Intermittent bursting of turbulence in a stable boundary layer with low-level jet

Yuji Ohya, Reina Nakamura, Takanori Uchida

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

The atmospheric stable boundary layer (SBL) with a low-level jet is simulated experimentally using a thermally stratified wind tunnel. The turbulence structure and flow characteristics are investigated by simultaneous measurements of velocity and temperature fluctuations and by flow visualization. Attention is focused on the effect of strong wind shear due to a low-level jet on stratified boundary layers with strong stability. Occasional bursting of turbulence in the lower portion of the boundary layer can be found in the SBL with strong stability. This bursting originates aloft away from the surface and transports fluid with relatively low velocity and temperature upward and fluid with relatively high velocity and temperature downward. Furthermore, the relationship between the occurrence of turbulence bursting and the local gradient Richardson number (Ri) is investigated. The Ri becomes larger than the critical Ri, Ricr = 0.25, in quiescent periods. On the other hand, the Ri number becomes smaller than Ricr during bursting events.

Original languageEnglish
Pages (from-to)349-363
Number of pages15
JournalBoundary-Layer Meteorology
Volume126
Issue number3
DOIs
Publication statusPublished - Mar 1 2008

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boundary layer
turbulence
Richardson number
fluid
temperature
wind shear
wind tunnel
visualization

All Science Journal Classification (ASJC) codes

  • Atmospheric Science

Cite this

Intermittent bursting of turbulence in a stable boundary layer with low-level jet. / Ohya, Yuji; Nakamura, Reina; Uchida, Takanori.

In: Boundary-Layer Meteorology, Vol. 126, No. 3, 01.03.2008, p. 349-363.

Research output: Contribution to journalArticle

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