Turbulence structure of stable boundary layers with a near-linear temperature profile

Yuji Ohya, Takanori Uchida

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

By using a thermally stratified wind tunnel, we have successfully simulated stably stratified boundary layers (SBL), in which the mean temperature increases upward almost linearly. We have investigated the flow structure and the effects of near-linear stable stratification on the transfer of momentum and heat. The vertical profiles of turbulence quantities exhibit different behaviour in two distinct stability regimes of the SBL flows with weak and strong stability. For weak stability cases, the turbulent transfer of momentum and heat is basically similar to that for neutral turbulent boundary layers, although it is weakened with increasing stability. For strong stability cases, on the other hand, the time-mean transfer is almost zero over the whole boundary-layer depth. However, the instantaneous turbulent transfer frequently occurs in both gradient and counter-gradient directions in the lower part of the boundary layer. This is due to the Kelvin-Helmholtz (K-H) shear instability and the rolling up and breaking of K-H waves. Moreover, the internal gravity waves are observed in the middle and upper parts of all stable boundary layers.

Original languageEnglish
Pages (from-to)19-38
Number of pages20
JournalBoundary-Layer Meteorology
Volume108
Issue number1
DOIs
Publication statusPublished - Jul 1 2003

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temperature profile
boundary layer
turbulence
momentum
turbulent boundary layer
flow structure
internal wave
wind tunnel
gravity wave
vertical profile
stratification
temperature

All Science Journal Classification (ASJC) codes

  • Atmospheric Science

Cite this

Turbulence structure of stable boundary layers with a near-linear temperature profile. / Ohya, Yuji; Uchida, Takanori.

In: Boundary-Layer Meteorology, Vol. 108, No. 1, 01.07.2003, p. 19-38.

Research output: Contribution to journalArticle

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