Technical review: German and Hungarian Grands Prix

Posted on

| Written by

Looking back on the technical developments from Hockenheim and the Hungaroring, here’s John Beamer.

As Mark Webber said the list of accusations thrown at Red Bull is starting to look silly. First we had the trick ride height system, then illegal suspension fairings and now flexing front wings.

In the midst of all this teams were racing to copy Red Bull’s exhaust blown diffuser and next year, with the banning of double diffusers, no doubt pull-rod suspension will be flavour of the month.

The Red Bull package

2010 represents a microcosm of why, once a team has a technical advantage, it is relatively easy to keep it. While rival constructors chase their tail to try to copy and retrofit parts to their car, the team ahead is refining and optimising its aero and dreaming up the next technical leap forward. Given the regulations won’t radically change until 2013 we could be in for a period of Red Bull dominance. As Christian Horner repeatedly says its not one thing that makes the RB06 quick but the whole package.

Since the last technical review two races – Germany and Hungary – have passed and a couple of trends are clear. Red Bull is still yards ahead in raw downforce. Ferrari has usurped McLaren as the second quickest team, and Renault has also closed the gap to the Woking-based outfit. Mercedes along with many of the other teams on the grid have started to focus resources on its 2011 challenger.

The flexi-wing controversy

The pitlane scuttlebutt since Hockenheim has been about Red Bull’s (and to a less extent Ferrari’s) flexable front wing. The TV pictures are clear – under high downforce the endplates sink. There are contrasting opinions as to what is happening. Some say that the the wing is less rigid so that under high downforce conditions the tips visibly lower, which creates a ground effect under the endplate.

Yet another explanation is that Red Bull is running more rake (which means the car is inclined to the road lengthways, with the rear raised). If this was so then the back of the RB06 should be visibly higher – and although film suggests that the Red Bull is more nose down than its rivals it doesn’t appear to be running an aggressive rake.

Another is that the the front part of the floor (splitter) is somehow flexing and after Vettel’s nose dropped off in P3 at Silverstone there is suspicion that this is what Red Bull is doing. This is prohibited and the flex tests are stringent. The front splitter is subject to 200kg loadings and is only allowed to deflect 5mm. Although teams were able to circumvent this by hinging the splitter with a rear mounting and using a 200kg preloaded spring at the front (to resist the loading test) the FIA became wise to this practice in 2007 as part of the Spygate saga. In short it would be a substantial engineering feat to circumvent the rules. Even if the splitter did deflect it is likely that the underside plank would suffer more than the proscribed 1mm wear.

There was even another, more outlandish suggestion that perhaps the nose cone itself was mounted to the chassis with a spring, allowing the entire wing to operate in ground effect, but FIA checks found nothing.

Although teams are still partly in the dark about what Red Bull’s secret sauce is, the most likely explanation is that the wing is manufactured in such a way as to allow flexing under high downforce conditions. To this end after the Hungarian Grand Prix the FIA announced new deflection tests for Spa. According to article 3.17.1 the front wing is allowed to, “deflect no more that 10mm vertically when a 500N load is applied to it 800mm forward of the front wheel centre line and 795 mm from the car centre line”. The new test will double the loading and with a 20mm deflection now allowed.

This may seem a wash but it is designed to stop team building in non-linear flex whereby the wing will meet the 10mm/500N condition but then start to flex more generously at higher loadings. We’ll need to wait until Spa to see if the RB06 wing flexes as much on camera.

The advantage of flexi-wings

A flexing front-wing could be quite an advantage as it not only generates more downforce but it self-modulates so is less pitch sensitive.

Typically teams build a semi-circular channel into the footplate that is used to create and capture vortices. These help generate downforce and also seal the underside of the front wing (from being contaminated with dirty air). Under high speed the force acting on the footplate will increase, which will pull the carbon fibre down. This has two benefits: first a ground effect is created which produces more downforce and hence a larger ground effect; second the vortex inducing seal is more powerful so makes the rest of the wing work more efficiently – both are very powerful particularly through medium- and high-speed corners.

A flexing front wing also better handles stall (particularly through slow corners) as the front wing will deflect absorbing the change in load rather than transmitting the load to the suspension (which would be the case in a stiff wing car). This means the suspension can be run softer (or tyre pressures lower) for better traction in the slow corners.

Exhaust Blown Diffuser (EBD)

McLaren has slipped to third in terms of raw pace as it races to get on top of its EBD. After the Silverstone fiasco, McLaren returned to Hockenheim with a revised EBD set-up with many modifications. The most obvious were that the exhausts were moved out from under the sidepods and the cut was changed to better direct gas flow and control heat dispersion. In addition the wishbones and floor were reinforced with more heat resistant material to prevent buckling.

Also McLaren changed the shaping aft of the exhaust outlet – there is now a small inlet that allows some of the exhaust gasses to pass into the outer diffuser channel to boost downforce. Unlike the RB06 which was designed with the EBD diffuser in mind the McLaren solution feels more compromised and definitely works less efficiently.

More teams continue to bring EBD to the grid, with Force India being the latest. Similar to other teams, Force India lowered the exhausts to the floor and reprofiled the sidepods. The team ran the device simply to gather data with no real intention to race it. Expect both cars to feature EBD at Spa.

Ferrari, Renault, Williams and Mercedes continue to optimise their EBD. For Hockenheim the Scuderia’s exhaust was lower and more forward allowing the exhaust gas to act on a larger volume. Similar to McLaren the exhaust is cut at an angle and heat shielding on the floor and around the wishbones has been bolstered.

After Hungary, Renault announced that its latest EBD saw the team overcome the initial drop in engine power it experienced. This phenomenon is worth discussing in more detail. Designers make the exhaust exits from each cylinder a different length to produce a series of sequential resonant frequencies (the resonant frequency of the exhaust depends on length). These then feed into a tail pipe (two – one for each four-cylinder block) which produces a secondary resonant frequency. Correctly tuning the exhaust pipes allows engineers to better manage the pressure distribution at the exhaust outlets to evacuate the hot gasses. Failure to do this will result in reduced engine power as the exhaust is less efficient at escaping from the cylinders.

Williams and Mercedes both introduced big updates to their blown floor and started to experiment with blowing the exhausts into the diffusers rather than just above them. Williams introduced a large inlet (almost an open fronted diffuser) by the exhaust to allow the hot gasses to feed the floor. These gasses will add energy to the airflow in the outer channel increasing downforce. Mercedes had a similar solution albeit with a much restricted inlet.

Rear wings

Both Renault and Mercedes introduced significant changes to their rear wings. In preparation for the launch of its F-duct at Spa, Renault introduced a new front wing with a sharp ‘V’ cutaway in the centre and a couple of additional inlets closer to the endplate to help equalise air pressure. Similarly Mercedes added two bulbous inlets to its rear wing – the effect of this and the Renault ‘V’ are the same.

The intent is to create a virtual third rear wing element (a blown rear wing). Air enters the inlet on the upper side of the rear wing and then exits through a very thinly etched slot on the underside. This is akin to adding a flap with a very small slot gap and allows the wing to be run at a steeper angle without stall. Superficially this solution may seem illegal but careful position of the slots and the fact that the etched slot on the underside of the car doesn’t run across the entire width of the wing means that the rear wing still conforms to the ‘two closed sections’ rule.

McLaren has run a similar system for most of the season but is harder to spot with the fluorescent orange paint scheme – unlike Mercedes’ unwieldy copycat.

Front wings

All the major teams continued to tweak their front wing designs but with no major overhauls. At Hungary Ferrari wavered on whether to run its new (Silverstone edition) triple element front wing. The three element version provides more consistent performance without necessarily increasing downforce (unless the wing is run at a steeper angle, which then costs drag).

While the flex-wing controversy was going on Red Bull continued to evolve its front wing, which for Hungary sported a duct in the footplate to allow air to bleed through, which stops air from separating.

A few of the smaller teams introduced new front wings. Sauber copied the Force India/Red Bull camera mounts and now place them in between the nose pylons. This adds a little downforce to the central front section of the car where the FIA has specified the flat central wing section. Toro Rosso also introduced some updates with a revised endplate which helps direct air around the front tyre and also Red Bull style vanes under the nose to reduce turbulence under the chassis.

After the break

Although the RB06 is supreme everywhere the upcoming tracks should allow both Ferrari and McLaren to challenge so don’t expect the championship to be a foregone conclusion. McLaren’s prodigious straight line speed should be enough to keep it in contention in Spa (although it will lose time in the high downforce middle sector), while in Monza the McLaren should also shine through as pace rather than aero matters. Singapore is a twisty bumpy circuit much like Monaco where the pitch sensitive MP4/25 will likely struggle badly. The F10 should do well. Korea is an unknown and Japan, with its fast corners, should be a Red Bull flush. While McLaren will probably struggle over the bumps of Interlagos expect Red Bull and Ferrari to be strong both there and at the season finale in Abu Dhabi.

Also the technical themes in the last third of the season won’t be too different to the first two-thirds. The leading teams will continue to refine and optimise their EBDs, the flexi-wing brouhaha will continue to rumble, and all teams will continue to tinker across their cars. Also don’t be too surprised to see another tech fissure (no doubt Red Bull linked) to break before the end of the season. Watch this space.

F1 technology

Browse all F1 technology articles

46 comments on “Technical review: German and Hungarian Grands Prix”

  1. I’m not so sure that it will be a forgone conlcusion that McLaren will do well at Monza. Yes they have great top speed, but a huge amount of the time which is up for grabs at Monza is to be found in the chicanes, and the (very) stiffly spung McLaren may struggle. I’m expecting an Alonso win at Monza and McLaren to be more competitive around Spa.

    At this stage I find it hard to think of anyone other than Vettel or Webber walking away with the WDC.

    1. Yes, I don’t think McLaren will be that strong at Monza, I think Alonso winning is the most likely (Although as an Alonso fan I would say that) and also possibly a good placing for Barrichello.

      1. Barrichello? Not that I doubt you, but why him?

        1. He has a good history at Monza, a selection of his best results are;
          5th (x2)
          4th (x2)
          3rd (x1)
          2nd (x1)
          1st (x3)

    2. I think Vettel and Webber have the best shot at the championship currently, but I don’t expect either one of the to “walk away with the WDC.” It will be a hard fought battle to the last race most likely.

    3. “a huge amount of the time which is up for grabs at Monza is to be found in the chicanes, and the (very) stiffly spung McLaren may struggle”

      So how did they manage a 1-2 at Canada with the chicanes there? They’ll be going for the win at Monza. And maybe at Spa and Abu Dhabi.

      1. Read chicanes as “kerbs”. The kerbs at Monza are far more severe than those at Montreal. The mistakes that happen when you post at 11pm.

        “They’ll be going for the win at Monza. And maybe at Spa and Abu Dhabi.”

        Well tyhey are a racing team with a shot at both the WDC and WCC, so I imagine they would want to win everywhere…

  2. Excellent article, thank you. The implication is that McLaren, Ferrari, and Red Bull are the only ones who need to focus on 2010. All others can start their 2011 cars and try to catch up.

  3. Hi everyone,
    I’ve used F1Fanatic for ages, and just recently became a member. Can anyone help explain to me how to have a picture as my avatar?

    Thanks,
    daykind

      1. Thanks for that,

        As you can now see, I have a gravatar!

        Great help

        1. You’re welcome :)

        2. Also may I congratulate you on your excelent choice of avatar :P

          1. Thankyou very much! Yours is great too!

      2. Thanks for the steps. I kept meaning to but am also lazy.

  4. I now think Ferrari will win the next 2 races, Mclaren gone so Webber will have my support out of RBR and Ferrari

  5. Hi John, a small doubt.

    The flexi-wing moves upwards in the slower corners thus causing it to stall and reduce the load on the suspension. But doesn’t the same flexi-wing cause excessive load to the suspension in high-speed corners when it drops down and transfers higher amount of load to the suspension (as opposed to the fixed-wing cars). This would make it tougher for the teams to run a softer suspension as you propose, isn’t it?

    Secondly, regarding your personal opinion, since you describe that it would be a ‘substantial engineering feat’ to circumvent the FIA rules – which the Red Bull and Ferrari are certainly doing – are you in favor of the flexi-wings as they are innovative feats of engineering or you would want them banned?

    The way I see it is FIA seems to be on a witch-hunt against Red Bull and Ferrari. The 4 cars have clearly passed all the FIA tests and now FIA changes its own rules? What can this be if not a desperate attempt by FIA to prove that Red Bull and Ferrari wings are illegal?

    1. Overall the force on the suspension should be slightly higher than for the fixed wing cars, but thats purely because the flexiwings produce more downforce. The positioning of the wing should not affect the suspension in ways other than through weight (negligable) and downforce.

      I don’t see how the FIA are on a witchhunt though, they’re not changing the rules. The rules say it shouldn’t flex, and that the tests can be changed if there is reasonable cause for it. They may partially do it because they’re trying to keep the championship close (viewer ratings and all that) but since the flexing is visible from camera views it is understandable that they want to find out why. The wings may be totally legal but they may have just found a way round the testing. It is their jobs to find out.

      1. As you state Skett, the rules are, that wings should not flex. And these obviously do (like we had in 2007 with Flex wings).
        The FIA would look pretty stupid if they did not act on it (use the provision for changing the tests), after being put into bad light for not being able to prevent this with the current tests in the first place.

  6. The wings are illegal, they just can’t prove it with a static test

  7. HounslowBusGarage
    17th August 2010, 20:55

    Excellent analytical article as always, John.
    I think I begin to understand . . .
    But can you (or anyone else) point me towards a simple explanation of the difference between pull and push-rod suspension systems? An explanation with lots of pictures and little words, preferably.
    On the Maclaren, you say they made the rear floor of more heat-resistnat materials. But how far back does the plank have to extend – could the FIA effectivey outlaw EBDs by extending the plank backwards?

    1. Here’s a pretty good example comparing the two:
      http://www.maserati-alfieri.co.uk/maser/chubasco-10.gif

      As you can see on the left, the push rod will compress the shock via the large(ish) linkage on top when the suspension compresses. On the right, the pull rod will compress the shock by pushing the small(ish) linkage at the bottom of the shock when the suspension compresses and pulls on the rod. The four bar linkage that allows the suspension to move is relatively the same on either.

      1. Aha!
        Scales fall from my eyes. Thanks US Peter.

        1. My pleasure. Here are a couple good shots of the RB6 rear suspension. You can clearly see the pull rod going from the rear wheel downward towards the rear of the car where it enters low.
          http://www.auto123.com/ArtImages/118971/red-bull-inline.jpg
          http://i837.photobucket.com/albums/zz299/n_anirudh/rb6nakedaylgturk.jpg

          The front suspension on the RB6 appears to be a conventional push rod.
          http://www.autoevolution.com/images/news/fia-not-investigating-red-bull-s-suspension-18688_1.jpg

      2. And the advantages of pull-rod vs push-rod are:
        1. weight saving, the rod can be slimmer and therefore lighter – rods are stronger in tension than compression, this may also give a marginal aerodynamic advantage
        2. lower centre of gravity – the spring and damper are generally positioned horizontally in an F1 car and so the whole unit can be put almost in line with the floor of the car rather the somewhere near the top of the wheel, this can also be used to lower the roll centre which is generally a good thing too

        the disadvantages are:
        1. rods are stronger in tension than compression – because the rod is under tension it can be slimmer, this means that it will buckle more easily under compression – which is not normally the case, until the car is raised off its wheels, then the weight of the wheel puts the rod under compression, generally pull-rods are designed to be strong enough to take the weight of the wheel and not much more because that will make it plenty strong enough under tension, because of the compulsory pit stops I imagine RBRs pull-rods are slightly stronger than that
        2. packaging – as RBR experienced last year, they didnt have as much room for the diffuser, this year they’ve managed to design around that
        3. maintenance – much easier to adjust/replace something that sits on the top of the car than underneath it

  8. Thank you John. Interesting to read about the drop in Renault power with the exhaust frequencies… you learn something new every day I guess $:)

  9. Great article, thanks!

    Interesting stuff about the exhaust frequencies as mentioned above.

    I’m very curious as to how this wing for RBR works..hmm!

  10. Very, very interesting stuff; I love knowing now that exhaust systems are tuned to produce particular frequencies – too cool. In future, if I may put forward a suggestion for all of us technical and engineering ignorants, more and bigger photos or drawings illustrating the finer points would be the icing on the cake for your articles.

  11. As Always wonderful analysis,and the exhaust frequencies discussed,this reminds me of how one engineer used to work out power outputs by taping the engine note of each competitor,then working out the frequencies by a given revoloution,very clever and i,m sure teams still practice this,no independent bench test of each engine has been carried out since development was frozen,yet Red Bull are convinced the Renault engine is down by around 20/30 bhp.
    How the gases escape from any exhaust is fundamental to a vehicles performance,the less restriction from the manifold the better.

  12. I always thought the exhaust from each cylinder should be exactly the same length before the collector (where they join each other). If they have unequal lengths then at certain revs (i.e. exhaust gas speed) the gas pulse from one cylinder (with a shorter length) will block* the previous pulse from another cylinder (with a longer length) because the gases end up reaching the collector at the same time.

    Where the exhaust length tuning comes in is primarily in the measurement from manifold face to the collector. This is where it all gets very mathematical (of which I have very poor knowledge), but very basically the shorter the length the more power you get at higher revs (so you get a peakier power band higher up the revs), the longer the length the more power you get with lower revs (which tends to reduce your peak power but gives a flatter power curve). I’m not sure if the length of exhaust after the join has as significant an effect.

    There’s a similar tuning possibility with the air intake as well, the length of the intake dictates where in the rev band you get most power (hence why some clever engines have a variable length intake to try and give more power over a wider range). Intake length and exhuast length should be tuned together.

    For each join in the exhaust then the length between each join is significant, but all pipes between each join should be the same as each other. I believe current F1 engines all have just one join (4 into 1), but it is common in performance engines to have 2 joins (4 into 2 into 1).

    * When I say block, what really happens is that as the gases move through the exhaust they are in discrete pulses, as all the gas pulses are moving in the same direction this actually creates a low pressure pocket between each pulse – if the lengths are all equal then as each pocket reaches the collector then the lower pressure helps “pull” the pulse from a neighbouring cylinder into the collector, hence the gas pulses actually help each other escape faster, this has the effect of reducing back pressure on the engine and therefore removes more gas from the cylinder for each cycle (the cylinder is never completely void) which allows the engine to turn more freely which releases more power.

    If, however, the gases reach the collector at the same time then they have to merge and hence are slowed down, which causes more back pressure, which means less gas escapes the cylinder which reduces power. This is why equal length exhaust pipes are actually very important.

    Apologies for the geek waffle… I hope I made some sense.

    1. Wouldn’t the exhaust pipes before the joint be different in lenght anyway, but tuned to have those pulses arrive in the right order?

      But nice comment on how it works.

      1. They try as hard as possible to keep them the same length to maximise the scavenging affect. If they were different lengths, the pulses would reach the join in different times dependent on the engine speed, so sometimes they would match and sometimes they wouldn’t. It’s not easy, see these pics of (admittedly slightly older) F1 engines…

        http://www.rbracing-rsr.com/turbo/mergeferrari1.jpg

        http://www.rbracing-rsr.com/turbo/exhaustF1.jpg (I think this one is the 2005 championship winning engine)

        You can see the pipes go through some pretty crazy contortions to try and get equal length.

        And here’s another explanation of it all I just found, I think a bit better than mine… http://www.superchevy.com/technical/engines_drivetrain/exhaust/0504sc_header/index.html

        1. Accidental Mick
          19th August 2010, 8:09

          Thanks for that – very interesting.

  13. John:
    any comments on Pat Fry’s changes to the F10?

  14. Great work John! I am very curious about the RBR wings in Spa and weather we will ever learn how they are doing this.
    So McLaren and Ferrari are working hard to make up speed on Red Bull, getting their tricks to work, while RBR focusses on ever new finds. It makes for a great 3 way battle, with suprises at every race.

    Mercedes must be working full out to find some tricks and loopholes for next year, they can not have another lacklustre year with their resources and with Renault getting back to the top. A 5 way battle next year would be amazing.

    Oh, i minded small error in the part about rear wings (… Renault introduced a new front wing with a sharp ‘V’ cutaway in the centre), not being picky, just to avoid confusion.

  15. Excellent article John!

    Very insightful. However, inititally ( watching the video footage ) I thought the RB6’s front wing is flexing just to reduce AoA at high speed and hence the drag. From the pics of the car at high speed it is most likely that front wing is used to manage the flow under the sidepods taking into the consideration pitch RB6 is riding at.
    These three elements combined together yield in excellent performance. Oh I almost forgot, the third element is allowing the car to lean in the corners without sacrificing traction – very special rollbars I think… Maybe, that’s another tech fissure from Red Bull Technology. hwo knows…

  16. Well with this info: Looking at ‘spy’ comparison shots by rival team.@speed RBR frnt wing cntre 75mm,Ferrari 72mm off ground.Merc 94mm and McLarn 97mm.
    And i read somewhere that 1mm closer to ground can give overall 0.1s advantage its not a wonder that RBR is that fast.

  17. It’s plain unfair to change the front wing tests half way through a season!

    1. How so? The tests are not the rules (even though laid out it in them).

      Flexing on purpose is breaking the rules, the tests are just there to approve that you aren’t breaking them.

      1. If this is the case then the tests are useless. They should never put a maximum deflection at ‘X’ amount of stress. They should stress them and allow a very tiny deflection before complete failure.
        This would stop all flexing on all parts and you’d never have to alter the tests.

  18. A while ago the BBC showed various views of the McLaren with the EBD, which must be similar to the Red Bulls, Ferrari, Mercedes etc, and I was surprised to see how much aero work was done underneath the engine and wing.
    Surely the rules state that the underside of the cars must be flat, since any channelling of airflow beneath the car is seen as part of a ‘ground-effect’ package? Or is this another case of all the teams managing to stay within the rules without actually doing so?

  19. Younger Hamilton
    18th August 2010, 16:53

    This is not a Technical Review,Its so biased!!!!

  20. Younger Hamilton
    18th August 2010, 18:19

    Im Sorry but im just irritated and angry to see Ferrari there instead of McLaren with Red Bull.Great article John Really appreciate what you’re doing you’re teaching me a lot about the gains Red Bull have and the others are having.Hopefully McLaren catch back up to the frontrunners asap

  21. Direct injection and ABS are inventions that had its origins in F1 and, nowadays, are used in road cars. This technical review shows that something is very wrong about F1 because it is all about aerodynamics. I think the F1 suits better now to companies like Boeing/Airbus/Bombardier/Embraer/Cesnna than Mercedes/Ferrari/Renault.

  22. Fantastic stuff John. You help us non-engineers understand this stuff. I look forward to your next technical analysis.

  23. I hate to be an ignorant stick in the mud, but I haven’t been convinced that any front wings are flexing and the whole thing is a tempest in a tea pot. The front wing is fixed to the chassis. When an aero load is applied to the wing it will compress the shocks and springs forcing the nose of the chassis, and the wing, lower to the ground. Unless you’re running a solid, immovable suspension (but then you’d be racing a go-cart). Relative to the tires and suspension components the wing absolutely must drop some amount. http://scarbsf1.wordpress.com/ has a animated (and edited) clip that purports to show the front wing flexing. If you’ll notice, the suspension arm angles change as well which, in my opinion, is the reason the wing appears to lower relative to the tires. Another effect that no one mentions is that the degree of stiffness of the front suspension will contribute to how much the nose will lower under loading. Perhaps Red Bull has just managed to find more front down force….

    The supposedly “blown” diffuser is another hype. Big deal, the exhaust velocity is completely insignificant compared to the speed of the vehicle so there is no “thrust” involved, so the only benefit I can see is that the exhaust is extremely hot and less dense than the surrounding air which should give some minor pressure differential to work with.

    If I’m wrong, prove it. I think it’s all BS like most of the twizzles and tweaks on the cars that don’t seem to make any difference at all when they get scraped off. Psych job!

Comments are closed.