Abstract
dc:description.abstractThe interaction of vortices passing near free and solid surfaces has been examined using direct numerical simulation (DNS). A computer code was developed which solves the unsteady, three-dimensional Navier-Stokes equations for incompressible flow. A critical element of the numerical scheme is the efficient solution of Poisson's equation. A state of the art solver based on multigrid techniques was developed which gives excellent convergence rates. The result is a tool capable of modeling complex three-dimensional flows in a variety of configurations. Three different flow fields have been examined in order to determine some of the complex interactions involved between a vortex and a surface. The first concerns the two-dimensional interaction between a boundary layer and a convecting vortex. The size and height above the wall of the vortex are the same order of magnitude as the boundary layer thickness. A strong primary vortex creates a secondary vortex which causes the rebound of the primary, a response observed in many previous studies. However, weaker vortices as well do not follow the inviscid trajectory despite the absence of a secondary vortex. Rather than creating vorticity at the wall, a weaker vortex mainly redistributes the vorticity of the boundary layer. The redistributed vorticity alters the path of the vortex in ways not seen for vortex/wall interactions.
Degree
thesis:*- Name thesis:degree_name
- Ph. D.
- Level thesis:degree_level
- doctoral
- Discipline thesis:degree_discipline
- Engineering Mechanics
- Department dc:contributor.department
- Engineering Mechanics
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 1996
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Luton, J. Alan
- Chair dc:contributor.committeechair
-
- Ragab, Saad A.
- Committee members dc:contributor.committeemember
-
- Telionis, Demetri P.
- Mook, Dean T.
- Nayfeh, Ali H.
- Devenport, William J.
Subjects
dc:subject × 5Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
- Language dc:language.iso
- en
Identifiers
dc:identifier.*- Dc Identifier Other
- etd-10052007-143040
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/39631