Direct numerical simulation of intermittent turbulence under stably stratified conditions
In this paper, we simulate intermittent turbulence (also known as bursting events) in stably stratified open-channel flows using direct numerical simulation. Clear signatures of this intriguing phenomenon are observed for a range of stabilities. However, the spatiotemporal characteristics of intermi...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2015-07-01
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| Series: | Nonlinear Processes in Geophysics |
| Online Access: | http://www.nonlin-processes-geophys.net/22/447/2015/npg-22-447-2015.pdf |
| _version_ | 1818417569026015232 |
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| author | P. He S. Basu |
| author_facet | P. He S. Basu |
| author_sort | P. He |
| collection | DOAJ |
| description | In this paper, we simulate intermittent turbulence (also known as bursting
events) in stably stratified open-channel flows using direct numerical
simulation. Clear signatures of this intriguing phenomenon are observed for a
range of stabilities. However, the spatiotemporal characteristics of
intermittency are found to be strongly stability dependent. In general, the
bursting events are much more frequent near the bottom wall than in the
upper-channel region. A steady coexistence of laminar and turbulent flows is
detected at various horizontal planes in very stable cases. This spatially
intermittent pattern is found to propagate downstream and strongly correlate
with the temporal evolution of intermittency. Lastly, a long standing
hypothesis by Blackadar (1979), i.e., the strong connection between local stability
and intermittent turbulence, is corroborated by this modeling study. |
| first_indexed | 2024-12-14T12:08:52Z |
| format | Article |
| id | doaj.art-1c1dc9b19e8f47bfb90bf910e14a1779 |
| institution | Directory Open Access Journal |
| issn | 1023-5809 1607-7946 |
| language | English |
| last_indexed | 2024-12-14T12:08:52Z |
| publishDate | 2015-07-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Nonlinear Processes in Geophysics |
| spelling | doaj.art-1c1dc9b19e8f47bfb90bf910e14a17792022-12-21T23:01:47ZengCopernicus PublicationsNonlinear Processes in Geophysics1023-58091607-79462015-07-0122444747110.5194/npg-22-447-2015Direct numerical simulation of intermittent turbulence under stably stratified conditionsP. He0S. Basu1Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695, USADepartment of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695, USAIn this paper, we simulate intermittent turbulence (also known as bursting events) in stably stratified open-channel flows using direct numerical simulation. Clear signatures of this intriguing phenomenon are observed for a range of stabilities. However, the spatiotemporal characteristics of intermittency are found to be strongly stability dependent. In general, the bursting events are much more frequent near the bottom wall than in the upper-channel region. A steady coexistence of laminar and turbulent flows is detected at various horizontal planes in very stable cases. This spatially intermittent pattern is found to propagate downstream and strongly correlate with the temporal evolution of intermittency. Lastly, a long standing hypothesis by Blackadar (1979), i.e., the strong connection between local stability and intermittent turbulence, is corroborated by this modeling study.http://www.nonlin-processes-geophys.net/22/447/2015/npg-22-447-2015.pdf |
| spellingShingle | P. He S. Basu Direct numerical simulation of intermittent turbulence under stably stratified conditions Nonlinear Processes in Geophysics |
| title | Direct numerical simulation of intermittent turbulence under stably stratified conditions |
| title_full | Direct numerical simulation of intermittent turbulence under stably stratified conditions |
| title_fullStr | Direct numerical simulation of intermittent turbulence under stably stratified conditions |
| title_full_unstemmed | Direct numerical simulation of intermittent turbulence under stably stratified conditions |
| title_short | Direct numerical simulation of intermittent turbulence under stably stratified conditions |
| title_sort | direct numerical simulation of intermittent turbulence under stably stratified conditions |
| url | http://www.nonlin-processes-geophys.net/22/447/2015/npg-22-447-2015.pdf |
| work_keys_str_mv | AT phe directnumericalsimulationofintermittentturbulenceunderstablystratifiedconditions AT sbasu directnumericalsimulationofintermittentturbulenceunderstablystratifiedconditions |