2 ms·
Huh. Seen in retrospect, it's sort of obvious. Propeller efficiency can be increased by mounting them in pairs, one behind the other, where the two are rotating
by marvin 6y ago
Huh. Seen in retrospect, it's sort of obvious. Propeller efficiency can be increased by mounting them in pairs, one behind the other, where the two are rotating in different directions. This reduces the "twisting" movement of the airflow behind the propeller, which is a sign of energy that's lost and not used for propulsion.
Stands to reason that the same thing would be the case with wind turbines, and maybe a little surprising that it hasn't been on anyone's radar before now.
- mannykannot 6y agoThe way this effect works, however, is dependent on a Coriolis-force-induced veer in the atmospheric boundary layer, something that is not an issue in contra-rotating propellers. Unless one understands the mechanism, one will be unaware that, for any given location, it matters which way the first turbine rotates. At best, an arrangement based on an analogy to contra-rotating propellers would be a lucky guess, right for the wrong reasons.