Journal article
Lock‐exchange gravity currents with a low volume of release propagating over an array of obstacles
Journal of Geophysical Research: Oceans, Vol.119(5), pp.2752-2768
05/2014
DOI: 10.1002/2013JC009721
Abstract
The study discusses, based on high‐resolution 3‐D large eddy simulation results, the evolution of lock‐exchange Boussinesq gravity currents with a low volume of release (LVR) propagating over an array of identical two‐dimensional (2‐D) obstacles (large roughness features in the form of dunes and ribs corresponding to eroded substrates) in a rectangular horizontal channel. The study analyzes the effect of the shape and height of the roughness elements and scale effects between Reynolds numbers at which most laboratory experiments of lock‐exchange currents are conducted and Reynolds numbers closer to field‐scale currents in geophysical applications on the temporal variation of the front velocity, mixing, and flow structure within the gravity current. The temporal evolution of the flow instabilities (e.g., Kelvin‐Helmholtz billows, forward and backward propagating interfacial waves forming as a result of the interaction of the front of the current with the obstacles) and bed friction velocity distributions are analyzed during the different stages of the evolution of the current. The focus is on the later stages of the propagation of LVR currents, after the transition to the self‐similar drag‐dominated regime has started. The differences between the evolution and structure of gravity currents with a low and a high volume of release are highlighted.
Key Points
Discuss structure of gravity currents in drag‐dominated regime
Evolution of currents is significantly affected by eroded substrate
Effect of interfacial waves generated by interaction with eroded substrate
Details
- Title: Subtitle
- Lock‐exchange gravity currents with a low volume of release propagating over an array of obstacles
- Creators
- Talia Tokyay - University of IowaGeorge Constantinescu - University of IowaEckart Meiburg - University of California at Santa Barbara
- Resource Type
- Journal article
- Publication Details
- Journal of Geophysical Research: Oceans, Vol.119(5), pp.2752-2768
- DOI
- 10.1002/2013JC009721
- ISSN
- 2169-9275
- eISSN
- 2169-9291
- Number of pages
- 17
- Grant note
- NSF (CBET‐0854338 ; CBET‐1067847 ; OCE‐1061300)
- Language
- English
- Date published
- 05/2014
- Academic Unit
- Civil and Environmental Engineering
- Record Identifier
- 9983991950102771
Metrics
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