Statistics of the turbulent/non-turbulent interface in a spatially evolving mixing layer

Handle URI:
http://hdl.handle.net/10754/277454
Title:
Statistics of the turbulent/non-turbulent interface in a spatially evolving mixing layer
Authors:
Cristancho, Juan
Abstract:
The thin interface separating the inner turbulent region from the outer irrotational fluid is analyzed in a direct numerical simulation of a spatially developing turbulent mixing layer. A vorticity threshold is defined to detect the interface separating the turbulent from the non-turbulent regions of the flow, and to calculate statistics conditioned on the distance from this interface. Velocity and passive scalar statistics are computed and compared to the results of studies addressing other shear flows, such as turbulent jets and wakes. The conditional statistics for velocity are in remarkable agreement with the results for other types of free shear flow available in the literature. In addition, a detailed analysis of the passive scalar field (with Sc 1) in the vicinity of the interface is presented. The scalar has a jump at the interface, even stronger than that observed for velocity. The strong jump for the scalar has been observed before in the case of high Schmidt number, but it is a new result for Schmidt number of order one. Finally, the dissipation for the kinetic energy and the scalar are presented. While the kinetic energy dissipation has its maximum far from the interface, the scalar dissipation is characterized by a strong peak very close to the interface.
Advisors:
Bisetti, Fabrizio ( 0000-0001-5162-7805 )
Committee Member:
Samtaney, Ravi ( 0000-0002-4702-6473 ) ; Thoroddsen, Sigurdur T ( 0000-0001-6997-4311 )
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Program:
Mechanical Engineering
Issue Date:
Dec-2012
Type:
Thesis
Appears in Collections:
Theses; Physical Sciences and Engineering (PSE) Division; Mechanical Engineering Program

Full metadata record

DC FieldValue Language
dc.contributor.advisorBisetti, Fabrizioen
dc.contributor.authorCristancho, Juanen
dc.date.accessioned2013-03-30T07:33:57Z-
dc.date.available2013-03-30T07:33:57Z-
dc.date.issued2012-12en
dc.identifier.urihttp://hdl.handle.net/10754/277454en
dc.description.abstractThe thin interface separating the inner turbulent region from the outer irrotational fluid is analyzed in a direct numerical simulation of a spatially developing turbulent mixing layer. A vorticity threshold is defined to detect the interface separating the turbulent from the non-turbulent regions of the flow, and to calculate statistics conditioned on the distance from this interface. Velocity and passive scalar statistics are computed and compared to the results of studies addressing other shear flows, such as turbulent jets and wakes. The conditional statistics for velocity are in remarkable agreement with the results for other types of free shear flow available in the literature. In addition, a detailed analysis of the passive scalar field (with Sc 1) in the vicinity of the interface is presented. The scalar has a jump at the interface, even stronger than that observed for velocity. The strong jump for the scalar has been observed before in the case of high Schmidt number, but it is a new result for Schmidt number of order one. Finally, the dissipation for the kinetic energy and the scalar are presented. While the kinetic energy dissipation has its maximum far from the interface, the scalar dissipation is characterized by a strong peak very close to the interface.en
dc.language.isoenen
dc.subjectInterfaceen
dc.subjectMixing Layeren
dc.subjectStatisticsen
dc.subjectTurbulenceen
dc.titleStatistics of the turbulent/non-turbulent interface in a spatially evolving mixing layeren
dc.typeThesisen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberSamtaney, Ravien
dc.contributor.committeememberThoroddsen, Sigurdur Ten
thesis.degree.disciplineMechanical Engineeringen
thesis.degree.nameMaster of Scienceen
dc.person.id118399en
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