Buoyancy-induced, columnar vortices
| العنوان: | Buoyancy-induced, columnar vortices |
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| المؤلفون: | Ari Glezer, Mark W. Simpson |
| المصدر: | Journal of Fluid Mechanics. 804:712-748 |
| بيانات النشر: | Cambridge University Press (CUP), 2016. |
| سنة النشر: | 2016 |
| مصطلحات موضوعية: | Materials science, Buoyancy, 010504 meteorology & atmospheric sciences, Mechanical Engineering, Airflow, Mechanics, engineering.material, Vorticity, Condensed Matter Physics, Kinetic energy, 01 natural sciences, 010305 fluids & plasmas, Vortex, Physics::Fluid Dynamics, Momentum, Boundary layer, Particle image velocimetry, Mechanics of Materials, Condensed Matter::Superconductivity, 0103 physical sciences, engineering, 0105 earth and related environmental sciences |
| الوصف: | A buoyancy-induced, columnar vortex is deliberately triggered in the unstably stratified air layer over a heated ground plane and is anchored within, and scales with, an azimuthal array of vertical, stator-like planar flow vanes that form an open-top enclosure and impart tangential momentum to the radially entrained air flow. The columnar vortex comprises three coupled primary flow domains: a spiraling surface momentum boundary layer of ground-heated air, an inner thermally driven vertical vortex core and an outer annular flow that is bounded by a helical shear layer and the vanes along its inner and outer edges, respectively, and by the spiraling boundary layer from below. In common with free buoyant columnar (dust devil) vortices that occur spontaneously over solar-heated terrain in the natural environment, the stationary anchored vortex is self-sustained by the conversion of the potential energy of the entrained surface-heated air layer to the kinetic energy of the induced vortical flow that persists as long as the thermal stratification is maintained. This conversion occurs as radial vorticity produced within the surface boundary layer is tilted vertically near the vortex centreline by the buoyant air to form the core of the columnar vortex. The structure and dynamics of the buoyant vortex are investigated using high-resolution stereo particle image velocimetry with specific emphasis on the evolution of the vorticity distributions and their effects on the characteristic scales of the ensuing vortex and on the kinetic energy of the induced flow. |
| تدمد: | 1469-7645 0022-1120 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::5790df82cd8b1e48cdcf67fa50389857 https://doi.org/10.1017/jfm.2016.541 |
| حقوق: | CLOSED |
| رقم الأكسشن: | edsair.doi...........5790df82cd8b1e48cdcf67fa50389857 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 14697645 00221120 |
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