A variational formulation of the adjoint Kutta condition in potential flow

Carlos Lozano; Jorge Ponsin

doi:10.1016/j.aml.2026.110027

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arXiv · 2606.06937

A variational formulation of the adjoint Kutta condition in potential flow

Carlos Lozano·Jorge Ponsin

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Abstract

We give a variational formulation of the continuous adjoint Kutta condition for two-dimensional subcritical potential flow, with emphasis on the Kutta condition and the role of the wake. We show that the adjoint Kutta condition can be imposed by a penalty term evaluated at the trailing edge, with the corresponding Lagrange multiplier determined by stationarity of the Lagrangian with respect to circulation, and that a wake treatment is not required. Some of the implications of these results for adjoint consistency are also briefly discussed.

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Carlos Lozano, Jorge Ponsin. 2026-06-05. A variational formulation of the adjoint Kutta condition in potential flow. https://doi.org/10.1016/j.aml.2026.110027

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