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Virgin Racing’s secret: Behind the scenes at Wirth Research
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Virgin Racing’s secret: Behind the scenes at Wirth Research
Posted By: James Allen  |  05 Mar 2010   |  7:47 am GMT  |  134 comments

Of the new teams in Formula 1 it looks as though the radical Virgin Racing car is probably going to be the fastest, once it hits its stride, but preparations for the season have been undermined somewhat by reliability problems in testing.

The car has been unable to hold on to its hydraulic fluid and during its first test a front wing fell off. This has been a little embarrassing for technical director Nick Wirth, who has staked his reputation on a car which has never been anywhere near a wind tunnel, but instead was designed only using CFD or Computational Fluid Dynamics, a highly sophisticated 3D computer system.

Yesterday I went to the headquarters of Wirth Research to find out more about the reliability problems and to look more closely at whether Wirth’s plan of doing a CFD-only car will work.


Wirth is someone who sees and does things slightly differently. There are many photos on the wall, but they are of The Who and Oasis, rather than racing cars.

The whole Virgin team is operating out of Wirth’s premises on an industrial estate in Bicester at the moment. The race team will shift to the Manor team base in Sheffield after the Chinese Grand Prix, but for now the cars are being built up at Wirth, which makes sense with the tight turnarounds before the first race.

Currently spread across six buildings, Wirth Research also needs more space and in the enforced summer F1 shutdown period will be moving to a new base where all departments can be under one roof.

There are many familiar faces from other teams, a few ex Renault engineers, David Coulthard’s number one mechanic from Red Bull days, all experienced pros.

Wirth employs 120 people and the F1 programme is only part of what they do here, he has research and development contracts with Honda, Michelin, FIA and Porsche, who came to to them after being beaten by Wirth’s Honda car in ALMS. One of the recent programmes was to solve an aerodynamic problem for the IRL to prevent cars from getting airborne, which has now also been applied to sports cars.


Wirth’s pitch is that he has been focussing on the technology which makes a difference, particularly in the simulation world. He has two simulators here and I was allowed in to see the new one. It’s the first time I’ve seen a 3D F1 simulator up close and it looks a but like those ride simulators you find at the Science Museum or at shows – a pod on top of hydraulic rams, standing six feet off the ground. Both Timo Glock and Lucas di Grassi were there when I visited, correlating data from the recent Barcelona test and testing the Bahrain update kit.

The pod pitches and bucks as the car goes round the virtual Barcelona circuit. When the driver hits the brakes at the end of the main straight, the nose goes down probably a metre, it’s pretty violent. I noticed the rear end twitch in the high speed Turn 3. The virtual front wheels are visible on the screen, but there are no wishbones connecting them to the pod, which is the only thing that does not look 100% realistic – the rest is just spooky. Thanks to his work with Michelin, Wirth has devoted a lot of time to modelling tyre performance, which is the hardest thing to simulate.


I also tried on a virtual reality headset and standing in an office, was able to walk around the car and nose around the cockpit, as if I was standing next to it in the pit lane. It was uncanny. Even the wing mirrors worked!

Wirth’s plan for CFD-only design came from witnessing years of wastefulness in windtunnels, where £30,000 worth of 60% scale models are routinely built, tested and then thrown away every day. Many teams employ 140 people including model makers to do windtunnel research and Wirth decided that it could be dispensed with when he developed the 2008 Honda LMP2 car. The Eureka moment was when he realised that the CFD numbers were more accurate than the wind tunnel. Honda are convinced by it. He claims that the Virgin F1 car track data is closer in reality to the CFD numbers than any car he’s built before.

The Virgin car is around 4 seconds off the pace of the front running cars at this stage. In his view, the car lacks aerodynamic refinement compared to the Ferraris and McLarens because it is the first product from the design team, “We just lack experience compared to the fantastically clever people out there” – not because of the limitations of the CFD process. And just as the team at Force India has designed a much more aero efficient car with each passing year, so will Wirth’s designers. They have an aggressive development programme for this season so it will be interesting to see how far they are off the pace at the end of the season.

The design of the monocoque was frozen in June last year, probably three months earlier than the top teams who have greater resources and experience in manufacture. The team has a strict budget of €45 million all in and so far has hit all the deadlines it set itself. It will travel to Bahrain with two cars and a spare monocoque as well as five sets of spares for most parts. Wirth says that the troublesome differential, which has been causing the hydraulic leaks and destroyed their Barcelona test, has been fixed. There were quality control problems causing it to crack. But new spec ones are in short supply, so the drivers had better not crash into the barriers backwards before the race..

The front wing collapse was a “design error” by his drawing office team, for which he puts up his hands and accepts full blame.

“The drivers know that underneath them they have quite a good car,” he says. “Timo hopped out of the car and said ‘It’s doing what you said it would do.’ We have an exciting development programme, we should be able to bring a lot of performance to the car. We have a big update for Bahrain and more for Melbourne. There is a healthy development budget.

“I would like to show during the course of the year that we can close the gap on the weakest of the existing teams and show that this way of designing cars represents a way forward, ” he said.

Photos by Pip Calvert

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134 Comments
  1. Glen D says:

    Fantastic artical!

    I really do hope that Wirth can show as the season goes on that a team can make good progress without throwing vast sums of money at the car like McLaren and Ferrari.

    Will be an interesting one to watch!

  2. Andy C says:

    This is what F1 should be all about. Doing things differently, innovating and using new technology.

    I would like them to do well, mainly because I appreciate someone going against the grain, with a lot of conviction.

    Lotus and Virgin should be a real credit to F1 given the time to find their baselines and I think they deserve a great deal of credit for getting credible cars onto the grid. Its clear by the staffing of these teams that they should be serious race teams going forward.

    We’ll see how HRT is when they arrive in Race 1 and throughout the season.

    James,
    does anyone in the UK have an F1 simulator that they hire out? I’d love to have a go, whatever the cost!

  3. gaz909 says:

    I have to say – respect to Nick and the team. The mess that is USF1 has helped to really bring home exactly what the Virgin team has achieved.

    Without whinging, they have pit a car together, on time and within budget. They’ve tested, found errors and moved forward. They even have updates coming up for the first races!

    Good on ‘em. I wish them all the best. I really hope Nick’s CFD gamble pays off.

    Come on 2010 season! 1 week to go!!

  4. Fausta says:

    Good for him to keep with his CFD and attempt to take it the highest level. It will be interesting to see how far off the pace his car will be in the end. I have a feeling we may be pleasantly surprised!

  5. Henry says:

    “One of the recent programmes was to solve an aerodynamic problem for the IRL to prevent cars from getting airborne” Chuckle. I know its exactly what could happen but it made me laugh…do they not have engineers in america who can manage it!

    Lets hope the CFD approach demonstrates enough development over the year, it will be good to see one of the new teams on the grid making noticeable improvements.

    1. Henry says:

      Oh and that virtual reality headset sounds incredible, but I didn’t really see the purpose of it for the team? What does it enable them to do?

      1. Nadeem Zreikat says:

        Can we get one of those at least?

      2. Baktru says:

        To have a look at a car as if its next to you, without ever actually building a car? Or even a model?

  6. Matt Herbers says:

    For me, Virgin is the most exciting team on the grid. The team is a mold breaker. Smart people applying “outside the box” thinking along with Branson’s marketing prowess. We can’t expect any podiums, but all eyes should be on this car’s development in particular.
    If they can get inside the top ten on merit this season while maintaining their budget and lean team headcount, they may be creating “the blueprint” that other teams will need to follow.

  7. Alistair Blevins says:

    Very interesting article.

    I’d like to get my hands on one of those simulators, although not sure girlfriend would agree. She’d never see me again, except to put the occassional laurel wreath around my neck and hand me a big cheque and bottle of champagne.

    I think CFD and 3D digital rendering is the way forward in a cost constrained world (although I would imagine hardware, software and CFD-engineers are not cheap).

    It’s right for F1 too; being at the forefront of technology. Models and big fans seem a bit yesteryear.

    How quickly can the established teams scale up to this challenge – especially when so many have invested heavily in wind tunnels in recent years?

  8. Luke Dalton says:

    like the sunshades! quite a tall chap is wirth

  9. DanielC says:

    Makes USF1 seem like a serious bunch of amateurs.

  10. Pierre says:

    Great article James.
    I would have like to see pictures of these computers and simulator but imagine you were not allowed to take these!

    1. James Allen says:

      Afraid not. Another time.

  11. PAD says:

    Maybe USF1 could still be at the first race – if only by borrowing Wirth’s simulators and driving around virtually.

    Sounds like a fun day out!

  12. smellyden says:

    James,

    I take it with the RRA that testing in the wind tunnel will be limited. But does the CFD and virtual reality world Peter Wirth has developed suffer from the same restrictions? You said teams are more and more using computer simlations to test the car and develop thier drivers, would you feel the Virgin team are a ahead of other teams that you have seen?

    1. James Allen says:

      Yes it is limited.

      1. Nick Someone says:

        Interesting.

        How is it limited James?

        Processing power per season going to the simulation or something?

      2. gil dogon says:

        Do you care to elaborate on that James? In which way is CFD limited by the rules except for the obvious budget considerations (Doing CFD also costs money of course). Is there currently any limit on the computing horsepower teams can use?

      3. James Allen says:

        No it’s a resource thing, manpower, hours and so on, as far as I know

  13. Jon says:

    It’s an interesting concept, and if Virgin do end up being the best of the new comes over the year it would be classed a success. If that does become the case, do you see other teams taking this approach?

  14. JohnsonsEvilTwin says:

    Very interesting insight James. How long before all teams are CFD only? Surely just a matter of time.
    That virtual reality computer and those goggles remind me of “The Lawnmower Man”…The future is here………..

  15. Chris D says:

    A very interesting article. I’d appreciate more articles like this about F1.

  16. Kieran says:

    Being a Sheffield boy I’m terribly excited to see what Virgin Racing are going to achieve this year. Nothing like a bit of northern grit to get in the smooth mechanisms of Formula One, maybe surprise a few people.

    James,

    Bearing in mind the general Stimtech team disaster in the early nineties, what is the difference in Nick Wirth’s attitude now? Do you think he is still the enthusiastic mad scientist as he always appeared to be, or do you think the years away from F1 have changed his attitude a little? After all, apparently he was saying very similar things about CFD when he started Stimtech.

    Also, should I put my money where my mouth is and go and put a fiver on Virgin to score a constructors or a driver point this year – or is that a loyal step too far?

    1. Matthew says:

      I seem to remember that Simtek simply didn’t have enough cash to keep going. They had various sponsor problems, and their deal with MTV didn’t actually bring in any money, but let other partners advertise on the channel.

      Sounds familiar actually…

      1. Kieran says:

        Oh dear, that doesn’t bode well!

        I’m hoping the actual Virgin team have some proper sponsors money behind them, it looks like they do.

        I read somewhere that the Stimtech team actually had a really slow car as well, five seconds or more off the pace…..

        Oh double dear…. ;-)

  17. Kedar says:

    Hi James,
    May be this is a silly question, but if CFD only design is so good why arent the big teams doing so? I would atleast expect Renault who won the WC with Alonso spending the least amt of money to have already adapted this.

  18. Richard Hazenberg says:

    James,

    Hi. Firstly, I would just like to say I have really enjoyed your analysis of testing this year. My question is to do James, my question is to do with strategy this year. Will it be possible for a team to run their first stint on one tyre compound and then pit on the last lap to put the other compound on; before crossing the finish line in the pits? If so this would negate some of the time lost in a pitstop and could be a viable strategy for a car that is easy on it’s tyres.
    Best wishes,
    Richard.

    Richard

    1. hibikir says:

      It’s not really a viable strategy, because even after only half a GP, a tire switch, even to the tire that isn’t really the best for the circuit, the car with the newer tires is 4 seconds faster than one that hasn’t pitted.

      For a team to have tire management so good as to make a last lap change optimal, they’d have to manage so little tire wear as to break the laws of physics.

  19. TM says:

    I guess I can understand the, almost fear, people have of vastly reducing budgets – that suddenly F1 will be diluted and turn into a lesser formula. But this story is an example of how exciting it can be, and that it can promote real innovation.

    If a budget cap (low enough) could be put in place it would surely enable the rules to be opened up vastly and teams would really be able to innovate rather than spending millions on refining silly tiny little endplates and such. It would show who is cleverest and lead to exciting developments and variation between cars.

    As Martin P has perfectly put before, a team spending £400m beating a team spending £40m doesn’t show any sort of superiority.

    Go Virgin!!

  20. daniel says:

    I think that anyone has to wish this team good luck, and i certainly do. I think that Simtek had potential, but they had sponsorship issues and couldn’t continue, I hope that Nicks second attempt is more successful.

  21. Pierre says:

    Something off this topic, maybe it’s already been discussed, don’t know.
    There is no refueling this year, teams will try to have the lowest car at every moment of the race so it will be a disadvantage to carry extra unnecessary kilos.
    I’m so wondering what will the drivers do with fuel when they are behing the safety car when speed is limited so the fuel consumption is lower. Will they try to burn these extra unused kilos when behind the SC and so run high rpm engine? Is there an engine programm setting that will do it automatically? If it happens before the pitstop, one could imagine they could preserve this fuel to delay it, but I do not think it will happened. But if there’s a SC after the pitstop drivers will need to burn these extra kilos.
    Same if it’s suddenly raining during the race?

    1. James Allen says:

      I’ve done a bit on this already. Yes they will burn fuel behind safety car using ultra rich setting. Watch out for flames from the exhausts!

      1. James Alias says:

        why couldn’t they save the safety car fuel and then burn extra with ultra rich settings once the race is back on? richer fuels means more power output ain’t it?

      2. Martin says:

        It might be that the fuel weight is a greater penalty over the laps it takes to burn off than the power gain over those same laps. I don’t know what mixture ratios F1 cars run. Cars running rich with black smoke and flames on overrun, e.g. modified Skylines and WRXs and the V8 supercars in Australia tend to run about 10:1 or 11:1 air to fuel ratio. I think the F1 cars are probably closer to the stoichiometric value of 14.3:1, but that is based on TV observation.

      3. Matt says:

        They could, but it makes sense to do it while you’re at a restricted speed.

        If one driver burns off 10 kilos under safety car, and so restarts 10 kilos lighter he’s going to have an advantage for several laps over the guy whos running rich.

        Oh it’s going to be a real treat for the greens to watch fuel virtually flowing out the back of the car under safety cars. HAHA

      4. Stephen Kellett says:

        Not neccessarily. Too rich and some of the fuel doesn’t get burnt and then becomes a burden, preventing efficient ignition.

        If you’ve ever experienced “flooding” your car when trying to start it then thats and extreme example of this.

      5. Spenny says:

        It’s a weight thing. Once they have enough fuel to get to the end, all the extra is baggage slowing the car down.

        If a car was marginal, yes, they would use fuel saving to give them the benefit; otherwise, it is about getting rid of the weight that the fuel represents – they use massively less fuel on safety car laps than racing.

        Bear in mind that they will have fuelled for an optimal race, so any extra fuel most likely represents a sub-optimal strategy. At the back of the field, there may be drivers who have gone on a low fuel strategy expecting a safety car (Renault perhaps!! :) )

      6. Ahlapski says:

        Richer mixture does not necessarily means more power. When you are running lean … yes.

        But when you are running at optimum which I presume they are, richer mixture could leads to a drop in power. Is that right, James??

      7. James Allen says:

        Don’t know, but it would certainly lead to ‘dumping’ fuel weight

      8. PAD says:

        That’s not going to look very environmentally friendly.

        Perhaps they could have said that the weight of any fuel at the end of the race -ie saved – would be taken off the car’s weight at the next race. That way it would be an incentive to use less fuel. It might have the consequence of someone driving extra efficiently in one race to ensure that at the next they are notably lighter

      9. Kedar says:

        But isnt this again like the good old Qualy with “Fuel Burning” period?
        with Oil touching 78$ a barell I am sure this is not the last we have heard about this issue

  22. Bec says:

    CFD is the future of F1 design, OK it’s not there yet but it’s inevitable. Computer power and technology is progressing at an exponential rate, so it’s a matter of when not if CFD over takes the traditional wind tunnel.

    And remember even wind tunnel designed cars have been monumental failures in the past, and not too recent past at that, how many times have we heard, “the figures we got in the wind tunnel don’t seem to match the real world”.

  23. Stephen Kellett says:

    “Timo hopped out of the car and said ‘It’s doing what you said it would do.’

    Thats an endorsement if there ever was one.
    You predict what it will do, put the spec in the simulator and test it, then do it for real and its the same. In a few years, this will be the team to beat (unless the others get similar tech).

    Likewise, having beaten a competitor and for that competitor to then come and hire your consulting service. That is a very strong endorsement.

    Should be a very interesting team.

  24. Stu says:

    No one is expecting the new teams to be on the pace of the current teams. You only have to look at Spa 09 and Monza 08 to see that there aren’t any mugs left in F1.

    The real thing to watch will be how the car is updated throughout the season. If CFD is as good or even better than using a wind tunnel then it should mean they can design and test new parts continuously. And manufacture the ones that work. Compare that to BMW who just looked like they chucking any old thing on and hoping it would work.

    If they can end the season as being the best of the new teams that will be a fair achievement. But if they can do that whilst being able to run some of the older teams close then that’ll be a massive achievement.

  25. Dave P says:

    Very interesting. F1 definitely needs Nick and his ideas… maybe in the long term he may be proved wrong and cannot get the last 1% performance that a wind tunnel gives… but to learn so much along the way as they will fantastic!

    Interesting in that I would separate the 3D aspects from the CFD.

    I work on MRI scanners where they have had 3D modeling for many years, there you can bend down and put your head inside someones brain looking out from the inside… amazing.

    I love these detailed articles James, it must have been a fascinating day…

  26. S.J.M says:

    Interesting read, It would be nice to see their car(s) having a problem free time in Barhain to see just how quick they are compared to the limited testing runs they managed before the inevitable happened. Im liking Lotus & Virgins approach to the season and whilst they had had teething issues, it was to be expected of any new team and I hope they both do well. And its nice to see an insight into the works of a smaller team and not the hightech & expensive bases of the top teams.

    I think it is fair to say that the paddock will be keeping a close eye on Virgin’s progess (certainly compared to Lotus/Hispania), if only to see if an all CFD approach is a viable option in designing their cars for future seasons and to cut out windtunnels / save on costs?

  27. Gary says:

    An interesting piece James, especially the 3D driving simulator. I hope they have some slimline 3D goggles to wear with a helmet!

    The big F1 teams devote at least as much, and probably more resource to CFD using similar tools and similarly bright engineers, and they have the opportunity to validate their models against wind tunnel data. There is no way Virgin (Wirth Research) can have a competitive advantage in using CFD only. Wind tunnels actively help the refinement of the CFD models so however accurate he thinks his CFD data is, my betting is on the big F1 teams have yet more accurate CFD. If they can ever get agreement on applying budget caps fairly and transparently and if the budget cap is set low enough, then I can see Wirth Research’s approach as potentially having a competitive advantage, but that isn’t the situation today.

    But I wish them well, they’re clearly well organised and have a programme that they’re executing against.

  28. Virgin and Nick Wirth certainly sound like they have everything under control, with some good planning and organisation happening. Maybe USF1 if they are granted an entry for 2011 could learn a thing or two, like locking in the monocoque design, nice and early.

    I like the CFD approach, certainly seems to be a lot more economical than wind tunnels. I wonder though if the other teams will complain, given there is restrictions on the amount of wind tunnel testing they can do, but no limit on CFD modelling, or whether they’ll also start to use CFD more?

    Also how cool is that virtual reality setup!

  29. Martin Collyer says:

    I’m pleased to hear that he is a fan of The Who, perhaps Gordon Murray can be tempted to work there.

  30. Chaitanya says:

    Great article. I really think these guys could surprise some.

  31. Chris C. says:

    Good luck to them, most probably they will be just the early adopters of what will be standard practice in the future.

    James, you are quite experienced. Do you share the claims by Wirth that their current problems have nothing to do with their aerodynamic modelling but rather with the aerodynamic input by the design team?

    1. James Allen says:

      I’m waiting to see for myself when the racing starts and we see the cars developing

      1. Scott says:

        The thing with computers is that if you put bad data in you get bad data out.
        Good luck to them, I hope they can get a solid season behind them and have a good base to go forward. At least they seem to have a rational plan and a firm direction.

        James do you have any idea how their simulator compares to other teams? You mentioned they are able to do accurate tyre modelling which I think the McLaren is also able to do (and possibly others) yes?

      2. James Allen says:

        I think the tyre modelling is the key thing and the area about which the least is known. Wirth feel that they have made some big strides in this field.

  32. FaithHealer1 says:

    Well this is a team I’m definitely supporting this year. Any team that uses photos of The Who in their research centre is a team I want to do well!

  33. Howard Hughes says:

    Wow.

    What an excellent article. I’d barely heard anything about this team so far, apart from a few desultory headlines, but suddenly after reading this I feel like really rooting for them! Your initial statement is a really bold one though – do you genuinely think that Virgin will be the fastest team in the whole of F1 once they hit their stride? If so that’ll be a remarkable achievement.

    Either way, this is a great insight into Wirth and how the team are going about things – I can understand much better now how Beardy Branson feels like they’re worth backing…

    1. henri says:

      Best of the NEW Teams!

  34. Nathan = says:

    Great read! Very insightful.

    I think CFD has so much more potential too.

    I’m surprised more teams don’t do more extensive development with CFD. I know Adrian Newy has a lot of faith in the technology, more so then almost anyone and uses it more then the rest of the top teams. It seems to be working for RedBull..or is that just Adrians genius at work?

    I can’t wait to see the Virgins out on track in race conditions, theres quiet a few very varying designs this year.

    Thanks for the insight into Wirth Research!

  35. Rick J says:

    I really wish this team every success. It seems to me they are using their resources with great intelligence and efficiency. Too bad F1 isn’t about competing to get to the moon for an inaugural lunar GP. You have to think these guys would be right in there.

    1. Laurence H says:

      I believe Bernie is in discussions with the Moon to try and get them on the calendar for 2011. Hopefully a night race…

  36. CHIUNDA says:

    Let us see if he can achieve what he says he can because that would give the budget-cut movement alot of credibility

  37. Chris C says:

    Fantasitc!!!!
    I didn’t know the Pet Shop Boys where still going!!! (pic #2)
    Always new you where multi-talented.

    Cheers James.

  38. Adam Taylor says:

    A very interesting insight into the Wirth Development company. I am interested to know how much more cost effective it is for them to use the CFD method than the wind tunnel and also whether, given the cost restraints, he has any plans for any major upgrades given the information gathered from the Barcelona test?

  39. Craig March says:

    Knowing nothing about the process in developing an F1 car I still think you have to admire the guts and ingenuity in Virgin’s development process. Fair play to them. One day all the teams could be copying this process.

  40. Mani says:

    That was fascinating, thanks James.

    It’s fantastic to see a new team doing something innovative and the people doing it like Nick Wirth have a track record of success with it. Do you think the likes of Mclaren/Red Bull/Mercedes will have a CFD giant cumputer system already or will they now rush out and get one built? I think Ferrari recently opened such a system didn’t they?

  41. rpaco says:

    Excellent! V interesting that the real figures matched the CFD better than wind tunnel models. Buy only when they have the updates on the car and it matches the front runners for pace, will people believe that wind tunnels are unnecessary.

  42. GP says:

    Great post, James!

    It will be interesting to see how the car evolves over the course of the season. Both Adrian Newey and Ross Brawn have said in recent interviews that they can’t see designing an F1 car with CFD only.

    What intrigues me though is “When the driver hits the brakes at the end of the main straight, the nose goes down probably a metre,” why would it move so much when the real car hardly dives under braking?

    1. Just a bloke says:

      The movements of the simulator help to give the occupant a more realistic feeling. When combined with the visuals inside the simulator the occupant gets a much higher fidelity overall effect.

    2. Martin says:

      The dive is to allow gravity to provide an analogous sensation to the braking force in an attempt to give the driver some feel.

    3. def says:

      I would imagine that this to use gravity to simulate the g-force experienced under braking.

    4. I would imagine it’s to try and give the sensation of braking. As the simulator’s stationary, leaning it forwards will give the occupant a slight increase in “forward” G.

      1. GP says:

        But 1 meter?? I don’t get it.

        An F1 car hardly dives under braking. It is actually very important for the best possible aerodynamic efficiency.

        Now, if a team is testing different setup configurations how can the driver feel the difference when the reaction of the simulator is so much different than the car’s? In other words, say a team is testing softer front springs, this will cause the front end to dive more under braking. If the extra dive is a few millimeters, it obviously makes a much greater relative difference on the car – which hardly dives under breaking to begin with – and the simulator – which, evidently, moves down 1 meter. How can the driver feel the effects of a slight difference when the simulator violently drops 1 meter in a fraction of a second?

        If Adrian (Newey) or Ross (Brawn) is reading this, please share your wisdom…;-)

      2. Let me explain. As Adrian and Ross may be a little busy this week.

        In an F1 car, under breaking, there is no noticable dive. However, the driver’s body is inclined to keep going forwards, restrained only by the safety harness.

        In a simulator, there is normally no such force acting on the driver’s body because it is stationary – i.e. not moving forwards. Therefore, to SIMULATE that force, the simulator unit tips forwards, meaning the driver’s body is inclined to move towards the front of the simulator, similar to what it does under breaking in a car.

        This tipping, along with what the driver sees and hears and feels in the simulator, fools his brain into thinking he is breaking.

        Simples.

      3. Baktru says:

        How much the car moves and how much the simulator moves have NOTHING to do with each other.

        When you brake hard in a car, it feels like your body wants to continue going forward, conservation of momentum and all.

        The dip of the nose of the simulator, makes you feel the same, as if you are ‘falling’ forward in the car. In this case it’s gravity rather than momentum, but the feel should be somewhat similar.

      4. GP says:

        Topless Porridge and Baktru, I appreciate your replies but your are missing the point of my question.

        I know what the simulator has to do to provide some feedback to the driver. However, a simulator is not primarily used for the development of the driver it is for the development of the CAR.

        If you go back to my last post, my question remains unanswered i.e. how can such large movements of the simulator provide accurate feedback for changes that are always small increments or improvements of an existing part. I assume that the engineers can measure the comparative differences between parts but I was looking for a more precise explanation.

      5. Nathan says:

        Yes,

        Much like these units (boy, i’d love to have one of these at home!)

        http://www.force-dynamics.com/
        http://www.youtube.com/watch?v=MNhfulLJPcY
        etc

    5. Marcus Redivo says:

      To be clear, there are no car parts attached to the tub; no wishbones, no steering linkage, no springs, no dampers, no wheels, no brakes.

      Instead, there are a series of hydraulic rams attached. These rams can position the tub in any attitude necessary to simulate G forces on the driver, for example, on it’s side to simulate cornering, and nose down to simulate braking.

      The engineering involved is, to calculate from the driver’s inputs the attitude changes to induce. Full hard on the brake pedal while simulating my Smart car would be, say a 15-degree nose-down attitude; stepping out of the simulator and repeating the action in my Smart should feel the same. For a Formula 1 car, the nose-down would be more pronounced, because there are higher G-forces to be simulated.

      If the simulator is accurate, the driver’s inputs (all logged, I presume) are representative of the data that would be collected by driving the actual car around a track. To the degree that this is the case, the engineers have correctly understood and solved the problems they were working on.

      Accurate simulation is critical to getting accurate inputs from the driver. Accurate inputs from the driver are critical to making correct design choices.

      All that said, the only simulator I have had the pleasure to experience was at Disneyland. I must say, even the potholes seemed very real. The technology is amazing.

  43. James D says:

    James,

    After seeing the factory and meeting the guy you are obviously impressed. What’s your gut feeling about his design philosophy? Do you think it will catch on? Do you agree with him when he says he’ll catch the weakest of the existing teams before the end of the year?

  44. Guy says:

    James

    Thanks for the insight into a new venture which may change the way we know F1.

    Please keep educating us on CFD. Just really slowly

  45. Russell says:

    Looks liek a good idea, sounds like a good idea but lets wait and see!

  46. Peter Brito says:

    Fantastic article James!

    Had no idea that Wirth was that experienced. I must say that I’m impressed that Branson had the courage to step away completely from the Brawn Team and focus on this impressive grass roots and innovative approach with Wirth.
    I really hope they do succeed with achieving their objectives for this year; as I really think there is a lot of money burnt through inefficient development methods. F1 shouldn’t be about the team with the biggest budget winning championships (e.g. Ferrari with Schumacher) but serve as a platform to encourage more innovation.

  47. Brace says:

    Thanks, James. I really enjoyed this text.

  48. Zami from Melbourne, Australia says:

    Time will tell. Best of luck by all means. Sounds like a good cause. Hopefully he’ll stick around long enough to prove with some examples. Jenson Button won his 1st Grand Prix in a chaotic race as well. That was more of an accident than a result to me. So, I really hope what Wirth said aren’t just a big hope only. I’ll wait for the examples.

    By the way James, what car(s) do you drive everyday?

    1. James Allen says:

      Land Rover Discovery 3 TDV6

      1. Zami from Melbourne, Australia says:

        Would love to have a street race against your rover with my Holden Cruze CDX. It’s 2.0 ltr, 4-cylinder SOHC turbo. Maybe I’ll get to see you when you are in Albert Park, it’s just 15 minutes from my house

  49. Rons best mate! says:

    Part of me thinks that this will be a waste of time, as the big teams would do it this way if it worked, BUT if VR can prove it works well “enough” then it should allow other teams to go the same way and may end up reducing th cost of F1 entry each year – which can only be a good thing!

  50. monktonnik says:

    I think that Wirth and Virgin can be rightly proud of their achievement.

    If they can produce a car that is close to the ultimate pace of the front runners using CFD only, then you could argue that as part of the resource restriction agreement the use of wind tunnels should be banned.

    I know that there are lots of arguments for keeping them open, but my question to anyone who contests this is this; how can you justify an expense of £30,000/day when there is a comparable technology that has been proved to do the same job for much less money?

    Would the spectacle of F1 be damamged if the cars were 2-4 secs a lap slower because of less refined aero?

    1. Zobra Wambleska says:

      Probably not, but no one is going to leave that much time on the table if they know how to pick it up.

  51. Anders says:

    Great Story Mr.Allen! It is going to be refreshing to follow Wirth and the Virginracing team throughout the season and their ideas and development of their car.
    I think this is the future route to take

  52. Jeff says:

    Great to hear. Would be great for F1 if all teams were capable of getting on the podium or winning.

  53. Bert Knops says:

    Quite interesting. This was the first time I read that CFD-numbers are closer to windtunnel-numbers nowadays. However, I do have my doubts when Wirth says his car is basically aerdynamically unrefined in comparison to the cars of the established teams.

    I think CFD is definitely good enough to build a good racing car, but F1 cars are a whole lot more complicated than sports cars, both internally and externally. I wonder if his current designing software is up to the task, when Branson wants Virgin to really start performing. Any thoughts on this, James?

  54. George says:

    Sweet shades James!

    I’m growing steadily more fond of Virgin, it seems like a very professionally run team and the quotes in your piece are refreshingly honest, and make sense.

    I’m also quite proud that it’s a British team bringing this new system to F1, the big teams seem to be stuck in a rut with regards to wind tunnels. Their view seems to be ‘if it doesn’t work, buy another one’

  55. Richard Mee says:

    Yeah… sounds flash, but does it beat Forza 3 on the ’360?
    ; )

    1. Baktru says:

      Nothing beats Forza 3 on the 360 :)

  56. Ahlapski says:

    “Of the new teams in Formula 1 it looks as though the radical Virgin Racing car is probably going to be the fastest” … James, I didn’t think you’ll say that. Because they weren’t looking too good in the tests are they?? But having read what you wrote, you could be right.

    I still think they would be neck and neck with Lotus though.

    I think, as I said a couple months ago, that this would be this is the future for F1 and I still think so…

    What are your thoughts, James.

  57. Eric Weinraub says:

    I am expecting this approach to pay off.

  58. Mr Spindles says:

    So regarding the “eureka” momement…did any spill the beans on how much closer to reality CFD is than wind tunnel testing??

  59. Dave+Kim says:

    Thanks James for such a fascinating insight! Your great reports help satisfy our F1 appetites. I wonder if they’ll get a video-games version out for Christmas?! ;-)

  60. Peter Jones says:

    Excellent write up.
    I think it’s amazing that anyone can build a respectable F1 car in such a short amount of time. The fact that Virgin have managed it without relying on any of the old techniques makes it even more impressive. I hope it’s not going to take too long before they can iron out the problems and be in a position to score some decent points.

    P.S. What was your lap time in the simulator?

  61. gil dogon says:

    Well, I am software/computer developer with some strong background in math and physics and always had a dream of working for an F1 team. Maybe if I was 20 years younger and living in England I would try to get a job at Virgin! Anyway I do believe that CFD is the way forward in F1, and is probably much more cost effective once you get it right. I hope indeed Virgin can prove this at least by winning the bet against Lotus. This will be another interesting back story to a season already full to the brim with other ones.

  62. Fazz says:

    Fascinating stuff!
    That’s why Branson jumped aboard no doubt..

    Will be very interesting to monitor progress.

    Thanks for the insight.

    1. Neil says:

      Branson is in business. He jumped aboard becasue it was the best promotional return for his money.

      I’m not being cynical. It’s just that you don’t make millions by following your heart!

      Neil.

  63. Patrickl says:

    Really nice view into how this CFD design idea is coming about.

    Thanks!

    It’s odd how Adrian Newey says that windtunnels are cheaper though. Or rather that you can go through more design parameters in a shorter time with them. So you’d need less time to do the same thing with a windtunnel.

    Didn’t they say anything about that?

    1. Tim says:

      I think Newey’s point was that you can get much more data from a single run in the windtunnel than from a single run using CFD – which needs about 20 runs to produce the same amount of data. Whether a single run of CFD is less than a twentieth of the cost of a single windtunnel run I don’t know – it probably varies from team to team, depending on the different equipment.

      But this is covered in the article – with a windtunnel, teams need to construct accurate 60% models to put in the tunnel which can cost tens of thousands of pounds. If they don’t show an improvement then they’re useless and have to be thrown away. But with CFD the designer can create a new part or concept on screen, map it over to the CFD and run it there and then. No time and money wasted building a model.

  64. Mike from Medellin, Colombia says:

    James, who takes the photos? Did you work with Darren Heath on this?

    1. James Allen says:

      Pip Calvert did these

  65. Nathan Smith says:

    I think this year could be a struggle for virgin but if Richard Brandon sticks with it they are well set for the future.

    Any chance of an article on McLarens rear wing James?

  66. Nathan says:

    Thanks for the insight James.

    I think their process is fascinating (coming from the IT world myself, and also being a car nut), and the comparison of their performance improvement vs the traditional wind tunnel biased teams will be on of the more interesting aspects of the current season to watch.

    As someone who has also followed Richard Branson in the business world, and knowing his style (doing things a little differently) I could well imagine his enthusiasm when talking to Nick about a totally CFD designed car with the Virgin name on it.

    Good luck to them I say. Bring on Bahrain.

  67. Dermot Keelan says:

    Best of luck to Wirth and the Virgin F1 operation. They are doing their business in an efficient and sustainable manner and it looks like the CFD-only model is a feasible alternative to wind tunnel and CFD testing. If CFD produces more accurate results then why waste time with wind tunnels. I’m firmly routing for them this year and I’m sure they’ll creep closer and closer to the likes of Toro Rosso and Renault as the year progresses.

    1. Gilbert says:

      If others teams use CDF and wind tunnel, it’s not for fun.

      1. Rich C says:

        No, but it falls into the “we’ve always done it this way” category, possibly revealing a stick-in-the-mud attitude.

  68. Maxime Labelle says:

    That’s because in order to simulate the violence of real breaking, it is necessary for the simulator to “dive” deeply forward.

    With his eyes locked on the screen, the driver is “fooled” By having physical sensations that somewhat match what is happening on the screen.

  69. Mike says:

    Great article James and very interesting.

    In my experience have found that CFD is limited by the quality of data input and the analysis and interpretation of the output data.

    Correlation with actual physical testing, which is what the more established F1 teams will be doing with their windtunnels, flowvis and other devices used during pre-season testing, is what is needed to validate the CFD results, which in turn leads to a greater understanding of the components aerodynamic properties. Without validation it could lead to taking a wrong design direction and ending up with a poor car.

    Although saying that Nick Wirth is an extremely talented Engineer and good luck to him and his team, it’ll certainly be interesting to see how the team develop their cars through the year.

  70. JonW says:

    So, if I understand the Wirth phylosophy – by dispensing with the wind tunnel, not only can a great deal of money be saved, but they should be able to develop more quickly than a team that is spending time on building models and putting them in the tunnel.

    If that is true, they should gradually migrate up the grid as the season progresses, it’ll be intersting to see how they get on.

    It must be greener too. All those models that aren’t being built and all that power that wind tunnels consume not being used.

  71. alex m says:

    A great piece, as ever James, quality information and insight that is sadly lacking everywhere else.

    I cannot help thinking most posters are somewhat missing the point. Virgin are not really trailblazers, CFD is not new. They are skinflints trying to save a lot of money by relying solely on CFD. This is a great risk and is arguably somewhat arrogant. Some of the worlds greatest minds are currently working in F1, engineers and programmers, they have unlimited budgets and are free to try anything they fancy. The universal feeling of these people about CFD is that it is a great tool to help, alongside others, but, specifically, that while the emerging technology is great, the application to designing something as complex as the whole car is far too much for this emerging technology right now.

    If you have an interest in promoting this as the way forward, you will paint it in a certain way. Branson’s Virgin brand has a PR image that just suits this, he can paint himself as the plucky underdog trying new technologies on a small budget, but in the views of most F1 engineers, Virgin/Wirth are taking a massive risk.

    The fact that the car seems fast is very interesting, but if it falls away or does not perform, will they just use it as an excuse for whining about budgets and try to force F1 to cap spending, ultimately all part of Max Moseley’s attempts to attack his enemies in the big teams. Remember the murky “help” Alan Donnelley gave them getting on the grid, ahead of far better qualified teams, whilst simultaneously working for the FIA….

  72. Dave P says:

    James – with teams reportedly 4 seconds off the pace, is there a potential for teams to miss the qualifying cut level of performance? and if so, would you expect the FIA to find a way to allow them to race regardless early in the season?

    1. James Allen says:

      There is no cut off

  73. Frankie Allen says:

    Everything I have seen so far from Virgin is more Mickey Mouse than Avatar. The problems they have so far, in no way resemble professional. Many teams have CFD and I really doubt Virgins is the best. Without experimental results to back up / fine tune the CFD model you can be just guessing on very major issues. I am really struggling to describe the level of naivety I believe Virgin have brought with their overall approach, highlighted by the practical issues they have experienced so far. I appreciate this is not necessarily the views of the author, but of Virgin.

  74. catalina ;) says:

    so Nick is mad fer it? :D
    I’m his fan now xD

  75. Nick172 says:

    Hey James,

    That F1 Simulator at Virgin HQ is great isn’t it? There’s a good video of it being tested here:

    http://www.youtube.com/watch?v=ZF_dnGVbXkM

    1. James Allen says:

      Cool video but it’s nothing like that, I can assure you!

  76. murray says:

    It’s always seemed to me that conventional wind tunnel tuning is all about where you locate the pressure sensors, as more and more sensors and readings become available for simultaneous interpretation, we’ve seen more and more barge boards, “mirror mounts”, and addons. Perhaps Wirth’s faith in CFD is better placed because of the current restrictions on appendages, allowing the computers to approach a more complete holistic aero picture of the car than would be possible with addon tuning. It still demonstrates the disproportionate amount that aerodynamics contributes to the cars, though. If Virgin do improve dramatically during the year, it’ll probably be because they’re better placed to understand results of “virtual testing” than other teams. It will be cheaper than running cars in testing, but it’s as ludicrously arcane as ever. Horsepower is limited through engine development controls, limiting downforce to x amount in x tunnel or x program makes even more sense. It would make F1 more sensible as a development environment to tyre manufacturers, rather than an insular PR environment for a single spec maker. Imagine cars coming into corners having to consider braking, corner speed, exit line acceleration if they’ve all got comparable aero grip. Put the emphasis back on mechanicals!
    Sorry, Nick, I admire your ability, but F1 is paddling further and further up an irrelevant backwater. Can’t help but wonder how a Paul McReady design would go, if he was interested in F1.

  77. Andy, I would love to have a go too. I was actually going to ask here if anyone knew how the average person would fair if put in one. I would take it really seriously if I had the chance. Wonder if there is one you can hire would love to try.

    Chris.

  78. Tom says:

    An excellent, insightful article.

    Just one point – Manor’s HQ is in Rotherham.

    It’s not as hard to believe as you might think that a F1 race team and cars will be equipped, based and resourced in the former pit village of Dinnington, Rotherham.

    Coincidently, Rotherham is also home to F1 Show Cars – the proud owner of the only 3-seater F1 Simulator to date. Available to hire with virtual reality goggles included – http://www.f1showcars.co.uk/

    1. adam says:

      previously owned by the arrows f1 team to add!

  79. Interesting “The Eureka moment was when he realised that the CFD numbers were more accurate than the wind tunnel.” Exactly how can anyone make that claim. A wind tunnel is used to verify the CFD result and show how far it is in error, not the other way around.
    Seriously this has to be a misprint.

    The more you know about CFD the more you understand its limitations, the less you know the more you imagine it can do.

    1. James Allen says:

      Thanks for that. Please tell us more..

      1. Sure James no worries.

        In order to compare one thing to another you need a frame of reference. In classical science and engineering, empirical formulas are used to make estimates that are correlated to experimental data. This works great for calculations such as the strength of a straight beam and the mass of an object, but for fluid flow problems there are no empirical methods for computing the exact flow over an arbitrary complex shaped body let alone the flow over a F1 car. Hence the only way to determine the definitive flow as well as the lift and drag values on a car is with a calibrated wind tunnel. That is the frame of reference. You then compare the measured results to your CFD simulation and determine the error of the simulation not the other way round. These are basic fundamental principles of experimentation and simulation.

        When talking about the accuracy of a CFD simulation you need to consider the accuracy of the turbulence model used in the simulation. The reason being is the lift and drag values on the car are highly sensitive to turbulent flow separation in the boundary layer.
        There are several ways to model this turbulence in CFD, ranging from the most accurate DNS (Direct numerical simulation) and LES (Large Eddy Simulation) to the least accurate approximation method, RANS (Reynolds-averaged Navier–Stokes). F1 teams all use the RANS turbulence model.

        The reason you ask? Well it’s all to do with the mesh, the mathematical base model where the Navier Stokes equations are solved.
        The teams use either a tetrahedral mesh or a trimmed polyhedral mesh, which are generated by an automatic meshing program that requires a relatively low level skill to operate. The biggest problem is you can only run a RANS turbulence model on these tetrahedral meshes. They also require enormous computing resources and worst still produce fictitious results that can be completely misleading. Hence the reasons why F1 teams still keep and use their wind tunnels. They know from experience that a CFD model will generate fake vortices’ and completely miss other crucial ones.

        The only way to produce a CFD result with any level of respectability and degree of accuracy is to use a high quality all Hexahedral mesh running a transient LES turbulence simulation. The next obvious question is why don’t the teams use this method? Yes indeed that is a very good high tech question.

      2. James Allen says:

        Thanks for the insight

  80. Craig D says:

    It seems other recent posts have already covered some of the points I was going to write (with Peter Murdoch being very informative), but yes, it appears a fair few posters have got themselves confused over Virgin’s all-CFD (computational fluid dynamics) designed car, thinking it to be a massive innovation and cutting-edge thinking.

    Firstly, all the teams use CFD as well as wind tunnel testing. Indeed, no doubt the likes of McLaren and Ferrari, etc, will likely (I suspect) be using CFD more extensively than Virgin, such is their resources. So it’s not as if Virgin is being radical in the sense that they’re using some super advanced technology and methodologies. In truth, it’s quite the opposite and they’re being less sophisticated (but are saving time and costs) by not using a wind tunnel/CFD combination.

    I feel that some people are thinking of comparing wind tunnel testing to CFD as akin to VHS to DVD or something – i.e. that wind tunnels are a ‘manual labour’, dinosaur way of doing things that the ‘old’ teams are stuck in their ways with, and CFD – being all digital and whizzy computers – is by definition more accurate and better quality. This is the wrong way to look at it. CFD is not analogous to someone who has a calculator (the CFD engineer) being able to do calculations many times quicker than another chap stuck trying to work with an abacus (the wind tunnel tester). Heh, how many more analogies can I conjure up – I’ll stop there!

    Peter Murdoch has already well surmised the deeper technicalities of CFD, but in essence CFD is a way of mathematically modelling an aspect of the physical world (in this case fluid flow: air, water, whatever), and then using numerical simulations to understand and predict the behaviour of the fluid in various situations (such as the flow around the endplates of a front wing), and to calculate properties such as drag, (negative) lift force, vorticity, temperature, etc.

    However, whenever you mathematically model something you inherently have to make simplifying assumptions of the real world to arrive at a suitable model amenable for analysis; it would be impossibly complicated otherwise. So already you are approximating the real life phenomenon and so already you’re not going to be accurate as if you can see the real thing (such as the flow shapes in a wind tunnel – as long as it’s calibrated and you’re measuring instruments are suitably accurate).

    Now, modelling fluid flow is extremely complicated. Except in trivially simple situations, there are no exact solutions to the equations that govern the motion and properties (pressure, etc) of any fluid flow (these are called the Navier-Stokes equations and are basically just a sophisticated advancement of Newton’s laws of motion, i.e. Force = Mass x Acceleration, adapted for fluid flow). And by exact solution I mean it’s not a case where you can plug data into an equation, turn the handle and out pops your answer (unlike, say for an equation to model the growth of your savings account based on the interest rate, where you stick in your bank balance, turn the handle of the equation governing how interest is applied, and bingo, out pops your lovely savings for the month/year)!

    With CFD, to obtain solutions you have to approximate (discretise) the equations and solve them numerically on a computer. The key word here is ‘approximate’. In approximating something you’re by definition introducing an error into your answer (e.g. down-force figures), and in F1, errors can mean tenths of a second (or seconds if you’re the new teams – ah that’s unfair)! To obtain more accurate answers requires more computing power since you need to use a finer mesh (i.e. use more data points on the F1 car/component model) and a more complex model to simulate turbulence (cf. Peter Murdoch’s post above), and thus solve more equations.

    Now due to the complexity of the equations and geometry of an F1 car, it is currently impossible to use CFD to exactly model every aspect of the car. That is why wind tunnels are still worthwhile. Of course they need to be correctly calibrated, since like with CFD it’s a case of, put garbage in, get garbage out. Perhaps that’s what Wirth means in his “The Eureka moment was when he realised that the CFD numbers were more accurate than the wind tunnel” quote. But as mentioned by others, you need (properly calibrated) wind tunnel data to validate the CFD so that you know your virtual model is behaving true to life.

    Finally, here’s a summary of some of the advantages and disadvantages of CFD to wind tunnel testing, so that others hopefully can appreciate the worth of each and why it’s better to have a blend of the two.

    Advantages of CFD compared to wind tunnels:
    - Can analyse whole domains and measure many parameters (velocity/pressure, etc) simultaneously. Wind tunnels use sensors to measure a single point on the car (just like the sensors hanging off the McLarens in testing). Hence a whole wind tunnel run could be useful for just a handful pieces of data. Also, you have to ensure that these physical sensors in the wind tunnel don’t adversely disturb the flow you’re measuring too, since they won’t be there on track! By definition CFD calculates solutions across the whole domain investigated.
    - Cheaper overall since quicker turnover times than having to design, build (and bin!) models. Also parts on the car can be much more easily remodelled on the computer so you can test designs tweaks quicker.
    - Better visualisation of results. Computers can produce a wealth of informative graphs/flow patterns etc, and you can focus on design details of particular interest. Wind tunnel photos/videos don’t necessarily provide the same level of detail.

    Disadvantages of CFD compared to wind tunnels:
    - Results can be erroneous. It is well known that in some circumstances CFD results do not coincide well with reality. This is notably the case for complex turbulent flow (which is pretty prevalent in F1 eh)! Example problems include: overproduction of turbulent energy in wakes and incorrect generation of vortices/ vortex shedding. Thus due to the difficulties of modelling and unpredictive nature of turbulence, a CFD model could predict that the vortices off the front wing endplates move nicely around the front tyres, but then in the wind tunnel and on the track, a completely different flow pattern could be happening, and not just that the CFD results are a little less accurate!
    - CFD is limited by computing power and thus the size of the projects are limited, though of course computers just get ever more powerful! A large wind tunnel is less compromised. Also, due to the modelling complexities wind tunnels can handle complex geometries better.

    Apologies if some of this is rather dry but I hope it is of use to people. One of the great things about this site is the quality and knowledgeable discussions that go on her compared to other sites. James has done great work!

    1. James Allen says:

      Thanks for that, but please keep comments shorter in future

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