The influence of flap-end geometry modifications on the near-field wake behind a generic high-lift wing/flap configuration is investigated experimentally with a single-tube yawmeter. It is found that flap-end additions tend to split the concentrated area of streamwise vorticity shed by the flap into two less intense regions, associated with the tips of the flap and the addition. For shorter additions, these regions tend to roll up together, resulting in a slightly more diffuse flap vortex of almost unchanged circulation. For larger additions, the outer region is captured by the tip vortex, which correspondingly gains in circulation at the expense of the flap vortex. In all cases, the vorticity centroid of the rolled-up wake is shifted outboard, and the overall circulation slightly increased. However, the associated lift increase implies a decrease in overall circulation at a given lift coefficient.
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