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Flow-tagging velocimetry for hypersonic flows using fluorescence of nitric oxide (Document No: 20100011337)
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Fox, Jodie S. O'Byrne, Sean Smith, Daniel R. Danehy, Paul M. Houwing, A. Frank P. |
| Copyright Year | 2003 |
| Description | We demonstrate a new variation of molecular-tagging velocimetry for hypersonic flows based on laser-induced fluorescence. A thin line of nitric-oxide molecules is excited with a laser beam and then, after a time delay, a fluorescence image of the displaced line is acquired. One component of velocity is determined from the time of flight. This method is applied to measure the velocity profile in a Mach 8.5 laminar, hypersonic boundary layer in the Australian National University s T2 free-piston shock tunnel. The single-shot velocity measurement uncertainty in the freestream was found to be 3.5%, based on 90% confidence. The method is also demonstrated in the separated flow region forward of a blunt fin attached to a flat plate in a Mach 7.4 flow produced by the Australian National University s T3 free-piston shock tunnel. The measurement uncertainty in the blunt fin experiment is approximately 30%, owing mainly to low fluorescence intensities, which could be improved significantly in future experiments. This velocimetry method is applicable to very high-speed flows that have low collisional quenching of the fluorescing species. It is particularly convenient in facilities where planar laser-induced fluorescence is already being performed. |
| File Size | 593777 |
| Page Count | 9 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20100011337 |
| Archival Resource Key | ark:/13960/t4bp51p24 |
| Language | English |
| Publisher Date | 2003-02-01 |
| Access Restriction | Open |
| Subject Keyword | Fluid Mechanics And Thermodynamics Flat Plates Laser Induced Fluorescence Fluorescence Hypersonic Flow Fins Marking Velocity Distribution Time Lag Nitric Oxide Free Flow Hypersonic Boundary Layer Separated Flow Shock Tunnels Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
