Computational Treatment of Three-Dimensional Transonic Canard-Wing Interactions

The transonic canard-wing interaction problem is simulated using the modified small disturbance transonic theory. The wing and the canard are treated in a sheared fine grid system that is embedded in a global Cartesian crude grid. An appropriate far field and asymptotic expression for the velocity potential derived using Green's theorem is implemented. Results are presented for a few canard-wing configurations and compared with available experimental data. The weakening of the wing shock due to the presence of the canard downwash is illustrated in terms of contour plots. An empirical incidence correction for the wing leading-edge vortex gives good agreement with experiment at low incidences. For higher angles of attack, the results indicate that a more sophisticated vortex roll-up and induction model is required.