Loading...
Please wait, while we are loading the content...
Similar Documents
Impulsive start of a symmetric airfoil at high angle of attack
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Katz, Joseph Yon, Steven Rogers, Stuart E. |
| Copyright Year | 1996 |
| Description | The fluid dynamic phenomena following the impulsive start of a NACA 0015 airfoil were studied by using a time accurate solution of the incompressible laminar Navier-Stokes equations. Angle of attack was set at 10 deg to simulate steady-state poststall conditions at a Reynolds number of 1.2 x 10(exp 4). The calculation revealed that large initial lift values can be obtained, immediately following the impulsive start, when a trapped vortex develops above the airfoil. Before the buildup of this trapped vortex and immediately after the airfoil was set into motion, the fluid is attached to the airfoil's surface and flows around the trailing edge, demonstrating the delay in the buildup of the classical Kutta condition. The transient of this effect is quite short and is followed by an attached How event that leads to the trapped vortex that has a longer duration. The just described initial phenomenon eventually transits into a fully developed separated flow pattern identifiable by an alternating, periodic vortex shedding. |
| File Size | 725252 |
| Page Count | 8 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19980021295 |
| Archival Resource Key | ark:/13960/t13n73680 |
| Language | English |
| Publisher Date | 1996-02-01 |
| Access Restriction | Open |
| Subject Keyword | Aerodynamics Navier-stokes Equation Incompressible Flow Vortex Shedding Reynolds Number Trailing Edges Airfoils Angle of Attack Separated Flow Steady State Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
