The nature of upgrades - efficiency vs downforce increase

[raymondu999]

Hey all. I remember reading a Ross Brawn interview a while back, and he was talking about an upcoming upgrade as being efficiency based rather than increased downforce. And it also occurred to me last year that Force India's VJM-02 was a killer on the straights with efficiency, but had dismal downforce. Then I was thinking again, couldn't the Force India with it's low-drag car, just make a wing with a greater angle of attack, and just sacrifice some of their efficiency for downforce? Can anyone help to clarify me on this issue? Thanks.

Sorry, aero is DEFINITELY not my main subject

[marcush.]

Hey all. I remember reading a Ross Brawn interview a while back, and he was talking about an upcoming upgrade as being efficiency based rather than increased downforce. And it also occurred to me last year that Force India's VJM-02 was a killer on the straights with efficiency, but had dismal downforce. Then I was thinking again, couldn't the Force India with it's low-drag car, just make a wing with a greater angle of attack, and just sacrifice some of their efficiency for downforce? Can anyone help to clarify me on this issue? Thanks.

Sorry, aero is DEFINITELY not my main subject

this is something that strikes me as well .
the game is always efficiency in my view.
But look at it that way: If you have no scope of increasing the angle of attack ,because of separation (so you´d need to put a gurney on to reattach the flow reducing efficiency)if you do so or leaving the envelope of allowed flap height when increasing the angle of attack ,you will have to go back to the drawing board and look somewhere else for downforce e.g.:increase wing area or change wing profile for more downforce. Both will of course reduce efficiency.

also the nature of the cars main hull /sidepod design has an influence on downforce..the downward slope of the sidepods surely is NOT producing DF is lift generating in itself.So it is surely good for reducing drag and allowing to exploit Rear wing and especially beamwing and difusser driving ,but this is a tradeoff with generating downforce with the sidepod generating lift .

also you can see that allmost all teams look like having increased crosssection area from2009 to this year...this should increase drag shouldn´t it? but if that is allowing you to make things easier for the flow it could pan out as a net gain in effieciency..

[raymondu999]

But if you say that... Force India was pretty much the king of efficiency in 2009 and they didn't amount to much by the year's end...

[newbie]

disagree about that ross brawn comment. if a new part brings an increase in downforce that comes with an increase in drag then it is compared to the lift v drag slope of the rear wing...i.e. if the rear wing could be cranked up to give the same increase in lift for a smaller increase in drag than this hypothetical part then this new part will probably not be kept.

[adam2007]

Teams want to create downforce with minimum drag

You cant have downforce without drag

[DaveKillens]

Teams want to create downforce with minimum drag

You cant have downforce without drag

Yup, that's what it is all about.

Generally, you can consider the efficiency of the aero package as downforce versus drag. For example, let's pick a random number, 500 kilos of downforce with a drag of 50 kilos. But if you can get the same downforce with 25 kilos of drag, then obviously you are more efficient.

You need downforce, but you also want minimal drag. Ferrari have a very efficient aero package. But maybe another team, with less resources, build a car that can generate as much downforce as the Ferrari, but has more drag, it's going to be slower than the Ferrari down the straights, and the engine has to work harder in the corners.

If you just slap on another wing to increase downforce, you aren't reducing drag, in fact you are increasing it. The car may go like stink in a slower corner, but will suffer a major speed disadvantage on the straights.

So when we hear about a team introducing an upgrade, it may not even generate more downforce, but instead maintains the same level of downforce, but with lower drag.

[riff_raff]

Besides evaluating aero mods purely in terms of L/D at some fixed condition, one must also consider sensitivity to changes in pitch and yaw. An aero device that is stable under changes in pitch and yaw is probably most desirable.

There's no free lunch in aero design. It's all about the best compromise.

[marcush.]

Besides evaluating aero mods purely in terms of L/D at some fixed condition, one must also consider sensitivity to changes in pitch and yaw. An aero device that is stable under changes in pitch and yaw is probably most desirable.

There's no free lunch in aero design. It's all about the best compromise.

of course it is .I see good aero as a means of letting air go where it wants to go
and make the most use of it on its way past your body .

You could as well put a wedge with crude front and rear wings on the grid and achieve the downforce levels we see on the top cars ,but at a severe drag penalty.
I guess the real art starts with the tradeoff in increasing licked surface with all those apendages and at the same time not increasing drag ... so effectively the parts help more to avoid unwanted airflow characteristics than they increase drag by
being there ..