Onset of stratification in a mixed layer subjected to a stabilizing buoyancy flux

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The formation of a thermocline in a water column, in which shear-free turbulence is generated both at the surface and bottom, and a stabilizing buoyancy flux is imposed at the surface, is studied using a laboratory experiment and a numerical model with the aim of understanding the formation of a tidal front in coastal seas. The results show that the formation of a thermocline, which always occurs in the absence of bottom mixing, is inhibited and the water column maintains a vertically mixed state, when bottom mixing becomes sufficiently strong. It is found from both experimental and numerical results that the criterion for the formation of a thermocline is determined by the balance between the rate of work that is necessary to maintain a mixed state against the formation of stratification by the buoyancy flux and the turbulent kinetic energy flux from the bottom supplied to the depth of thermocline formation. The depth of the thermocline, when it is formed, is found to decrease with bottom mixing.

Original languageEnglish
Pages (from-to)27-46
Number of pages20
JournalJournal of Fluid Mechanics
Volume304
DOIs
Publication statusPublished - Dec 1995
Externally publishedYes

Fingerprint

thermoclines
stratification
Buoyancy
buoyancy
Temperature distribution
Fluxes
Kinetic energy
Water
Numerical models
Turbulence
water
kinetic energy
turbulence
shear
Experiments

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Onset of stratification in a mixed layer subjected to a stabilizing buoyancy flux. / Noh, Y.

In: Journal of Fluid Mechanics, Vol. 304, 12.1995, p. 27-46.

Research output: Contribution to journalArticle

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