Experimental investigation of instability phases of a laminar vortex ring, in light of comparable instability events in turbulent shear layer, boundary layer, and channel flows
Abstract
The laminar flow in a vortex is primarily determined by the toroidal laminar vortex core, the ondulatory flow by the ondulated laminar core, and the turbulent flow by the turbulent oscillating core. Inside these three global vortex flows, locally or globally unstable secondary vortices, and helix and double-helix flows are formed. A turbulence model was established in which turbulent flows consist of a complex organized vortex hierarchy and develop from an invarying degree, rhythmic sequence of unstable, laminar vortices as a result of an evolutional process.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- October 1980
- Bibcode:
- 1980STIN...8214489S
- Keywords:
-
- Flow Characteristics;
- Flow Stability;
- Turbulent Flow;
- Vortex Rings;
- Boundary Layer Flow;
- Channel Flow;
- Flow Visualization;
- Hierarchies;
- Laminar Flow;
- Oscillating Flow;
- Shear Layers;
- Turbulence Models;
- Vortex Generators;
- Fluid Mechanics and Heat Transfer