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Thread: F1 car vs LMP1 car - downforce levels

  1. #61
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    ^ That I buy. Those points make a lot of sense. He pointed out the gain from clearing the flow to enhance the "beam wing"(lower element on the rear wing structure) function, which works in helping diffuser drawing flow out. And he pointed out that the pullrod with its location will compromise the diffuser itself, but probably the other gain made will negate that.

    Edit, I posted later than Matra, I am referring to the post from Scrutineer which shed more light into the autosport issue.
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  2. #62
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    Formula 1? - The Official F1? Website

    Might help explain the tech

    oooo, missed this snippet last race
    http://www.autoevolution.com/news/re...ing-19035.html
    Last edited by Matra et Alpine; 04-21-2010 at 11:14 AM.
    "A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'

  3. #63
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    That formula1.com link continues to show how much F1 teams runs mechanically backward geometry for aero gain. They run their lower balljoint so high up that in most places will likely avoid that kind of layout because it would compromise camber compliance and wheel installation stiffness....but if it means a bigger diffuser its worth it....

    Same trend I guess has been used for years on the front too with the raise nose and zero keel...
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  4. #64
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    Remember they don't run stock rose joints nor components.
    So tolerance and expansion/compression modulus is way outside the range of materials availabel to you and most of the "how to" papers
    I think you're using standard material models present in all the off-the-shelf analysis suites.
    But, yes , in general. As perfection in all areas is always impossible then the designers are making the real-world compromises and by being "smart" what looks like a compromise brings surprises in other areas that other designers may struggle to comprehend. ( eg the Tyrrel di-hedral high nose configuration had NOTHING to do with the noes, the front or the aero per se. They designed the nose that way to deliver a DIFFERENT benefit that other teams didnt' realise for months )
    "A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'

  5. #65
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    While the material used is obviously far and away from what us mere mortal can obtain, apple to apple, if all else being the same, some basics of structural mechanics applies to all objects. So wider the base of a structure, the more stiffness you can get from it. I forgot where I read it, but the starting point for ideal kinematic design starts with the largest ball-joint seperation and toe-base you can package in the wheel and work inward...something obviously has little bearing now in an aero driven design.
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  6. #66
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    RM I completely agree ... except it's not related to real world as in the real world you only need ENOUGH stiffness, ENOUGH control, ENOUGH movement.
    So you can do that with larger and wider OR you can do it with better materials.
    If you reach the same end goal then the one that carries a performacne benefit in F1 will win out as money is still being thrown at design ideas.
    I'd also add, that as aero is so critical then any F1 designer is going to start THERE -- thus why we've had transverse gearboxes developed and this year gearboxes lifted and the uptake of old slanted drivetrain. These are things you would NOT design UNLESS the aero and CG was more important than the mechanical purity.
    It's a different world with differnet factors.
    Other auto designers typically have price first and packaging second. F1 are a rule to themselves

    Not sure how long you've followed F1, but the ultimate aero-over-commonsense was the BT54 and the slanted BMW engine
    "A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'

  7. #67
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    Quote Originally Posted by TheScrutineer View Post
    Interesting. I read an article a few years ago in F1Racing magazine were Williams attempted design and predict the performance of a fantasy F1 car. I believe it was 2004. They used the same 3 litre V10 as the then current car, and changed the regs to allow ground affect, slick tyres and unlimited wheels. The car ended up having six wheels (4 at rear) and an indycar style front wing and very low rear wing. I believe the car was capable of up to 14g though the corners, therefore un driveable without a modified G-suit!
    do you have that article to share?

    I found scans of the article but it was in the french version of the magazine and I don't speak french. The numbers I saw on the french version doesn't mention this 14gs, where did you get those from?

    Thanks for your attention, anyway!

  8. #68
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    Quote Originally Posted by RacingManiac View Post
    That formula1.com link continues to show how much F1 teams runs mechanically backward geometry for aero gain. They run their lower balljoint so high up that in most places will likely avoid that kind of layout because it would compromise camber compliance and wheel installation stiffness....but if it means a bigger diffuser its worth it....

    Same trend I guess has been used for years on the front too with the raise nose and zero keel...
    This seems to be an F1 thing ever since the 1980s or so. All classes to some extent or another simply represent the best interpretation of the current rules and technology of the time. Personally I think the high step noses on F1 cars look terrible. However, they make sense on F1 cars due to the rules that make non-underbody aero so critical. Indy cars never went to step noses because with their rules they never made sense (both from safety and aero points of view).

    What I hate to see is all the spec junior classes copying F1 looks as if the F1 engineers were somehow expressing the best school of thought on race car design. No, in this case they only express the best schools of thought with respect to their rules. Few junior classes and no spec classes have any justifiable reason to use a high step nose given the penalties such designs take in both chassis strength and suspension geometry.

    The FSAE team I worked with a bit seemed to love the idea of a stepped nose but at least they were doing it because they though it made their front suspension geometry better. Given the geometry they chose it may not have been a bad choice but it wasn't a great geometry.

    It's a pity F1 rule makers haven't found a good way to shift the design emphasis back to mechanical vs aero grip. I think the cars and the racing might be better for it.

  9. #69
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    Quote Originally Posted by culver View Post
    It's a pity F1 rule makers haven't found a good way to shift the design emphasis back to mechanical vs aero grip. I think the cars and the racing might be better for it.
    F1's high performance is heavily reliant on aerodynamics. You can always cut downforce to put emphasis on mechanical grip, but you can never cut it out if you want the championship to be the fastest circuit racers.
    "This car is about as refined as a Glaswegian dock worker after 10 cans of special brew"

  10. #70
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    BTW, returning to the off-topic discussion we had on the Autosport piece(which is now posted on the website, if you have subscription you can read that), having read the whole thing now I can summarize its content somewhat:

    -Other teams claim RBR runs a ride-height system, RBR denies.

    -RBR is fast in race trim, but much faster in quali trim

    -Mark Hughes believes RBR based on some of the design cue of the car.

    -Pull rod allows for cleaner upper body packaging which benefits airflow to the rear wing/beam wing, thus making them more effective.

    -Pull rod packaging compromises diffuser design, limiting RBR to go with less extreme diffuser shape and size(compare to Renault, McLaren...etc).

    -Upper body aero(ie, wings) is not influenced by ride height, underbody is. Thus the advantage gained from cleaner pullrod package allows for more upper body downforce. Modern F1 car does not run true ground effect, thus upper body downforce accounts for greater percentage of total downforce.

    -lower ride height gained from ride height system benefits under body aero.

    -complicated diffuser employed by rival teams stand to lose more when run in higher ride height, where as RBR's simpler design does not(comparatively).

    -Thus on balance, RBR can maintain the performance better even without ride height system. Thus explaining their quali advantage(as contributed through their pull rod design).



    Interesting points I must say, and logical, given how fast 2009's RB5 was even when Brawn was dominating with the DDD in the beginning of 2009. While front wing is working somewhat with the ground effect(thus influenced by ride height), the combination that the fuel mass is likely affecting the rear ride height more than the front, and that the front has adjustable flaps, may just negate that.
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  11. #71
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    Quote Originally Posted by RacingManiac View Post
    -Other teams claim RBR runs a ride-height system, RBR denies.
    Now not at HP so don't have acces to state-of-art CAD .. BUT would be worth looking at the high mount point for the lower arm.

    IF the suspension geometry alters in a way that the engine power will fight against it and then provide the energy to lever it upwards woudl be intriguing.

    Wonder if others are thinking this way.

    eg, if you alter the toe-in, then on power being applied the traction will introduce a force trying to straighten the wheels up. With the right suspension design if that force is then translated into another vector direction it coudl possibly act as a lever and thus provide less "push" ?
    Or in a simlar way as the tyres wear ?
    Coudl make for larger challenge for driver and loss of some power, but if that is returned via improved aero then it coudl be the dogs-bollocks !

    AND woudl explain why RBR have this unusual "wrong" suspension design

    at this point in my engineering mind, I want to either model it or build it ....... damn !!!!
    "A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'

  12. #72
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    Quote Originally Posted by TheScrutineer View Post
    F1's high performance is heavily reliant on aerodynamics. You can always cut downforce to put emphasis on mechanical grip, but you can never cut it out if you want the championship to be the fastest circuit racers.
    I'm well aware of that. However with a different set of rules it would be possible to go just as fast with less total downforce by using what you have more efficiently.

  13. #73
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    Would be hard to get round the corners any faster with less downforce
    Top speed is moot anyway as fast straights are no use with slow corners, so teams optimise the trade-off.
    "A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'

  14. #74
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    I think people misunderstand. With a different set of rules you could keep the total grip about the same but you would set it up in such a way that it was less favorable to what amount to very screwy geometry because you need to do everything to get aero to work.

    Believe me, I understand why F1 engineers have chosen to maximize aero at all cost. Part of why F1 cars have chosen this rout is because of the tire rules. Those tiny 13" wheels have resulted in very large section tires. In recent times (not sure about this year) about 75% of the car's "suspension" travel was the deflection of the tires. In most race cars only about 50% or so of the total deflection would be in the tires. Because so much of the deflection is in the tires the particulars of the suspension geometry become less important. If you were to change to smaller section tires I suspect you would find the engineers would be more interested in improving suspension geometry to regain mechanical grip. It's all a trade off but remember that mechanical grip and downforce work together. If you improve mechanical grip by 5% in general you improve your grip at all speeds by ~5%. Right now the rules have simply made it more favorable to get that marginal increase in downforce rather than the marginal increase in mechanical grip. With a change in the rules that balance would change. Now if they would let them put the front wings further forward and give them some more underbody aero so we could get rid of the ever uglier stepped noses that would be great.

  15. #75
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    Sorry for the history lesson(s) , but in the days of F1 on high profile tyres the industry did not have the technology to produce tyres capable of the stresses of todays.
    Nor was damper/spring capability anywhere near current, not to mention DESIGNERS

    "Mechanical grip" can't be created once you've learned how to keep a tyre flat on the ground.
    Weight determines the contact patch and to get more "mecahnical grip" you'll need to increase WEIGHT.

    OR .... use aero to create downforce to mimi weight increase.

    You can't "move" compliance around and expect it to work the same.
    A tyre wall is the only part capable of small deflection to maximise the grip.
    Tryign to move that back into a suspension part has added LOTS more mass to move to get the desired effect and by the time it's responded the bump is past. BIG risk of "porpoising" with those kind of delayed reaction.

    WHere do you think we woudl see a 5% improvement in MECHANICAL grip and rememvber aero grip increases with speed, so at high speed the "grip" is much MUCH higher than mechanical on it's own can ever achieve.

    You can't possibly put front wings further forward as the "unintended consequence" of that woudl be now space in corners and everyone hitting each other as the nose now swings through a larger arc on turning.

    Lost stepped nose and you go back to pre-Tyrrel innovation with MASSIVE side pods that eat up LOTS of power just pushing them through the air.

    "more" underbody aero has the risk of causing major issues when it releases -- NASCAR flips anyone ? If most of the downforce only came from the underbody then we'd see the kind of incidents back in the skirts days.
    "A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'

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