Vortex rings impinging on permeable boundaries
Experiments with vortex rings impinging permeable and solid boundaries are presented in order to investigate the influence of permeability. Utilizing Particle Image Velocimetry, we compared the behaviour of a vortex ring impinging four different reticulated foams (with permeability k ~ 26 - 85 × 10-...
| Autores: | , , |
|---|---|
| Tipo de recurso: | artículo |
| Fecha de publicación: | 2015 |
| País: | España |
| Institución: | Universitat Politècnica de Catalunya (UPC) |
| Repositorio: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglés |
| OAI Identifier: | oai:upcommons.upc.edu:2117/26161 |
| Acceso en línea: | https://hdl.handle.net/2117/26161 https://dx.doi.org/10.1063/1.4906504 |
| Access Level: | acceso abierto |
| Palabra clave: | Vortex-motion Permeability Vortex rings Foams Rotating flows Boundary value problems Velocimetry Vòrtexs (Hidrodinàmica) Permeabilitat Àrees temàtiques de la UPC::Física::Física de fluids |
| Sumario: | Experiments with vortex rings impinging permeable and solid boundaries are presented in order to investigate the influence of permeability. Utilizing Particle Image Velocimetry, we compared the behaviour of a vortex ring impinging four different reticulated foams (with permeability k ~ 26 - 85 × 10-8 m2) and a solid boundary. Results show how permeability affects the stretching phenomena of the vortex ring and the formation and evolution of the secondary vortex ring with opposite sign. Moreover, permeability also affects the macroscopic no-slip boundary condition found on the solid boundary, turning it into an apparent slip boundary condition for the most permeable boundary. The apparent slip-boundary condition and the flux exchange between the ambient fluid and the foam are jointly responsible for both the modified formation of the secondary vortex and changes on the vortex ring diameter increase. |
|---|