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Roughness induced transition in a supersonic boundary layer
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Balakumar, Ponnampalam Kergerise, Michael A. |
| Copyright Year | 2013 |
| Description | Direct numerical simulation is used to investigate the transition induced by threedimensional isolated roughness elements in a supersonic boundary layer at a free stream Mach number of 3.5. Simulations are performed for two different configurations: one is a square planform roughness and the other is a diamond planform roughness. The mean-flow calculations show that the roughness induces counter rotating streamwise vortices downstream of the roughness. These vortices persist for a long distance downstream and lift the low momentum fluid from the near wall region and place it near the outer part of the boundary layer. This forms highly inflectional boundary layer profiles. These observations agree with recent experimental observations. The receptivity calculations showed that the amplitudes of the mass-flux fluctuations near the neutral point for the diamond shape roughness are the same as the amplitude of the acoustic disturbances. They are three times smaller for the square shape roughness. |
| File Size | 945062 |
| Page Count | 18 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20140000468 |
| Archival Resource Key | ark:/13960/t5w71g292 |
| Language | English |
| Publisher Date | 2013-06-24 |
| Access Restriction | Open |
| Subject Keyword | Fluid Mechanics And Thermodynamics Direct Numerical Simulation Three Dimensional Flow Vortices Boundary Layer Transition Surface Roughness Shapes Free Flow Supersonic Boundary Layers Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
