Location: Covilhã, Portugal (and sometimes in Évora)
Post
Those white things in front of the radiator/sidepod intake. Main ideas: deflect part of the airflow around the car and remove part of the airflow from under the car and into the radiator/sidepod inlet. Also it smoothens some of the turbulence that comes from the front suspension.
Turning vanes as they were introduced are air guidance carbon plates that are attached to the monocoque and mainly placed in between the front wheels (that means you will be unable to see the largest part of the vanes when you look from the side of the car).
The big parts that are in front of the sidepod are called barge boards. You can see these at Williams, Ferrari, McLaren, Minardi (and possible some others).
Both are meant to do the same though: guiding air that comes from between the front wheels to help sidepod air intake and smooth airflow around the sidepod.
I also looked at the f1.com site - it seems quite clear to me that the turning vanes project horizontally from the bottom of the radiator intake (on the sidepod) towards the front of the car. Renault joined the turning vane to the bargeboard (the vertical bit) to strengthen it. My question is: what has it got to do with turning?