I really like this kind of testing in "reality" and not only computer simulation.
How much the drag would be rising up by using the vortex idea ?
The word vortex make my thinking that also there must be a disadvantage using this technologie.
I think the drag of a blade, going in to stall, of course must be high and we prevent the blade from
going to fast into stall. On the other hand we rise up the drag in "normal" operation of the blade, where
also a "non vortex blade" wouldn't be go into stall.
If i remember well you made a test under nearly the same wind condtions with and without the
bremakles and you noticed more loading power using them.
Grüsse
Bernd