Flow Around a Rankine Half-Body

    The vector field that described the flow of a fluid around a Rankine half-body is given by
        Overscript[v, ⇀] = U (1 + h/(2π) x/(x^2 + y^2), h/(2π) y/(x^2 + y^2)), defined outside the Rankine half-body.
We obtain the following system of differential equations for the streamlines
        x ' (t) = U (1 + h/(2π) x(t)/(x^2(t) + y^2(t))),
        y ' (t) = (U h)/(2π) y(t)/(x^2(t) + y^2(t)).

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