Four examples of potential flow modeled around an airfoil. On the top, the flow is without circulation (on the bottom, circulation is added artificially until the stagnation point reaches a satisfactory position). On the right, flow is reversed and displays unphysical behavior, illustrating that the reversibility of potential flow can lead to absurd cases.
<a href="//commons.wikimedia.org/wiki/User:Ariadacapo" title="User:Ariadacapo">Olivier Cleynen</a>
2015-02
<span class="int-own-work" lang="en">Own work</span>