The Wind Tunnel is the col between DAFF Dome and the Cottage Dome. The routes are described in the Supertopo guide but even with the aid of the photo in that book it's hard to identify the starts.
Approach as for the South Flank of DAFF Dome but keep walking up and right to reach the col. Drop down from the trees a short way on a glacis. Most of the climbs are on the east side (Cottage Dome) of the saddle.
Mountain Project's determination of some of the classic, most popular, highest rated routes for Wind Tunnel: