RE: Nissan powers DeltaWing Le Mans bid

[badboyburt]

Stunnimg cant wait for Lemans

[Chris71]

Speedy11 said:

Chris71 said:

You mean the nosecone alone? It's only the same as a normal open-wheeler (rather than a closed-wheel LMP), and exposed wheels are very, very draggy.

No sorry I mean it has a big sectional area some at the front and some at the back, why not have it all at the front like a normal car? A bit like an old can am

What I am trying to say is there doesn't seam to be a drag benefit from the delta wing shape, more from the lack of wings.

Good question. I'm afraid my aerodynamics knowledge ends there, but I have spoken to the designer at length in the past and I know he was very keen to get the area of the nose down. I'd swear it was an aero benefit, but maybe it's something about the ratio of front-to-rear track? Certainly, the people behind it aren't amateurs. There have been hundreds of hours simulations run on this and every single feature on the car will be there for a reason.

On a related note, check out these front wheels!

[Speedy11]

Chris71 said:

Speedy11 said:

Chris71 said:

You mean the nosecone alone? It's only the same as a normal open-wheeler (rather than a closed-wheel LMP), and exposed wheels are very, very draggy.

No sorry I mean it has a big sectional area some at the front and some at the back, why not have it all at the front like a normal car? A bit like an old can am

What I am trying to say is there doesn't seam to be a drag benefit from the delta wing shape, more from the lack of wings.

Good question. I'm afraid my aerodynamics knowledge ends there, but I have spoken to the designer at length in the past and I know he was very keen to get the area of the nose down. I'd swear it was an aero benefit, but maybe it's something about the ratio of front-to-rear track? Certainly, the people behind it aren't amateurs. There have been hundreds of hours simulations run on this and every single feature on the car will be there for a reason.

On a related note, check out these front wheels!

Please see this wonderful photoshop, not about what I mean



Surely any slight if any increase in drag would be more than offset by a better layout?

[RenesisEvo]

CBR JGWRR said:

A quick couple of lap demo with other cars and a laptimer to show it's on pace would be good.

Agreed, but given that it's running a very different weight, engine and tyres, it would be very hard to draw a comparison. Looking forward to Le Mans to see how it gets on.

[glm1977]

Balmoral said:

PascalBuyens said:

Balmoral said:

How does it not understeer like a pig? unless that is one single wheel at the front, 1200mm wide?

Think it has two wheels up front....

I was being sarcastic

With that narrow track, and LWB, how does it not go anywhere else other than straight on, in the wet? I've never seen a top fuel dragster on a GP circuit.

was written up in autosport a while back - its going to have some very clever vectoring from the back wheels (which i think will be sporting some bespoke shaped tyres), so if the theory proves correct, it should corner pretty well wet or dry.

[BSC]

Weight distribution and long leverage of front to rear makes me think of disasters that happened before, maybe not due to being in the airstream of other cars but riding over some bump. Flip.

http://www.youtube.com/watch?v=Ow3rxq7U1mA

http://www.youtube.com/watch?v=8M3NQeDzedk&fea...

Edited by BSC on Tuesday 13th March 18:03

[Killer2005]

Looks amazing

[y2blade]

Bloodyhell.....look at it!!!

[Northern Munkee]

http://deltawingracing.com/2011/06/deltawing-24-he...

I just checked with mate of mine who works in a F1 team wind tunnel and with 76% downforce bias to the rear, it ought to understeer badly. I puzzle even such weight distribution, how there is not still weight transfer back to front under braking and turning in. Of course it could corner by voodoo. It's going to awkward to pass in an lmp2 which is quick in the corners, with DW guess braking distance will be longer, then it will come flying back down the next straight.

Reading the tech specs it's stability ought not to be a problem, I'm guessing the YouTube link is to the merc gtr? That was a large flat bottom area car.

[davepoth]

Speedy11 said:

Please see this wonderful photoshop, not about what I mean



Surely any slight if any increase in drag would be more than offset by a better layout?

Define "better"?

In addition to the drag, you add weight. More weight means they wheels need to be bigger, which means the suspension needs to be beefier, which means more weight. More weight means more power, which means a bigger engine, which means more weight. I could go on, but I don't want to wear out the "w", "e", "i", "g", "h" and "t" keys.

[BSC]

Northern Munkee said:

I'm guessing the YouTube link is to the merc gtr? That was a large flat bottom area car.

Mercedes GTR Peter Dumbreck and Porsche Yannick Dalmas.

You're right, flat bottom large area, but at least there was some more weight and downforce on the front of those cars.

With less weight and rarely any downforce on the front of the deltawing vehicle I wonder what the car will do on bumpy tracks like Sebring or if the car is forced to go over the kerbs in traffic.

[TheHeretic]

Well, everyone said the GTR wouldn't work. Too little power, too heavy, etc. Let's see what they can do with this. I love innovation, and have had a hankering for some different cars, as I missed out on 6 wheel turrets, and Fan cars!

[Martin A]

CBR JGWRR said:

BarnatosGhost said:

Interesting post. I can see the 'point' in a shape like concorde, for displaying as much of the frontal area in wing format as possible, but I don't get how that translates to a car, for whom the wheels are a 'bad thing', rather than a 'good thing' like a wing.

I'm not doubting the truth of your post, I just don't quite 'get it'. Also, pushing all the weight backwards and reducing tyre size up front commensurately seems to run counter to the received wisdom of mass centralisation and 50/50 distribution.

Though the idea of fast, close racing without the mucky air of wings and downforce sounds great. Which begs the question: Why hasn't it always been done like this?

Because nobody has tried anything like it before.

But it has! http://www.vigillante.com/topgear.htm

[Hoofty]

BarnatosGhost said:

Also, pushing all the weight backwards and reducing tyre size up front commensurately seems to run counter to the received wisdom of mass centralisation and 50/50 distribution.

Received wisdom tends to forget that the 50/50 'rule' only really applies to maximising the lateral grip of a vehicle with the same tyre and track width front and back - ignoring any tractive effort.

Ever used a torque wrench? It's much easier to generate torque about an axis when your lever arm is long, isn't it? Which is precisely why this car <will> turn, because the small amount of lateral grip produced by the front axle is applied a very long way in front of the vehicle's C of G (or more accurately, its percussion centre). The underbody aero, with such a body arrangement should likely put the centre of pressure at the same point as the C of G, which is broadly what you're looking for in any racing car - regardless of what downforce generation methods you're using.

It might look a bit like it, but it isn't rocket science. Full marks to those involved for its conception, and more than that, putting it to good use after it didn't win the IRL contract.

[noell35]

I can see the batman likeness but I raise you.......

[Streps]

I really like this.
Hopefully they have a great time at Le Mans.

[Sam_68]

Am I the only one to be reminded of the Vigillante Trivette?

[anonymous-user]

BarnatosGhost said:

CBR JGWRR said:

BarnatosGhost said:

Interesting post. I can see the 'point' in a shape like concorde, for displaying as much of the frontal area in wing format as possible, but I don't get how that translates to a car, for whom the wheels are a 'bad thing', rather than a 'good thing' like a wing.

I'm not doubting the truth of your post, I just don't quite 'get it'. Also, pushing all the weight backwards and reducing tyre size up front commensurately seems to run counter to the received wisdom of mass centralisation and 50/50 distribution.

Though the idea of fast, close racing without the mucky air of wings and downforce sounds great. Which begs the question: Why hasn't it always been done like this?

Because nobody has tried anything like it before.

Thousands of the very brightest, most competitive people on the planet have spent their whole careers thinking about nothing except this very problem, and didn't come-up with this?

Do you think Adrian Newey is sitting at his breakfast table with a copy of autosport with his head in his hands - "how can I have been so stupid?"

Adrian couldn't do this even if he wanted to, F1 rules are too restrictive.

This isn't a completely new idea, the basic concept was used by Derek Gardner with the Tyrrell P34 6 wheeler. Most people think of the 6 wheeler as just that, an F1 car with 4 wheels up front and 2 at the back. But if you look at that car properly you will realise that it has a very narrow front track compared to the other cars of the period.

The basic concept of the car was to reduce the drag and lift from the front tyres and reduce the frontal area.

I've been working with the P34 recently, so did some calculations comparing it to an equivilent F1 car from that period, and one of the concerns with a narrow track is the effect of weight transfer, what i discovered is that although the P34 carries more weight up front due to the twin axles setup and it has a much narrower track, the weight transfer charicteristics were identical to a March 761 conventional 1976 F1 car, due mainly to a lower centre of gravity.

So carry this concept to a modern car like the deltawing, with its much lighter front end arangement, and the narrow track then doesn't look as bad as you may think.

The thing that killed the P34 Tyrrell off as a sucessful racing car concept was not the fact it was narrow track, it was that the front tyre technology couldn't keep up with the development of the rear tyres, so the car became unbalanced. For the last few races of the P34's life it ran a wider front track config to counter the lack of front tyre development, that increased drag and front tyre lift, so it lost it's advantages.

So, in conclusion, if the tyres are developed properly, the concept looks to have some merit. It's not the first time a smart designer has tried this in racing, but most people have forgotten what the initial concept of the P34 was about, the 6 wheels only happened after they found 2 small tyres with such a narrow track wasnt quite up to the job with the tyre technology they had at their disposal at the time.

[wst]

Apparently it doesn't need the front end grip because it's all at the back, so it only needs two tiny little wheels to turn it (think of it being like a lever with the fulcrum near the back, small force at a large distance from the fulcum = large turning moment. And it works the other way as well... a large force happening at the rear of the vehicle will have a minor effect on the front end because of the distance to the front end... of course this is a simplification where I am treating the centre of mass as a fulcrum but that's the gist I think...)

I think this thing will look like it is understeering and that the front end is 'going wide', when it's actually turning deceptively tightly. Should be good on tyres.

[PascalBuyens]

doogz said:

PascalBuyens said:

Sometimes looks can be deceiving... I suspect there to be a lot of ground effects pulling the front really down.

And looking at the front, somehow reminds me (all be it smaller) a bit of a Dodge Charger Daytona's "nose"... Still one of the most aerodynamical design to this day...

I don't doubt it'll cut through the air well. However, reducing drag doesn't increase downforce, they are 2 different things altogether.

Although, yeah, ir must have some clever ground effect design on the go under there.

Fact:
The Charger Daytona's nose made 1,200 pounds of downforce and the wing made 600 pounds of downforce.

If you look at that Deltawings front, make it a bit wider, and you have the exact same form as the '69 Daytona Charger. Efficient in both aerodynamics and downforce...