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Experimental study of an inclined jet-in-cross-flow interacting with a vortex generator
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Zaman, K. B. M. Q. Heidmann, J. D. Rigby, D. L. |
| Copyright Year | 2010 |
| Description | An experiment is conducted on the effectiveness of a vortex generator (VG) in preventing lift-off of a jet-in-cross-flow (JICF), with film-cooling application in mind. The jet issues into the boundary layer at an angle of 20 to the free-stream. The effect of a triangular ramp-shaped VG is studied while varying its geometry and location. Detailed flow-field properties are documented for a specific case in which the height of the VG and the diameter of the orifice are comparable to the approach boundary layer thickness. This combination of VG and JICF produce a streamwise vortex pair with vorticity magnitude three times larger (and of opposite sense) than that found in the JICF alone. Such a VG appears to be most effective in keeping the jet attached to the wall. While most of the data are taken at a jet-to-freestream momentum flux ratio (J) of 2, limited surveys are done for varying J. The VG is found to have a significant effect even at the highest J (=11) covered in the experiment. Effect of parametric variation is studied mostly from surveys ten diameters downstream from the orifice. When the VG height is halved there is a lift-off of the jet. On the other hand, when the height is doubled, the jet core is dissipated due to larger turbulence intensities. Varying the location of the VG, over a distance of three diameters from the orifice, is found to have little impact. Rounding off the edges of the VG with increasing radius of curvature progressively diminishes the effect. However, a small radius of curvature may be quite tolerable in practice. |
| File Size | 1159631 |
| Page Count | 18 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20110016116 |
| Archival Resource Key | ark:/13960/t77t2pg1z |
| Language | English |
| Publisher Date | 2010-01-04 |
| Access Restriction | Open |
| Subject Keyword | Aerodynamics Position Location Turbulence Momentum Edges Orifices Vortices Boundary Layer Thickness Flow Distribution Vortex Generators Film Cooling Free Flow Boundary Layers Cross Flow Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
