Vortical flows over delta wings and numerical prediction of vortex breakdownNavier-Stokes solutions of subsonic vortical flow over a 75 deg sweep delta wing with a sharp leading edge are presented. The sensitivity of the solution to the numerical scheme is examined using both a partially upwind scheme and a scheme with central differencing in all directions. At moderate angles of attack, no vortex breakdown is observed, whereas the higher angle-of-attack cases exhibit breakdown. The effect of numerical grid density is investigated, and solutions that are obtained with various grid densities are compared with experimental data. An embedded grid approach is implemented to enable higher resolution in selected isolated flow regions, such as the leeward-side surface, the leading-edge vortical flow, and the vortex breakdown region.
Ekaterinaris, J. A. (U.S. Navy-NASA Joint Institute of Aeronautics Moffett Field, CA, United States)
Schiff, Lewis B. (NASA Ames Research Center Moffett Field, CA, United States)