Statistics and scaling of turbulence in a spatially developing mixing layer at Reλ = 250

Handle URI:
http://hdl.handle.net/10754/552109
Title:
Statistics and scaling of turbulence in a spatially developing mixing layer at Reλ = 250
Authors:
Attili, Antonio; Bisetti, Fabrizio ( 0000-0001-5162-7805 )
Abstract:
The turbulent flow originating from the interaction between two parallel streams with different velocities is studied by means of direct numerical simulation. Rather than the more common temporal evolving layer, a spatially evolving configuration, with perturbed laminar inlet conditions is considered. The streamwise evolution and the self-similar state of turbulence statistics are reported and compared to results available in the literature. The characteristics of the transitional region agree with those observed in other simulations and experiments of mixing layers originating from laminar inlets. The present results indicate that the transitional region depends strongly on the inlet flow. Conversely, the self-similar state of turbulent kinetic energy and dissipation agrees quantitatively with those in a temporal mixing layer developing from turbulent initial conditions [M. M. Rogers and R. D. Moser, “Direct simulation of a self-similar turbulent mixing layer,” Phys. Fluids6, 903 (1994)]. The statistical features of turbulence in the self-similar region have been analysed in terms of longitudinal velocity structure functions, and scaling exponents are estimated by applying the extended self-similarity concept. In the small scale range (60 < r/η < 250), the scaling exponents display the universal anomalous scaling observed in homogeneous isotropic turbulence. The hypothesis of isotropy recovery holds in the turbulent mixing layer despite the presence of strong shear and large-scale structures, independently of the means of turbulence generation. At larger scales (r/η > 400), the mean shear and large coherent structures result in a significant deviation from predictions based on homogeneous isotropic turbulence theory. In this second scaling range, the numerical values of the exponents agree quantitatively with those reported for a variety of other flows characterized by strong shear, such as boundary layers, as well as channel and wake flows.
KAUST Department:
Clean Combustion Research Center
Citation:
Statistics and scaling of turbulence in a spatially developing mixing layer at Reλ = 250 2012, 24 (3):035109 Physics of Fluids
Publisher:
AIP Publishing
Journal:
Physics of Fluids
Issue Date:
21-Mar-2012
DOI:
10.1063/1.3696302
Type:
Article
ISSN:
10706631
Additional Links:
http://scitation.aip.org/content/aip/journal/pof2/24/3/10.1063/1.3696302
Appears in Collections:
Articles; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorAttili, Antonioen
dc.contributor.authorBisetti, Fabrizioen
dc.date.accessioned2015-05-03T14:25:55Zen
dc.date.available2015-05-03T14:25:55Zen
dc.date.issued2012-03-21en
dc.identifier.citationStatistics and scaling of turbulence in a spatially developing mixing layer at Reλ = 250 2012, 24 (3):035109 Physics of Fluidsen
dc.identifier.issn10706631en
dc.identifier.doi10.1063/1.3696302en
dc.identifier.urihttp://hdl.handle.net/10754/552109en
dc.description.abstractThe turbulent flow originating from the interaction between two parallel streams with different velocities is studied by means of direct numerical simulation. Rather than the more common temporal evolving layer, a spatially evolving configuration, with perturbed laminar inlet conditions is considered. The streamwise evolution and the self-similar state of turbulence statistics are reported and compared to results available in the literature. The characteristics of the transitional region agree with those observed in other simulations and experiments of mixing layers originating from laminar inlets. The present results indicate that the transitional region depends strongly on the inlet flow. Conversely, the self-similar state of turbulent kinetic energy and dissipation agrees quantitatively with those in a temporal mixing layer developing from turbulent initial conditions [M. M. Rogers and R. D. Moser, “Direct simulation of a self-similar turbulent mixing layer,” Phys. Fluids6, 903 (1994)]. The statistical features of turbulence in the self-similar region have been analysed in terms of longitudinal velocity structure functions, and scaling exponents are estimated by applying the extended self-similarity concept. In the small scale range (60 < r/η < 250), the scaling exponents display the universal anomalous scaling observed in homogeneous isotropic turbulence. The hypothesis of isotropy recovery holds in the turbulent mixing layer despite the presence of strong shear and large-scale structures, independently of the means of turbulence generation. At larger scales (r/η > 400), the mean shear and large coherent structures result in a significant deviation from predictions based on homogeneous isotropic turbulence theory. In this second scaling range, the numerical values of the exponents agree quantitatively with those reported for a variety of other flows characterized by strong shear, such as boundary layers, as well as channel and wake flows.en
dc.publisherAIP Publishingen
dc.relation.urlhttp://scitation.aip.org/content/aip/journal/pof2/24/3/10.1063/1.3696302en
dc.rightsArchived with thanks to Physics of Fluids. © 2012 American Institute of Physics .[ http://dx.doi.org/10.1063/1.3696302 ]en
dc.titleStatistics and scaling of turbulence in a spatially developing mixing layer at Reλ = 250en
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalPhysics of Fluidsen
dc.eprint.versionPublisher's Version/PDFen
kaust.authorAttili, Antonioen
kaust.authorBisetti, Fabrizioen
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