Rear Wing Design

[lordzylos]

I don't know how many of you watch the WRC, but the rear wing on most of the cars have vertical elements in the middle. What does this do to the air going over and through the wing and how does it help? Also, how come no teams in F1 use this design? Is it not permited in the rules?

Here is a picture of the Subaru wing.

[seymour]

Its just speculation on my part, since I really don't know anything about the sport, but don't rally cars have to be stock cars? I don't mean stock in the American definition of stock car racing which means absolutely nothing. I mean stock in that the car is actually a production vehicle?

Perhaps the vertical elements distribute the downforce load more evenly over the body which is not really designed to handle such loads?

Okay, I don't really believe that either.

My real guess is that it has to do with the crazy yaw angles rally cars experience while turning. The rear wing efficiency is dramatically reduced when the car is moving sideways as much as it is moving forward. The vertical elements probably help move flow straight over the wing in addition to counteracting any yaw angle of the vehicle with respect to the vehicles velocity vector.

Considering the much lower yaw angles in F1, it seems it would not offer near the benefit. However, I believe Williams ran a dorsal fin last year which would have similar effect, and the fin atop the Renault that everyone is complaining about being so ugly is probably there for similar effect.

Given Renault's obvious prowess in the windtunnel and the unlikelihood that Renault's engineers arbitrarily decided to beat their car with an ugly stick, I won't be surprised to see other teams testing and racing similar fins.

[NickT]

F1 and WRC have conciderably different requirements. F1 needs effiecent down force within a significantly higher speed range say 70 to 200 mph. The WRC cars generally work in a much slower speed range, say 40 to 110 mph, they are more concerned about generating significant and usable downforce whiilest travelling sideways not so concerned about effiency as they spend very little time near the cars maximum speed

[scarbs]

except that BAR have now adopted them




Link to my other reports on the recent F1 test Silverstone

http://www.scarbsf1.com/silv_test0204/BAR_test0204.htm
http://www.scarbsf1.com/silv_test0204/MAC_test0204.htm
http://www.scarbsf1.com/silv_test0204/J ... st0204.htm

[Scuderia_Russ]

Great reports Scarbs,some cracking pics! Thanks for sharing.

[Carbon]

Thanks for the great tech reports Scarbs, how do you manage to get in the tests, and take the photos?

[Irvingthien]

Since the FIA has banned the third element which is on the frontal and upper side of the wing for 2004, where does the teams gets the rearend downforce which was used to be generated bt the third element?

[Steven]

Well 2 elements compared to 3 in the rear wing is a theoretical loss of about 6% downforce from the rear wing, if nothing else would change.

However, Renault stated their currect car already has more downforce than last year's contender. This higher efficiency car be reached by better flipups, winglets, but for the rear wing, just enable a better airflow to it. That is actually quite much what they did, wonderfully sleek sidepods and most likely some gains concerning airflow aroud the driver's helmet

PS: woohooo my 500th post

[NickT]

Well done Tomba excellent web site , keep it coming

Scarbs, once again we find you have your finger right there on the pulse of F1 Thanks for sharing all your good work with the rest of us F1 Technical junkies

[pyry]

the reason why the rally cars have vertical elements is because of the sideward movement, it helps to steady the rear end, because it creates air resistance when the car is moving sideways. dunno if someone already answered that, didnt bother to read the other answers