Base for the comparison was a cup-type anemometer
next came a split 4-bladed version
lastly a revised version of the last design, only with zero overlap
(as suggested in my previosu postings, I was curious about whether any more lift effect might be gained)
Summary / interpretation of results
Well it seems my alternative designs werent a radical improvement on the original!
I'm a bit mystified by the ripple in all plots around the 17rpm (of the base anemometer, which I must get around to calibrating in mph!) mark;