In this paper computed results from Steamline Upwind/Petrov-Galerkin and Discontinuous Galerkin finite-element methods are compared for various two-dimensional compressible Navier-Stokes applications. Identical meshes are utilized for each comparison with linear, quadratic, and cubic elements employed. The order of accuracy is assessed for each scheme for viscous flows using the method of manufactured solutions, and results from each scheme are compared to experimental data. Each scheme is notionally of design order, and results from both compare well with experimental data. Both schemes are viable finite-element discretization techniques, and neither applies an unnecessary amount of artificial dissipation.

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An experimental study was conducted to investigate the behavior of the wing-tip vortex structures generated by a square-tipped, rectangular NACA0012 wing. A Stereoscopic Particle Image Velocimetry (SPIV) system was used to conducted detailed flow field measurements to elucidate the key features of the wing-tip vortex structures in the near field. One of the great advantages of the present SPIV measurements over the classical measurement technique is that the vortex wandering can be removed directly by tracking the center of the wingtip vortex in the instantaneous measurement frames. By tracking the center of the wingtip vortex, the wandering and turbulence in the vortex can be decoupled completely. This method was applied to investigate the effects of the angle of attack of the test wing and wind tunnel wall on the evolution of the wingtip vortex in the near field. In order to decouple the effects of vortex wandering, Devenport et al. (1996) suggested an analytical method to predict the wandering free velocity profile. The velocity profile predicted by the Devenport et al. (1996) method was compared with the SPIV re-centered velocity profile quantitatively.

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