Venting rear wheel fairings at Toyota

Wheel fairings have become fairly normal by now, and most teams have identical designs. At the rear, every team used a fixed shield with a central opening, both allowing the mechanics to fit the tyres and to provide an exhaust for brake air (and dust).
Toyota have now given a new twist to it as they designed a venting shield. Instead of a closed carbon disc, the element consists of small, identical aerofoils that allow hot air to escape from the wheel. More specifically at the upper half of the wheel, the rotational speed and the airspeed around the wheel will cause brake air to be drawn away, effectively increasing the cooling capacity.
A similar shape can often be recognised in the arms of road car wheels, although these mostly direct air into the wheel, rather than out of it.