predictions and experimental data for the mixing field, scalar pdfs and external intermittency in the high Reynolds number jet. Overall, the work described indicates that improved sub-grid scale modelling for use with LES may be beneficial in improving the accuracy of external intermittency predictions by this technique over the wide range of Reynolds numbers of practical interest.
dns, les, scalar field, intermittency, round jet
385-406
Gilliland, T.
53f33de8-72ac-4f04-b119-e99af931d76a
Ranga Dinesh, K.K.J.
6454b22c-f505-40f9-8ad4-a1168e8f87cd
Fairweather, M.
7df85332-8495-4751-b50f-2872adc1f89e
Falle, S.A.E.G.
dcf64ade-c324-4397-ac5c-d64ac23e524f
Jenkins, K.W.
4ca70a5c-46dd-40bf-ae46-9efa3790f8ea
Savil, A.M.
b9eed4ae-9337-45e9-a177-96fd1bed97b6
September 2012
Gilliland, T.
53f33de8-72ac-4f04-b119-e99af931d76a
Ranga Dinesh, K.K.J.
6454b22c-f505-40f9-8ad4-a1168e8f87cd
Fairweather, M.
7df85332-8495-4751-b50f-2872adc1f89e
Falle, S.A.E.G.
dcf64ade-c324-4397-ac5c-d64ac23e524f
Jenkins, K.W.
4ca70a5c-46dd-40bf-ae46-9efa3790f8ea
Savil, A.M.
b9eed4ae-9337-45e9-a177-96fd1bed97b6
Gilliland, T., Ranga Dinesh, K.K.J. and Fairweather, M. et al.
(2012)
External intermittency simulation in turbulent round jets.
Flow Turbulence and Combustion, 89 (3), .
(doi:10.1007/s10494-012-9403-2).
Abstract
Direct numerical and large eddy simulation (DNS and LES) are applied to study passive scalar mixing and intermittency in turbulent round jets. Both simulation techniques are applied to the case of a low Reynolds number jet with Re = 2,400, whilst LES is also used to predict a high Re = 68,000 flow. Comparison between time-averaged results for the scalar field of the low Re case demonstrate reasonable agreement between the DNS and LES, and with experimental data and the predictions of other authors. Scalar probability density functions (pdfs) for this jet derived from the simulations are also in reasonable accord, although the DNS results demonstrate the more rapid influence of scalar intermittency with radial distance in the jet. This is reflected in derived intermittency profiles, with LES generally giving profiles that are too broad compared to equivalent DNS results, with too low a rate of decay with radial distance. In contrast, good agreement is in general found between LES predictions and experimental data for the mixing field, scalar pdfs and external intermittency in the high Reynolds number jet. Overall, the work described indicates that improved sub-grid scale modelling for use with LES may be beneficial in improving the accuracy of external intermittency predictions by this technique over the wide range of Reynolds numbers of practical interest.
Text
FTC_2012.pdf
- Version of Record
Restricted to Repository staff only
Request a copy
More information
e-pub ahead of print date: 14 July 2012
Published date: September 2012
Keywords:
dns, les, scalar field, intermittency, round jet
Organisations:
Engineering Science Unit
Identifiers
Local EPrints ID: 347360
URI: http://eprints.soton.ac.uk/id/eprint/347360
ISSN: 1386-6184
PURE UUID: f37bce68-ebde-452d-9cf6-65fa983a258e
Catalogue record
Date deposited: 24 Jan 2013 14:19
Last modified: 15 Mar 2024 03:46
Export record
Altmetrics
Contributors
Author:
T. Gilliland
Author:
M. Fairweather
Author:
S.A.E.G. Falle
Author:
K.W. Jenkins
Author:
A.M. Savil
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics
