= Solution
Take positive <circulation> to mean counterclockwise in the $(x,z)$ diagram, with $x$ right and $z$ up. The upper surface is then traversed right to left. To first order in $a/b$,
$$
\boxed{\Gamma=\oint\mathbf u\cdot d\mathbf l
=\int_{-b/2}^{b/2}(U_0-u_s)\,dx=-2U_0a.}
$$
Thus the bound <circulation> is clockwise. Any exterior contour enclosing the <hydrofoil> has the same <circulation> in an <irrotational flow>; a globally completed two-dimensional flow must contain a circulation component decaying as $|\Gamma|/(2\pi r)$ at large distance. The simple local upper/lower velocity prescription cannot describe the entire exterior. For a start from rest, <Kelvin's circulation theorem> requires compensating shed <vorticity>, represented by a starting vortex in a physical wake.
Numerically,
$$
\boxed{\Gamma=-0.40\ \mathrm{m^2\,s^{-1}},\qquad
L'_{\rm dynamic}=8.0\times10^2\ \mathrm{N\,m^{-1}}.}
$$
If the question's fluid <force> includes <buoyancy>, $B'\simeq1.25\times10^3\ \mathrm{N\,m^{-1}}$ and the total upward fluid <force> is about $2.05\times10^3\ \mathrm{N\,m^{-1}}$, using $g=9.81\ \mathrm{m\,s^{-2}}$. Weight of the <hydrofoil> is not specified and is not part of this fluid <force>. The motion-induced <lift> also agrees with the <Kutta–Joukowski theorem>, $L'=-\rho U_0\Gamma$ in this orientation.
The chord-based <Reynolds number> is
$$
\boxed{\mathrm{Re}=\frac{U_0b}{\nu}\simeq2.7\times10^6.}
$$
At this large <Reynolds number>, smooth <laminar flow> over the whole body is unlikely in ordinary conditions; wall layers may undergo transition and separate. A thin-layer <inviscid flow> approximation outside them can remain useful, but does not justify globally <laminar flow>.
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