Aerodynamic Impact of Vortex Generators on a Relaxed-Compression Low-Boom Inlet

Sie sind hier: Homepage > Suche

Aerodynamic Impact of Vortex Generators on a Relaxed-Compression Low-Boom Inlet

Rybalko, Michael / Loth, Eric

The application of subsonic and supersonic vortex generators for flow control in an external compression, axisymmetric low-boom concept inlet was investigated experimentally and computationally. The low-boom inlet design is conceptually based on a previous scale model tested in the NASA $1 \times 1 ft$ supersonic wind tunnel. It features a zero-angle cowl and relaxed isentropic compression centerbody spike, resulting in defocused oblique shocks and a weak terminating normal shock. A design of experiments computational methodology was used to select device size and location to determine the optimal choice of device geometry and placement, with the objective of reducing radial flow distortion for on-design conditions. The resulting test matrix of vortex generator geometry and placement was specified for model inlet testing conducted at the $8 \times 6 ft$ supersonic wind tunnel at NASA Glenn Research Center in the Fall of 2010. Comparisons of Reynolds-averaged Navier–Stokes predictions with experimental data were subsequently performed, including stagnation pressure profiles at the aerodynamic interface plane, axisymmetric incompressible boundary-layer shape factors and radial flow distortion indices, and surface pressure along the inlet centerbody. The vortex generator performance trends are consistent between the predictions and experimental results and the supersonic vortex generators demonstrated that flow separation near the throat could be reduced, whereas the subsonic vortex generators demonstrated that the incompressible shape factor near the aerodynamic interface plane can be substantially reduced.