Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 10 of 10 for “"vertical vorticity"”.
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Investigation of mean flow and vertical vorticity in turbulent convection using spectral simulations on massively parallel processors
… rectangular box with horizontal-to-vertical aspect ratio equal to four. This domain is periodic in the horizontal directions, and the top and bottom boundaries are isothermal, no-slip, impermeable walls. The flow-fields considered here range from steady horizontally-oriented …
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Tornadogenesis And Tornadogenesis Failure In Numerically Simulated Supercells
… tornadoes. A trajectory analysis found that vertical vorticity was generated in rising parcels as they ascended towards the tornado, and also by parcels that descended from aloft. However, large positive vertical vorticity was only produced after the parcels reached the surface. The most …
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Insights into tornadogenesis and tornado dynamics from idealized simulations
… studies which suggest that all supercells have vertical vorticity maxima which could be intensified to tornado strength, but that the presence of a robust and strong low-level mesocyclone is the critical factor deciding about tornadogenesis success. To test this conclusion, the relative …
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The Role of Preexisting Airmass Boundaries in the Maintenance and Rotation of Deep Convection in a High -Cape, Low -Shear Environment
… strong, temporally coherent near-surface vertical vorticity required the horizontal shear associated with either preexisting boundary.
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Effects of environmental shear and buoyancy on simulated supercell interactions
This study examines the role that buoyancy and vertical wind shear play in modulating the relationship between storm interactions and storm severity. Using an idealized numerical model, 240 supercell interactions are simulated under systematically varied amounts of buoyancy and vertical wind shear. …
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Storm mergers and their role in tornado genesis during the 2011 Joplin storm
… more favorable for rapid intensification of vertical vorticity at the surface than found in the surrounding environment. Following the work of Lemon (1976) and Lee et al. (2006), this study uses high-resolution WRF simulations to simulate and understand the significance of storm mergers in …
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Interaction of an upper-tropospheric jet with a squall line originating along a cold frontal boundary
… and deviations in the jet-level flow. The vertical transport of low momentum air from the boundary layer via convective updrafts is shown to significantly decelerate jet-level flow. The convective updrafts are also found to tilt baroclinically generated horizontal shear into the vertical, …
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Observations of misovortices within the 7 January 2014 Long Lake-Axis-Parallel lake-effect snow band during the Ontario Winter Lake-effect Systems Project
… which corresponds to the region of maximum vertical velocities. One particular band from the OWLeS Project, in which an abundance of misovortices developed, occurred on 7 January 2014. Steiger et al. (2013) postulated that the release of horizontal shearing instability (HSI) was the main …
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Mesoscale and stormscale ingredients of tornadic supercells producing long-track tornadoes in the 2011 Alabama super outbreak
… and Droegemeier (2002). Analysis scripts tracked vertical vorticity maxima, quantifying mesocyclone cycle strength, duration, updraft speed, and other associated properties. Case-study simulations have been used to understand the mesoscale forcing and environmental changes along storm tracks. A …
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Hydrodynamics of flexible-body swimming motions
… the nonlinear dynamics of thin shear layer vorticity shed from an arbitrary number of predefined wake separation edges. The integrated performance quantities and the near-body unsteady flow features are corroborated through experimental comparisons. Employing this numeric scheme for a …