Aerodynamic trends in 2011 discussion

[raymondu999]

Hey all. So far we've seen several recurring trends, just thought we should have a thread to discuss these. First off we see the high nose is quite widespread now, as is the wide platypus-duckbeak crossbreed that Sauber and Mercedes (at least in their 3d render) has.

Next, one I'm quite curios about is the squared off sidepod inlets. a la MP4-25. Ferrari and Sauber have shown this so far, Any theories as to the benefits of this shape? Merc and Lotus seem to have gone the more traditional "triangular shape" route though.

Also, the v-nose. Back when it was introduced the benefits were that they could do a similar v-shape on the underside of the body so more air would flow in on the underside. But with the maximum height of the nose regs, wouldn't having a v-nose force the central section to dip lower and restrict air instead?

Also, what's the benefit of non-undercutted sidepods? Many of the cars produced have had no undercut there and i'm quite confused.

Packaging seems to be the buzzword so far Is it time to compare the released cars to the Red Bull 5/6 cars yet?

Thanks!!

[godlameroso]

It's going to be a tricky balancing act this year, will teams keep pushing for front end downforce, doing whatever they can to balance out the rear? Perhaps the high noses shift the CoG rearward while maintaining the desired weight distribution. Perhaps this is done to balance the higher frontal downforce in relation to the rear of the car. In addition, the higher nose allows more air to flow to that part of the car, if that area is designed to condition or manipulate air, then more area equals more effect. What I'm saying is that it's a design compromise, to a certain extent they are trying to get the nose to generate some downforce as well.

On the other side, I see teams trying to turn both surfaces of the diffuser to their advantage, the developments seem to show teams have clawed back some of the rear downforce, and have had to make compromises in their designs to balance the aero of the car. I believe that some of the design convergence is due to the mandated weight distribution, if this was not in place we would see more...adventurous designs.

[Twaddle]

I wanted to start some discussion on a post marcush made in the STR6 thread, but thought it was a bit OT for there and fitted quite well in here.

"Still I ask myself if the steeply falling sidepods we see everywhere are really the optimum.. on their own they will definitively produce lift ..."

I'd kind of always assumed that this was the case, but I'm starting to have my doubts. The reason being that they're not on their own, they're connected to the floor. While the sidepod profile suggests that they would act like a lift producing aerofoil, the fact that the floor then extends the profile in a roughly horizontal direction (actually slightly rising due to rake). We also know that there is a large upward accelleration of the air leaving the floor at the rear of the car (the trailing edge of the sidepod and floor combination), this makes all the difference. The sidepod and floor combination isn't actually acting to accellerate the air leaving the trailing edge downwards and therefore we don't have a corresponding reaction upwards on the floor and sidepod.

The Newtonian view gives us the net effect, but I'm not sure it contradicts the idea of a localised low pressure area above the sidepods that would influence the aero balance of the car. The whole thing is starting to give me a headache.

[marcush.]

hehe ....I make you think? would not have believed I had any influence here..

I understand your thought but to me the airfoil looks like 400mm high at the leading edge and only 175(50 stepplane plus 125 difusser height) drawing a line through the front radius and the trailing edge the profile is directed downwards and will not produce much downforce if any.In the context of the beamwing I have to admit that suddenly the whole arrangement looks almost like a slot gap 2 element wing and I´m not so sure if this whole thing could not produce downforce....

[Richard]

Not all noses are high.... well one of them isn't!

McLaren have gone for the air over the top approach while all the others go for the current convention of under the nose and round the side.

from viewtopic.php?p=226319#p226319

[raymondu999]

Yes, over 2010 and 2011 McLaren do seem to be going for a "straight through, little obstruction" approach. They did that with trying the sidepods sloping downwards in 2010, and the flat nose, and now they've taken it up a notch with those hideous moosepods. Ironically it seems kind of like they're playing safe, and "we don't know what the air will do around undercuts, flowing around sidepods with a tight arse, so let's just let it flow straight on to the beam wing."

They seem to be going for another low-drag car this year again, no? Then they can just ratchet up the wing. As opposite to the Red Bull's philosophy of grip grip grip, then we'll reduce the wing if we need to cover any people.

[Twaddle]

hehe ....I make you think? would not have believed I had any influence here..

I understand your thought but to me the airfoil looks like 400mm high at the leading edge and only 175(50 stepplane plus 125 difusser height) drawing a line through the front radius and the trailing edge the profile is directed downwards and will not produce much downforce if any.In the context of the beamwing I have to admit that suddenly the whole arrangement looks almost like a slot gap 2 element wing and I´m not so sure if this whole thing could not produce downforce....

Assuming you're talking about the STR6 here, I think what I said above doesn't apply directly since the sidepod is completely undercut rather than connected directly to the floor. I was really talking about steeply sloping sidepods in general (hence moving the discussion to here), I should have been clearer on that. I think that the proximity of the floor may mean that it will still intercept any downward flowing air that gets that low before joining the upwash out the back of the car (halting the downward movement obviously meaning accelleration in the upward direction), though.

I was going to expand on the case of the STR6 , as the underside of the sidepod seems to be shaped to create a venturi effect in conjunction with the floor, reducing pressure under the sidepod and negating any drop in pressure above the pod. We're really interested in the pressure differential between the top of the pod and the under side of the floor though, and I ran into headache territory again trying to figure out how it all ties together.

[raymondu999]

I find it interesting that a lot of teams have converged on many elements of their cars, but some have gone for a Red Bull/Ferrari type pair of turning vanes under the nose, and some have gone for a snowplough. What exactly are the benefits of each, does anyone know? How come we don't see both at once? Is there something that doesn't work by putting both together?