Lift or Downforce, it's exactly the same thing.
Just depends whether you label Z negative or positive. I'm used to dealing with aircraft aerodynamics, not race car, so I'm sorry if I use the words interchangeably.
It's not really the chord that's of concern. It's more the alpha (angle of attack/incidence), when you have a movable or sprung section, under high speed load it will move back. This reduces alpha, reduces lift and thus when you resolve the vector you get less induced drag. It doesn't even need to be sprung or pivoted really, if it's flexible enough it will twist by it's own accord along the spanwise axis. This has the same effect. But this is all related to the actual wing sections, this is what Ferrari got into trouble about last season in one of the races. It's not related to guide control like the part in discussion.
It is these issues that the FIA have a problem with regarding movable aerodynamics. As I said early on, and also mentioned by other people, nothing is solid on a race car. Everything flexes under load, so it's just up to the FIA to determine whether a team is doing enough to ensure their aerodynamics are rigid. They have a set of deformation against load rules. If it was against the rules the FIA would easily pick it up.
Alberto - seriously what rules are you reading? Certainly not the FIA ones. There is nothing in the FIA rules about laminar or turbulent flow. Anyway I strongly disagree. The guide when moving with elastics like that will create a vortex flow. This itself will probably create more drag and turbulent flow than if it was solid. The guide is more likely to better place air into the engine intakes, move the air around the driveshaft and linkages better etc.
The type of drag you are talking about is profile drag, not induced drag. The purpose of moveable aerodynamics as I said above it to reduce induced drag. Induced drag is where the force created by the wing is taken perpendicular to the alpha angle, which isn't straight down the Z axis, as there needs to be a given alpha to generate force. Therefore when you resolve the vector you get your lift but also an induced drag component, the induced drag. This section of the front wing isn't producing a lift force by the looks of it, therefore it moving won't affect induced drag, as there isn't any induced drag to start with, only profile drag.
Having this device move in airflow gives no advantage that I can see compared to being rigid. Therefore it's not breaking any rules whatsoever pro diving its movement is in the FIA tolerances, and we can't exactly measure movement off the youtube video. And once again, who knows if it's even being used, the video was from a test session was it not? It might not ever be used at a race.
So summarise my points:
- It's not a traditional device that would be moved during aerodynamics (normally wing sections)
- The movement is aero-elastic rather than hinged or pivoted
- I can not see any advantages of it moving rather than being solid
- It doesn't appear to break any FIA rules
Without seeing any test data, or looking at the real thing or a tunnel model it's impossible to tell exactly. And everyone else would be the same. So who knows really.
And oops, I just realised how much I typed.
