Intuitively I would have thought that at the 15 R.P.M or so of a large rotor ,most of the wind would whistle straight through the swept area without giving up the maximum power available. It would seem that more blades would give higher torque and thereby increase power output for a given rotor size. Why are they made this way,as the old wild west wind pumps had many blades ,surely they would have experimented with this and found the configuration which worked best without the benefit? of computer models.
