Questions about the best downforce/aero solutions in relation to pitch/flips/blowovers on an LMP car regardless of rules

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F1_LMP1
F1_LMP1
0
Joined: 21 Jul 2016, 20:27

Questions about the best downforce/aero solutions in relation to pitch/flips/blowovers on an LMP car regardless of rules

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Hi all, I was discussing this subject with a friend and I was told this was the place to go to get technical answers. I have a few questions for those in the know. We started off talking about what would be the best aero solution if there were no rules on a LMP type of car that would keep the car firmly plated on the ground, even going over crests, or hitting dips, being in dirty air, anything like that.

1) It started after watching the videos of the MB CLR, Porsche GT1, and BMW LMR flips some 15 plus years ago. And how this to my knowledge hasn't happened again since? I know those cars had very flat bottoms with small diffusers that didn't start to the rear axle line. After looking at pics of the past few years LMP1 cars it seems like they now have tunnels that seem to start much further forward, like mid car? Was this the solution to stop cars from flying? If so, why do they seem to start in the middle of the car? Is that due to the rules? It would seem if they started by the front axle line that they would be even more effective? Like if a LMP car had tunnels that started say, around the front axle area, I don't see how without some kind of failure, or accident one of these cars could possibly lift off with the huge amount of downforce that it would give the front area of the car, correct?

So with that being said, if there were no rules, what would be the ultimate solution (without resorting to strange side skirts) to the under side of these cars to give the most usable downforce, and make it so dirty air, crests, dips, etc wouldn't effect the cars at all? Tunnels from the front axle line all the way back, or is starting at the middle of the car better?

2) What other aero tricks if there were no rules would be good to add to this as well? I came up with two ideas and would like to hear your thoughts on if they would work, or if you have better solutions.

A front wing that could be under the front of the car, in front of the axle line to really keep the nose firmly planted on the ground. Then have the air after it passes by the wing either get ducted out air vents behind the front tires, or even continue on if my idea of having the tunnels start by the front axle line was a better solution.

My second idea would be a sort of auto DRS system on the rear wing. Nothing huge, just a few degrees or so. One that may automatically open on straights after it senses WOT for a second or two along with a certain steering angle, and closes when the driver hits the breaks. I figure this has a two part advantage. It would pull a little downforce off the rear of the car making the nose of the car stay well planted, and would also have less drag, giving the car more speed down the long straights.

Any input on the subject would be great.

Thanks -

bhall II
bhall II
477
Joined: 19 Jun 2014, 20:15

Re: Questions about the best downforce/aero solutions in relation to pitch/flips/blowovers on an LMP car regardless of r

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F1_LMP1 wrote:1) It started after watching the videos of the MB CLR, Porsche GT1, and BMW LMR flips some 15 plus years ago. And how this to my knowledge hasn't happened again since? I know those cars had very flat bottoms with small diffusers that didn't start to the rear axle line. After looking at pics of the past few years LMP1 cars it seems like they now have tunnels that seem to start much further forward, like mid car? Was this the solution to stop cars from flying? If so, why do they seem to start in the middle of the car? Is that due to the rules? It would seem if they started by the front axle line that they would be even more effective? Like if a LMP car had tunnels that started say, around the front axle area, I don't see how without some kind of failure, or accident one of these cars could possibly lift off with the huge amount of downforce that it would give the front area of the car, correct?
I'm not exactly sure what you mean above. Elaborate?
2) What other aero tricks if there were no rules would be good to add to this as well? I came up with two ideas and would like to hear your thoughts on if they would work, or if you have better solutions.

A front wing that could be under the front of the car, in front of the axle line to really keep the nose firmly planted on the ground. Then have the air after it passes by the wing either get ducted out air vents behind the front tires, or even continue on if my idea of having the tunnels start by the front axle line was a better solution.
Image
My second idea would be a sort of auto DRS system on the rear wing. Nothing huge, just a few degrees or so. One that may automatically open on straights after it senses WOT for a second or two along with a certain steering angle, and closes when the driver hits the breaks. I figure this has a two part advantage. It would pull a little downforce off the rear of the car making the nose of the car stay well planted, and would also have less drag, giving the car more speed down the long straights.
Note: because the low-pressure wake created by the rear wing helps extract underbody air flow from the diffuser, reducing its AoA would also reduce underbody efficiency along the entire length of the floor. That's great for reducing drag, but the front end will not maintain normal downforce.

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via Mulsanne's Corner (worth the read)