Sorry Greg, "no induced drag in a wind tunnel" is simply not true.
Once again, you don't understand.
If you put a 3-D wing in a wind tunnel, you will get induced drag.
The article you posted even documents the effect:
----------snip--------------
This drag occurs because the flow near the wing tips is distorted
spanwise as a result of the pressure difference from the top to the
bottom of the wing. Swirling vortices are formed at the wing tips, and
there is an energy associated with these vortices.
----------snip--------------
See that? Flow "near the wing tips is distorted"....vortices are
formed at the wing tips
2-D flow is achieved when the wing tips are flush against the sides of
the wind tunnel. No wing tips = no pressure leaking around the wing
tips = no wingtip vortices = no induced drag.
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