2017-2020 Aerodynamic Regulations Thread

[Sevach]

Looking at the car comparison thread I see that the cars are neatly clustered around 3500 mm wheelbase. Does it seem likely that this will change with the proposed aero changes? Will the bigger diffuser encourage more or less rake which might in turn lead to longer or shorter wheelbase to keep the relationship between splitter, front wing and the ground similar to today?

I would think a bigger diffuser would lead to less rake, but even this new one might not be big enough to force "flat" cars.

I have no idea what direction teams will follow with these new wider cars, it should allow very creative packaging of radiators(even fuel tank), a lot of untapped floor real state, i don't know if that will mean shorter or even longer wheelbases.
Also the rear wing being moved down, might force teams to reconsider their hot air exits (now more or less standard for all cars).

[henry]

Having seen the law of consequences at work in Melbourne qualifying caused me to think about one of the consequences of the proposed 2017 rules.

If the rules were to reduce Melbourne lap times by, say, 3 seconds I don't think it would make much difference to qualifying, other than they will go quicker, but in the race I suspect that the 100kg restriction will be thrown into sharp focus.

The cars will have more drag because of increased frontal area and higher drag coefficient and the higher average lap speed will increase fuel useage rate roughly on a cube law. So if the lap times are 3 seconds faster that's 10% higher fuel use for 3% less time. If they currently use all they will need to save 7% fuel somewhere and I'm guessing it will be at the end of the straights. So lower top speeds and more lift and coast.

In my mind the probability is that the lead teams will increase downforce as much as possible to be fast through the corners and ruin the aero of following cars. Top speed won't matter because no one will get close enough to challenge.

A possibility is that when the teams get into the simulators for real they'll find that at some tracks they can't go a full race distance on 100 kg and the FIA will reduce the race distances.

I believe these changes are being brought in to improve something. Can't for the life of me see what.

[michl420]

Just one quick note for thinking. Looks like the 2016 cars are around 1,5 sec faster then 2015. Why does Pirelli (and others) make such a big riot for another maybe 2 or 3 sec? No charge to anyone, just a note.

[godlameroso]

I agree, from the looks of it, those changes are useless, the current formula is still young, the cars still have plenty of scope for development, both engine and chassis wise. Making changes seems forced, in a year of developing to the current regulations we could have race speeds similar to 2013.

[Juzh]

I agree, from the looks of it, those changes are useless

In your opinion.

3 years is not young in my book. How much time do you need? 10 years? 20?

[jure]

Having seen the law of consequences at work in Melbourne qualifying caused me to think about one of the consequences of the proposed 2017 rules.

The cars will have more drag because of increased frontal area and higher drag coefficient and the higher average lap speed will increase fuel useage rate roughly on a cube law. So if the lap times are 3 seconds faster that's 10% higher fuel use for 3% less time. If they currently use all they will need to save 7% fuel somewhere and I'm guessing it will be at the end of the straights. So lower top speeds and more lift and coast.

It's not just drag. There will be less braking and less acceleration which will save fuel.

[henry]

Having seen the law of consequences at work in Melbourne qualifying caused me to think about one of the consequences of the proposed 2017 rules.

The cars will have more drag because of increased frontal area and higher drag coefficient and the higher average lap speed will increase fuel useage rate roughly on a cube law. So if the lap times are 3 seconds faster that's 10% higher fuel use for 3% less time. If they currently use all they will need to save 7% fuel somewhere and I'm guessing it will be at the end of the straights. So lower top speeds and more lift and coast.

It's not just drag. There will be less braking and less acceleration which will save fuel.

Can you explain that please?

My thought is that if you take a short scenario of medium speed corner onto a straight.

They'll carry more speed through the corner, more aero drag and more tyre drag.

They'll be into full traction earlier because higher downforce and higher exit speed and they'll brake later, more aero drag, higher downforce, more tyre grip, and coming off the brakes at a higher speed for the next corner. So they will be accelerating over a longer distance.

You remind me that these cars will be heavier which also have a negative effect on fuel consumption.

[Fulcrum]

Just when we start entering a period of relative competitiveness, converging evolution, and diminishing returns, another change?

Leave it alone for another year please.

[bhall II]

It's not just drag. There will be less braking and less acceleration which will save fuel.

Can you explain that please?

My thought is that if you take a short scenario of medium speed corner onto a straight.

They'll carry more speed through the corner, more aero drag and more tyre drag.

[...]

This is correct. Anything that increases time spent at higher speeds will reduce efficiency, because drag squares with speed. Combine larger frontal area, increased induced drag, increased rolling resistance (wider front tires), and increased minimum weight, but with the same fuel allocation given to current cars for which such factors are all lower, and you'll see yet another rule change that doesn't quite make sense.

I'm all for enhanced aero and the quicker cars it will enable, but it's gotta be done right, and this ain't it.

Something needs to be done, though. The fundamental mechanics of the current formula have been in play since 2009, and we are well into the range of diminishing returns - just watch how in-season development changes very little.

[henry]

It's not just drag. There will be less braking and less acceleration which will save fuel.

Can you explain that please?

My thought is that if you take a short scenario of medium speed corner onto a straight.

They'll carry more speed through the corner, more aero drag and more tyre drag.

[...]

This is correct. Anything that increases time spent at higher speeds will reduce efficiency, because drag squares with speed. Combine larger frontal area, increased induced drag, increased rolling resistance (wider front tires), and increased minimum weight, but with the same fuel allocation given to current cars for which such factors are all lower, and you'll see yet another rule change that doesn't quite make sense.

I'm all for enhanced aero and the quicker cars it will enable, but it's gotta be done right, and this ain't it.

Something needs to be done, though. The fundamental mechanics of the current formula have been in play since 2009, and we are well into the range of diminishing returns - just watch how in-season development changes very little.

The 2017 regs have been published and the teams will be into the first stages of their designs. I expect they will have run simulations and will know how performance will be "enhanced" in qualy and race mode. The team principles probably already have ballpark numbers about speed and quite likely the effect on fuel use. They might well know how much sense the regs make. But just as with the laughable qualification changes they'll not want to rock the boat. At some point the sense will hit the fan. When it does we can expect a flurry of last minute changes around fuel usage probably ending in shorter races.

I think we disagree on the need for enhanced speed. I think the sport would be better if we had faster-down-the-straights slower-round-corner nimble little rockets rather than the stuck-to-the-ground limousines we have now.

But I don't think that would be popular with the S-class driving, Hackett wearing, Rolex regarding, Krug imbibing patrons the spectacle is designed for.

[bhall II]

I think straight-line speed is too easy for everyone involved; cornering speed is not easy for anyone involved; and downforce in general does not keep cars planted to the track...





A brief aside directed toward no one in particular: it cracks me up that the same fans who routinely celebrate the supreme skill of F1 drivers, and who often call for the sport to revolve around the drivers, nonetheless never seem to consider the notion that supreme skill is precisely why the cars appear to run on rails. Instead, those fans typically claim downforce makes the cars easier to drive.

Downforce is performance potential, nothing more.

In any case, teams are aware of the possibility that fuel-related problems may arise in 2017 and are working toward a solution...

When asked by Motorsport.com what would happen if the 100kg limit stayed, {Renault's Nick] Chester said: "I think it will be a mess.

"At the [recent] tech regulations meeting, we voted to get rid of the race fuel limit.

"We still have the flow limit, so you have a green message that the cars cannot consume too much, but abolishing the fuel limit will get rid of lift and coast and having to manage fuel, which seems like a good thing for racing.

"If we stay at 100kg and go to the 2017 regulations then there will be a lot of fuel saving, and I think people will start complaining about it."

[henry]

...

In any case, teams are aware of the possibility that fuel-related problems may arise in 2017 and are working toward a solution...

When asked by Motorsport.com what would happen if the 100kg limit stayed, Chester said: "I think it will be a mess.

"At the [recent] tech regulations meeting, we voted to get rid of the race fuel limit.

"We still have the flow limit, so you have a green message that the cars cannot consume too much, but abolishing the fuel limit will get rid of lift and coast and having to manage fuel, which seems like a good thing for racing.

"If we stay at 100kg and go to the 2017 regulations then there will be a lot of fuel saving, and I think people will start complaining about it."

Thanks. I hadn't seen that.

I would be all in favour of getting rid of the 100 kg limit.

If they were to get rid of the 100kg limit I think it would change more than lift and coast. I expect they would burn fuel to charge the ES when traction limited and improve race lap times moving them closer to qualification speed.

[bhall II]

I'm very much in favor of scrapping the fuel limit. But, given their obvious interdependence, a sane person might still wonder why the fuel issue wasn't settled at the same time as the aero rules.

[henry]

I'm very much in favor of scrapping the fuel limit. But, given their obvious interdependence, a sane person might still wonder why the fuel issue wasn't settled at the same time as the aero rules.

To be charitable perhaps it's because the fuel capacity limit is in the sporting regs not the technical regs.

[bhall II]

That's actually not unreasonable.