Measurements of entrainment and mixng in turbulent jets

Werner Dahm, P. E. Dimotakis

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

An experimental investigation of entrainment and mixing in the self-similar far field of an axisymmetric free turbulent jet in water is presented. Length and time scales for the flame length fluctuations of reacting jets are shown to be approximately equal to the Local characteristic large scale length and time of the flow. It is also shown that instantaneous radial profiles of concentration across the jet do not resemble the mean concentration profile, indicating that the mean profile is a poor representation of the mixed fluid states within the jet. These instantaneous profiles also show that unmixed ambient fluid is transported throughout the entire extent of the jet, and that the mixed fluid composition within the jet can be fairly uniform in regions extending across a large part of the local jet diameter. Lastly, the amount of unmixed ambient fluid on the jet centerline is found to vary roughly periodically with a period approximately equal to the local characteristic large scale time of the flow. These results suggest that large scale transport mechanisms, displaying a characteristic organization, play an important role in entrainment and mixing in the far field of turbulent jets.

Original languageEnglish (US)
Title of host publicationAlAA 23rd Aerospace Sciences Meeting, 1985
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
StatePublished - 1985
Externally publishedYes
EventAlAA 23rd Aerospace Sciences Meeting, 1985 - Reno, United States
Duration: Jan 14 1985Jan 17 1985

Other

OtherAlAA 23rd Aerospace Sciences Meeting, 1985
CountryUnited States
CityReno
Period1/14/851/17/85

Fingerprint

Fluids
Chemical analysis
Water

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Dahm, W., & Dimotakis, P. E. (1985). Measurements of entrainment and mixng in turbulent jets. In AlAA 23rd Aerospace Sciences Meeting, 1985 American Institute of Aeronautics and Astronautics Inc, AIAA.

Measurements of entrainment and mixng in turbulent jets. / Dahm, Werner; Dimotakis, P. E.

AlAA 23rd Aerospace Sciences Meeting, 1985. American Institute of Aeronautics and Astronautics Inc, AIAA, 1985.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Dahm, W & Dimotakis, PE 1985, Measurements of entrainment and mixng in turbulent jets. in AlAA 23rd Aerospace Sciences Meeting, 1985. American Institute of Aeronautics and Astronautics Inc, AIAA, AlAA 23rd Aerospace Sciences Meeting, 1985, Reno, United States, 1/14/85.
Dahm W, Dimotakis PE. Measurements of entrainment and mixng in turbulent jets. In AlAA 23rd Aerospace Sciences Meeting, 1985. American Institute of Aeronautics and Astronautics Inc, AIAA. 1985
Dahm, Werner ; Dimotakis, P. E. / Measurements of entrainment and mixng in turbulent jets. AlAA 23rd Aerospace Sciences Meeting, 1985. American Institute of Aeronautics and Astronautics Inc, AIAA, 1985.
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