What differentiates high/low speed downforce?

[newbie]

i didnt really follow the discussion before this post, but going back to the original question as to what differentiates LS and HS downforce:

LS downforce is determined by the SCL produced by the car when at front and rear ride heights typical of a LS corner. what exactly these ride heights are will vary from car to car but typically the front wing will be high off the ground and the rake of the car will not be significant.

A HS corner will be characterised with the front wing and the diffuser both closer to ground (as the car will be pressed down onto the track by the higher load at this higher speed). because of relative suspension stiffness, the front end moves closer to the ground then the rear and so rake may be increased relative to the LS case.

in reality, an F1 team will define LS, HS and straight-line downforce by many different selected ride heights and asses the cars performance at these ride heights through both wind tunnel and CFD usage. because you only need one wind tunnel model to evaluate performance at different ride heights (and many different CAD models to do the same process in CFD), the wind tunnel is much better suited to evaluating low-speed and high-speed downforce than CFD is.

[DaveKillens]

Hey all. Just a question here. I've heard many people say that at high speed, "aero takes over." Is this because at low speed there's just a negligible amount of aero grip anyways? Also, wouldn't the grip not just be aero vs mechanical, but more of mechanical x aero grip? As in, more mechanical grip would also benefit them in the high speed, more aero would also benefit them in the low speed, to an extent? Finally, say that the car had 0 lift, 0 downforce. But it had a HUGE amount of mechanical grip (comparable to what they have nowadays in aero and mechanical grip. Would that mean that they would be able to take the high speed corners with the same speeds, or do they REALLY need aero grip for that? (Barring issues such as the car toppling over of course)

Theoretically, with just mechanical grip, the tires can generate only up to 100% of the mass. Thus, you can only get 1 G under mechanical grip. In truth, tire engineers have managed to go slightly over 1 G because the tires adhere to the small irregularities of the road surface.

But when you add wings and other aero tidbits, we can see 4 G's.


edit... thanks newbie, that info makes a lot of sense.

[Ogami musashi]

i didnt really follow the discussion before this post, but going back to the original question as to what differentiates LS and HS downforce:

LS downforce is determined by the SCL produced by the car when at front and rear ride heights typical of a LS corner. what exactly these ride heights are will vary from car to car but typically the front wing will be high off the ground and the rake of the car will not be significant.

A HS corner will be characterised with the front wing and the diffuser both closer to ground (as the car will be pressed down onto the track by the higher load at this higher speed). because of relative suspension stiffness, the front end moves closer to the ground then the rear and so rake may be increased relative to the LS case.

in reality, an F1 team will define LS, HS and straight-line downforce by many different selected ride heights and asses the cars performance at these ride heights through both wind tunnel and CFD usage. because you only need one wind tunnel model to evaluate performance at different ride heights (and many different CAD models to do the same process in CFD), the wind tunnel is much better suited to evaluating low-speed and high-speed downforce than CFD is.

Thank you; This goes well with what i said.