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Deltawing for LeMans in 2012


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#151 Slowinfastout

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Posted 23 March 2012 - 16:00

@saudoso, the deltawing is already only 10 seconds off the Audi LMP1 at Sebring with some crucial systems on the car not working/sorted/being used yet.. I think it's fair to say the concept works and is already properly fast.

It will be interesting to hear about tires in an endurance setting though.

Edited by Slowinfastout, 23 March 2012 - 16:03.


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#152 Ross Stonefeld

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Posted 23 March 2012 - 16:03

If they made this the LMP2 rules package I might pay attention to that part of the series.

#153 saudoso

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Posted 23 March 2012 - 16:32

@saudoso, the deltawing is already only 10 seconds off the Audi LMP1 at Sebring with some crucial systems on the car not working/sorted/being used yet.. I think it's fair to say the concept works and is already properly fast.

It will be interesting to hear about tires in an endurance setting though.



I'll wait until the race, and then what happens when the handicaps are pulled out to be sure. But yes, I'm feeling a bit silly right now

#154 bigleagueslider

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Posted 24 March 2012 - 05:18

The word from a Nissan GT Academy participant was the Delta Wing looked really good at Sebring and had no problems keeping up with other cars. What "other cars" means I haven't been able to suss out. Rumor is after LeMans they are going to bring the car back to the US and do ALMS. Road America ticket sales person was saying it had a good chance of being there. I hope it hits objectives in LeMans so we can see it here.


The Delta Wing has much less power than other P cars. But it claims to make up the difference with less weight and less drag.

I can't believe the Delta Wing ran competitive times at Sebring. Sebring is a bumpy track and it would not seem to suit a car with 4-inch wide front tires, a narrow front track, and little front grip.

The 24 hour LeMans race however, is a different story. The track is smoother and more wide open. The Delta Wing will need fewer pit stops, and will be easier on tires, transmission, and brakes.

#155 cheapracer

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Posted 24 March 2012 - 05:39

it would not seem to suit a car with 4-inch wide front tires, a narrow front track, and little front grip.


And how do Karts go around corners I wonder (and faster than most racing cars) ....

Many aren't connecting with the fact that it is 475 kilograms compared to 900 kilograms for the cars it's competing against.

Best technical views so far ..



#156 cheapracer

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Posted 24 March 2012 - 05:40

It has 4 wheels.


5 with the steering wheel, but you know what I meant.

Actually under most motor vehicle codes (mostly applies to trucks), the spacing between the 2 front wheels is one wheel.

The BMW Bubble car was legally a 3 wheeler for example.

#157 RDV

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Posted 06 June 2012 - 22:10

Franchitti/Krumm/Motoyama Highcroft Delta Wing Nissan 3m47.980s
How now, brown cow? :lol:

#158 Mark A

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Posted 15 June 2012 - 06:20

After final qualifying session

29. Franchitti/Krumm/Motoyama Highcroft Racing DeltaWing Nissan 3mins 42.612secs

#159 desmo

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Posted 15 June 2012 - 13:10

Impressive time in spite of some issues with the onboard fire extinguisher system. Puts them squarely bracketed in the LMP2 times, with half again as much bhp.

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#160 BRG

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Posted 15 June 2012 - 16:17

Puts them squarely bracketed in the LMP2 times, with half again as much bhp.

Not to mention twice as much weight. And a lot less downforce. So really no comparison can be made.

Hearing the bloke from Nissan being interviewed on Eurosport made me think that (although naturally he didn't say as much) that Nissan are using this as is a publicity gimmick. It is being used in their TV adverts, whereas none of the real LMP cars with Nissan power are featured. Although they are mostly quicker than the D'wing. This is a pointless freak-show, a technological dead-end.

Edited by BRG, 15 June 2012 - 16:18.


#161 sblick

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Posted 15 June 2012 - 21:02

Not to mention twice as much weight. And a lot less downforce. So really no comparison can be made.

Hearing the bloke from Nissan being interviewed on Eurosport made me think that (although naturally he didn't say as much) that Nissan are using this as is a publicity gimmick. It is being used in their TV adverts, whereas none of the real LMP cars with Nissan power are featured. Although they are mostly quicker than the D'wing. This is a pointless freak-show, a technological dead-end.

Running around in a car that uses 300 Hp to overcome its "wings" and gets 2 miles per gallon is just as pointless. An LMP2 car is proving nothing to me other than engineers thinking in the same box. It is a useful exercise for the ACO to determine possible rule changes to make the LMP2 racing cars different and possibly more relevant. I would think it is more relevant to run a more aerodynamically slippery car that gets 6 mpg than running around in a brick that gets 2 mpg. And holy cow Nissan is using this as a publicity/marketing exercise!!! Wake up, all of racing at a manufacturers level is a publicity/marketing exercise. Except maybe just maybe some F1 work. Sorry rant over.

#162 desmo

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Posted 15 June 2012 - 21:18

One could just as easily characterize F1 as "pointless freak-show, a technological dead-end" albeit a better financed and attended one.

#163 Magoo

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Posted 15 June 2012 - 21:38

At this point in the evolution of the sport, I think people are willing to cut a considerable amount of slack to anything that is new and different and interesting.

I don't know what is so horrible about the Deltawing being a publicity stunt. Professional motorsports is a publicity stunt. What desmo said.

#164 Wolf

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Posted 15 June 2012 - 22:53

Magoo- maybe what you said is agreement with Desmo*, and maybe it isn't... :p I think the trouble with Deltawing project is that they're allowed, sort of, to work outside the regulations- but (being biased by British media) I'm willing to concede that ACO is willing to make Le Mans rules suit their agenda. Novetly or not, what are the chances of Deltawing being a success if it was to conform to either LMP1 or LMP2 rules? I'm not entirely convinced by this recent trend towards 'private effort'- be it CRT in MotoGP or this Deltawing in LMP2 class; to me it reeks as publicity stunt to attract 'cannon fodder' to a certain racing class in order to bring up the numbers or attract some media attention (read: entertainment value) without adding anything worthwhile to the racing effort.

* as a pointless aside, I was quite amused (if not exactly surprised) to see, to the best of my knowledge, earliest known date of automotive desmodromic valve actuation being pushed back to 1914 :D at least, when GP racing is concerned ;)

#165 Magoo

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Posted 15 June 2012 - 23:47

What we have here is a faint callback to the earliest days of the sport. When this whole thing called auto racing began, there were often entries that were a poor fit for the existing rules or organization. This was not seen as a shortcoming of the cars but as an oversight of the organization. Ways were found to accommodate these competitors for the good of the sport, the audience, the competitors, and the industry. And it was good for everyone. Racing suffers today for its extremely formalist structure.

#166 mariner

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Posted 16 June 2012 - 10:01

IIRC Bowlby has had a long record of skilled self promotion. I am not entirely sure of his background but I think he studied engineering in uk. He certainly got himself on a UK tv program about " young engineers with new ideas" long ago.

That not being snide or critical. I think he realises that self promotion is the way to fund your ideas and those ideas have to be shaped to fit commercial reality.

In a way thats not so different from a person like Colin Chapman whose success with new ideas was helped a lot by his self promotion and "selling" of his dreams . In contrast many people with radical ideas are too shy to ever get funding.

I'm not sure if the delta wing wil ever work under equal terms ( ie weight , tyre size etc. ) but all the best to Bowlby for getting something so radical to Le Mans .

The whole exercise raises an interesting question about weight BTW.

Every formula now has a minimum weight for "safety" . At the same time people say racing must become " greener". The big point being made for this car is its low weight.

So if the delta wing can ( roughly ) match cars twice the weight and be under 500kg why do all racing formulae have to have minimum weights when less weight is the best way to save fuel in the real world.

Think about it , Le Mans has regs for everything but it allows a car of half its own minimum weight rules to go on the track with other cars AND spectators present. Makes a mockery of minimum weight for "safety"

Edited by mariner, 16 June 2012 - 10:04.


#167 Ross Stonefeld

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Posted 16 June 2012 - 11:40

A socially adjusted engineer, what? :p

#168 Tony Matthews

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Posted 16 June 2012 - 11:53

I seem to remember that much was made of Ben Bowlby's dyslexia when he started working at Lola. Quite rightly, the point was made that it bears no relationship to intelligence, but I think it may have kick-started his 'notoriety', and if he has added to this with self promotion, good luck to him!

#169 BRG

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Posted 16 June 2012 - 14:42

One could just as easily characterize F1 as "pointless freak-show, a technological dead-end" albeit a better financed and attended one.

I agree, but at least there are 24 dead-ends on the grid, built to the same rules. The simple facts are that if you built a conventional four wheel car weighing the same as the D'wing (such as a Radical for instance), using the same engine, it would be substantially faster then the freak-show and for the same fuel consumption. So what exactly is the point? What is the D'wing proving? What is the new technology that it is experimenting with?

Nothing, nada, rien.

Watching it wobble around Le Mans like an oversized motorcycle side-car rig is just rather sad.

#170 Magoo

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Posted 16 June 2012 - 16:36

I don't think the narrow front track concept is ultimately competitive myself, but I don't understand how the project inspires such bitter responses. Let's get Danica to drive it so the Haters can really enjoy themselves.

#171 Powersteer

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Posted 16 June 2012 - 19:15

The car is not slow for sure..

:cool:

#172 saudoso

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Posted 16 June 2012 - 23:57

All the rearward weight bias proven really good for race card dynamics.

Edited by saudoso, 16 June 2012 - 23:59.


#173 Ross Stonefeld

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Posted 17 June 2012 - 17:39

How did you miss the part where the Toyota swerves into him?

#174 Ali_G

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Posted 17 June 2012 - 17:42

How did you miss the part where the Toyota swerves into him?


:lol:

This is what happens when a car, twice the weight of yours hits you. Was incredibly careless by Nakajima.

#175 WhiteBlue

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Posted 17 June 2012 - 17:50

The deltawing concept has a lot to go for. This race showed the potential and proved the concept. I hope that more will follow.

#176 Slowinfastout

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Posted 17 June 2012 - 18:09

I agree, but at least there are 24 dead-ends on the grid, built to the same rules. The simple facts are that if you built a conventional four wheel car weighing the same as the D'wing (such as a Radical for instance), using the same engine, it would be substantially faster then the freak-show and for the same fuel consumption. So what exactly is the point? What is the D'wing proving? What is the new technology that it is experimenting with?

Nothing, nada, rien.

Watching it wobble around Le Mans like an oversized motorcycle side-car rig is just rather sad.


For example, F1 has regulation that enforces a specific weight distribution.. 46:54

A Radical SR8 is 41:59 while the Deltawing is a mental 28:72.. it is a completely different car and its configuration is carefully calculated to work. Plus I have not seen anyone apart from armchair forum experts being able to counter Bowlby's claim that the reduced frontal area is a significant gain for the Deltawing design.

As soon as you bring the weight forward and you widen up the front track, you need bigger front tires and slowly but surely you lose this advantage the Deltawing has, so you'll need a bigger engine to push this around.

For those reasons I doubt a Radical would get anywhere near the fuel consumption of the Deltawing if it was using its engine, and it would also be slower I bet.

Edited by Slowinfastout, 17 June 2012 - 18:10.


#177 Ali_G

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Posted 17 June 2012 - 18:28

The deltawing concept has a lot to go for. This race showed the potential and proved the concept. I hope that more will follow.


But what should come out of it.

I sincerely doubt a new LeMans class will be established for it. I doubt a racing series using spec Deltawings would last too long. A curiosity at first but after that.....

#178 h4887

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Posted 17 June 2012 - 19:13

At this point in the evolution of the sport, I think people are willing to cut a considerable amount of slack to anything that is new and different and interesting.

I don't know what is so horrible about the Deltawing being a publicity stunt. Professional motorsports is a publicity stunt. What desmo said.


After all, there is a precedent - in 1963/5 they made room for the Rover-BRM gas turbines...

#179 BRG

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Posted 17 June 2012 - 19:47

Plus I have not seen anyone apart from armchair forum experts being able to counter Bowlby's claim that the reduced frontal area is a significant gain for the Deltawing design.

Apart from every other race car designer in history, you mean?

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#180 Slowinfastout

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Posted 17 June 2012 - 20:03

Apart from every other race car designer in history, you mean?


Link?

#181 BRG

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Posted 17 June 2012 - 20:32

Link?

Don't be obtuse. You know that I meant that if it was such a wonderful and innovative idea, it would have been tried long ago.

#182 Ali_G

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Posted 17 June 2012 - 21:13

I can't see why it would be aerodynamically superior to a car having the same width all the way to the front.

The only advantage IMO that the car would have is less frictional drag from having less surface area exposed to air flow. The air passing over the car still has to deal with the wide part of the car at the rear which would create similar amounts of drag if the car was this width all the way from front to back.

I would imagine that the advantages of superior stability, more surface area to generate downforce and a more even weight distribution between both axles would mean a standard layout would be faster. I doubt drag really comes into it at all.


What the logic behind the deltawing producing less drag than a rectangular car ?

#183 Greg Locock

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Posted 17 June 2012 - 22:16

I can't see why it would be aerodynamically superior to a car having the same width all the way to the front.

What the logic behind the deltawing producing less drag than a rectangular car ?

Dunno, but it is almost irrelevant. Most of the drag produced by an open wheeler is to do with generating lift and wheels and suspension and so on, the actual fuselage is a small proportion.

#184 Slowinfastout

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Posted 17 June 2012 - 22:25

This is pulled from the Highcroft website:

Vehicle weight distribution is necessarily more rearward than traditionally seen with 72.5% of the mass between the wide track larger rear tires.

76% of the aerodynamic downforce acts on the rear of the car which has a lift to drag ratio of >5.0.

Rear wheel drive coupled with the rearward weight and aerodynamic distributions greatly enhances inline acceleration capability.

Unique amongst today’s racing cars, more than 50% of the vehicle’s braking force is generated behind the center of gravity giving a dynamically stable response.

Locking propensity of the un-laden front wheel at corner entry is greatly reduced due to virtually no lateral load transfer with the narrow front track/wide rear track layout, steered wheel “scrub drag” moment is virtually zero greatly increasing tire utilization and reducing mid turn understeer.


There is stuff in there that a 'square' car can't match.. I guess it remains to be seen if this is a pointless exercise but personally I don't think it is.. it's definitely different and not just for the purpose of being different, which would be fine with me anyway, lol

#185 Ali_G

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Posted 17 June 2012 - 23:24

This is pulled from the Highcroft website:

Vehicle weight distribution is necessarily more rearward than traditionally seen with 72.5% of the mass between the wide track larger rear tires.

76% of the aerodynamic downforce acts on the rear of the car which has a lift to drag ratio of >5.0.

Rear wheel drive coupled with the rearward weight and aerodynamic distributions greatly enhances inline acceleration capability.

Unique amongst today’s racing cars, more than 50% of the vehicle’s braking force is generated behind the center of gravity giving a dynamically stable response.

Locking propensity of the un-laden front wheel at corner entry is greatly reduced due to virtually no lateral load transfer with the narrow front track/wide rear track layout, steered wheel “scrub drag” moment is virtually zero greatly increasing tire utilization and reducing mid turn understeer.


There is stuff in there that a 'square' car can't match.. I guess it remains to be seen if this is a pointless exercise but personally I don't think it is.. it's definitely different and not just for the purpose of being different, which would be fine with me anyway, lol


A lot of that does make sense.

Not sure about any aerodynamic advantage though. Were Highcroft banging on about that in interviews or something ?

#186 Canuck

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Posted 18 June 2012 - 01:31

I meant that if it was such a wonderful and innovative idea, it would have been tried long ago.

Make sure to colour inside the lines that someone else made for you. That's the path to innovation - following the leaders.

I despise that excuse and the arrogant thought process behind it, especially in myself. Sure, not everything that hasn't been tried is worth pursuing, but not having been tried before doesn't preclude something from having potential.

#187 mariner

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Posted 18 June 2012 - 08:55

The delta wing has now raced so well done to them.

whilst the idea of racing a three wheeler ( in effect) against four wheel cars is very novel I don't think the rest of the car is that extreme or new.

Going back the Lotus 72 , which was mega successful, had a strong rear weight bias, probably near 30/70 unladen. In its 72D form it had an extreme rearward aero balance because the big rear wing was extended out by an extra 10" to get more rear grip. It also had a quite narow front track so a lot of the roll stiffness was in the rear end.

http://world-viewer....os/lotus-72/04/

Tony Southgates BRM P180 was also designed to have 70% rear bias. Oddly despite using the std. F1 tyre sizes of the day it apparently understeered more than the previous , more conventional car.

http://www.ultimatec...RM-P180-_3.html

The deltawing team say the car has 28/72 rear bias

Also weight distributions are usually not as extreme as quoted because the quoted ones are unladen and once you put the driver and fuel in things tend to move back towards 50/50 so maybe not too much should be read into ratios more biased than 30/70.

I also dont think Dan Gurney will be that surprised by the aero design. THe Deltawing team openly admit they used the aero design of the 1981 Eagle Indy car which IIRC got onto the front row at indy
. A quote from that cars' designer " the vorticity off the triangular plan forms along the sides of the tub, sorts of rolls itself up into an ever increasing hollow tunnel , if you will, underneath. It was very powerful - very pitch sensitive, but very powerful.

see pic. here

http://www.flickr.co...ges/5121044480/

The delta car team now call that BLAT Boundary Layer adhesion technolgy.

The key claim to " novelty " to use the the Patent term seems to be streamlining the front wheels by moving them inside a single seater type nose. clearly that should improve airflow to the rear aero region but in terms of results , as opposed to pure novelty, you could only judge the Deltawing cars sucess if you matched it against single seaters with carefuly faired in wheels - which isnt allowed !



Lastly the engine is claimed to develop only 300bhp. the car is claimed to weigh 450kg. A LM proto has a minimum weight of 900kg and is limited to about 550 bhp or so. Therefore the unladen power to weght ratios are similar at 660 bhp/tonne IF the engine really has only 300 bhp. If I had one " suspicion" about the whole project it would be what the real power level is given its not running , as far as I know, to any specific restrictor rules. The engine could easly put out 600 bhp and, being cynical for a moment, the intercooler size looks bigger than 300 bhp's worth in the photos.

#188 Magoo

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Posted 18 June 2012 - 10:27

:lol:

This is what happens when a car, twice the weight of yours hits you. Was incredibly careless by Nakajima.


Or, why it doesn't pay to get too excited about these developments. Sometimes things take care of themselves.


#189 saudoso

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Posted 18 June 2012 - 11:29

How did you miss the part where the Toyota swerves into him?


No I didn't. And the DW did get knocked out of the track like it had been hit in the jaw by a 800 pound gorilla.

And after that it seemed like the steering linkage was broken. No correction movement at all, straight to the wall.


Plus I have not seen anyone apart from armchair forum experts being able to counter Bowlby's claim that the reduced frontal area is a significant gain for the Deltawing design.


You see, the deltawing shape does not reduce frontal area. It does have a long nose and the profile is thin up to the end of the cockpit, but you can get the exact same frontal area with a square car. If you cut some team the same slack the DW had you can rest assured it would be a very, very nice car.

IMO the great thing it showed is how a weight reduction makes a huge difference. In fuel consumption specifically. Something I've been repeating to the walls for a long time around here.

Edited by saudoso, 18 June 2012 - 11:30.


#190 Slowinfastout

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Posted 18 June 2012 - 12:51

Ok so the only reason this car was able to perform is because some slack was cut...

There's no need to go at each other's throats over this, let's see how that passes the smell test over time..

#191 saudoso

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Posted 18 June 2012 - 14:30

OK.

I'm one of the most vocals against it from the beginning. Got my piece of humble pie.

But.

I still don't believe it's race track worthy. Not maximizing the foot print is not a good idea. So they managed to make it run. Right. But the first time it was touched by something it went off like a slot car.

Now imagine if Indycar had bet the farm on it and these things started going for the wall without a chance of correction every time something went wrong.

Edited by saudoso, 18 June 2012 - 14:30.


#192 Rob

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Posted 18 June 2012 - 16:23

I still don't believe it's race track worthy. Not maximizing the foot print is not a good idea. So they managed to make it run. Right. But the first time it was touched by something it went off like a slot car.


Why is it better to maximise a car's footprint? Surely it's better to minimise it for the aero gain?

Don't forget, Nakajima's car was heavier. At the point that Nakajima's car was no longer in contact with the DeltaWing, the DeltaWing was more than 50% on the grass. Any car would struggle in that scenario.

#193 BRG

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Posted 18 June 2012 - 16:56

Now imagine if Indycar had bet the farm on it and these things started going for the wall without a chance of correction every time something went wrong.

That's the thought that struck me too, watching the D'wing on track. It never looked very planted - it seemed to be twitchy compared to the other cars. The idea of 20 or 30 of them, with more power, on a high-speed oval sounds like a short cut to Armageddon. Maybe Indycar have had a lucky escape.

#194 saudoso

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Posted 18 June 2012 - 19:40

Why is it better to maximise a car's footprint? Surely it's better to minimise it for the aero gain?

Don't forget, Nakajima's car was heavier. At the point that Nakajima's car was no longer in contact with the DeltaWing, the DeltaWing was more than 50% on the grass. Any car would struggle in that scenario.



footprint <> frontal area

#195 Rob

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Posted 18 June 2012 - 21:43

footprint <> frontal area


No, but they are not independent.

#196 saudoso

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Posted 18 June 2012 - 23:19

If you keep the rear end section the same, having the fromt wheels 50cm or 2m apart can have zero impact on frontal area. In fact, the longer cross sections* of the square car deliver lower CDs for the same frontal area.

That's not sourcery, with free rules you can create a square car at least as aerodinamically effective as the DW. The only down side is the width of the front wheels. The DW has no other granted advantage over a square car in aero.

*chord length is the correct english term?

Edited by saudoso, 18 June 2012 - 23:21.


#197 WhiteBlue

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Posted 19 June 2012 - 02:22

....with free rules you can create a square car at least as aerodinamically effective as the DW.

The DW has no other granted advantage over a square car in aero.


I wonder how people now all these things without any modelling and CFD computations. Seat of the pants aerodynamics?


#198 saudoso

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Posted 19 June 2012 - 02:32

I wonder how people now all these things without any modelling and CFD computations. Seat of the pants aerodynamics?



It might sound weird to you, but I actually ran all that stuff by hand in my university years. Calculated with an HP 48 calculator and dragged model boats along 300 meter long test tanks. We even assembled our own strain gates. And we could see how the chord length and frontal area affect the flow around an object.

When you do it like that, you actually learn stuff and can figure things out. You must keep in mind that someone does know more than the CDF programs in order to be able to design them.

Edited by saudoso, 19 June 2012 - 02:33.


#199 Kelpiecross

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Posted 19 June 2012 - 04:19


Nobody seems to have mentioned the fact that just before the DW's crash the other cars were passing it around the outside of the corner as if it was standing still.
If the DW did not slow on purpose to let the faster cars through it didn't have much corner speed at all. A conventional 450kg car probably would be faster through those curves than the bigger 900kg cars.
I suspect Nakajima hit it because he didn't expect to come across something so slow.


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#200 RDV

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Posted 19 June 2012 - 06:52

K-Nobody seems to have mentioned the fact that just before the DW's crash the other cars were passing it around the outside of the corner as if it was standing still.

Car was coming in to change driver after the safetycar period finished, as did 12 other cars. In this case you don't hold up others. Nakajima has previous form in incidents like this. Re acceleration and front wheels= consider the standard LMP 24kg per wheel against 7kg for the DW in rotational inertia, there is a notable advantage inacceleration, despite lower power.