Far-Field Induced Drag Prediction Using Vorticity Confinement Technique

The goal of this study is to show the efficiency of the wake-integral technique coupled with vorticity confinement method for the prediction of induced drag by inviscid numerical modeling. While the vorticity confinement method has previously been used to capture trailing vortices, its quantitative effect on improving wake-integral drag predictions has not been investigated. In the present study, parameters of vorticity confinement are tuned and the advantages of using a variable confinement parameter are demonstrated. A combination of vorticity confinement with the wake-integral technique indicates that the computational fluid dynamics-predicted induced drag for wing with and without winglet becomes insensitive to wake-integration plane location, the computed drag approaches its theoretical lifting-line value, and the spurious entropy drag is suppressed.

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