CANARD TIP VORTEX SPLITTING IN A CANARD-WING CONFIGURATION - EXPERIMENTAL-OBSERVATIONS

In previous works the aerodynamic behavior of canard configurations was studied, both experimentally (by measuring forces1 and pressure distributions2) and numerically.3-4 For a correct numerical simulation a suitable representation of the vortex wake is necessary, as to both its position and intensity distribution. No important differences between experiments and numerical predictions arise when the canard wake does not strongly interfere with the wing surface (see, e.g., Ref. 4), but the results are not as good when this interference is strong. In this situation, a suitable numerical representation requires a deeper knowledge of the physical behavior of the canard vortex wake. This is especially true when it directly impinges on the wing, near its leading edge; in fact, in these conditions, the behavior of the vorticity field has not yet been clarified. In previous investigations3, 4 it has been shown that computational potential models may, for specific configurations, predict a splitting of the fore surface tip vortex into two parts: 1) passing over and 2) below the rear surface; recently, the possibility of this phenomenon has also been found by applying a Navier-Stokes solver to a close-coupled canard-wing configuration.5. © 1995 American Institute of Aeronautics and Astronautics, Inc., All rights reserved.