This work couples the two enabling technologies of wake-integral drag prediction and Vorticity Confinement (VC) for the improved prediction of drag from an Euler CFD simulation. Induced drag computations of a thin wing are shown to be more accurate than the more common method of surface pressure integration when compared to Prandtl lifting-line theory. Furthermore, the Vorticity Confinement method is shown to improve trailing vortex preservation and counteract the shift from induced to entropy drag as the distance with which the vortex convects downstream of
the wing increases.
The desired application of this work is drag prediction, most notably induced drag, for aerodynamic design. High-fidelity Euler CFD simulations are desirable as they provide the most complete inviscid flow field solution. However, accurate induced drag prediction via the surface integration of pressure is generally intractable barring a sufficiently refined surface grid and resultant increase in computational load. Furthermore, the alternative wake-integral technique for drag prediction suffers from numerical dissipation. VC is shown to control the numerical dissipation with very modest computational overhead.
VC is implemented in both a two-dimensional finite-volume Euler code written by the author as well as the commercial cfd code ANSYS FLUENT. The two-dimensional research code is used to test specific formulations of the VC body force terms and illustrate the computational efficiency of the method compared to a 'brute force' reduction in spatial step size. For a three-dimensional wing simulation, ANSYS FLUENT is employed with the VC body force terms added to the solver with user-defined functions (UDFs).