RE: DeltaWinging it with Nissan at Le Mans

[redstu]

I liked it a lot! Still fast but with the smallest engine and least power , mean looking. Hope there are more wack racers next year.

[Ferritboy]

I was so upset when they dropped out the race, i was in the grandstand right opposite their garage, i became quite attached to the Delta Wing.

[phaworth]

Autosport carried the story this week that it might be allowed to compete as is in the ALMS, which would be fantastic.

Additionally, it said that Deltawing Racing Cars are considering offering customer LMP1 and LMP2 variants of this base spec; they'd have to make several tweaks I expect to make it compliant with the specific LMP regs, but how hard can that be? Hopefully, we'll see perhaps more than one running next year... And hopefully with a lot more development running under their belts by then.

[Numeric]

Please don't laugh at this question - it is from an engineering noodle - but if the thing was so efficient in its running - what would have happened if it was running an engine of greater power? Would it then have been a front runner? Or is this one of those funny aerodynamic things where to go a little faster takes double the power even with the clever design? I guess I'm asking what the potential limit would be if you went with 400hp or something? Also is this a better design - I mean should all LM cars look like this?

Edited by Numeric on Tuesday 19th June 16:00

[fatboy69]

No. All LM cars should look like either a Porsche 962, a Sauber/Mercedes, a Lancia LC2 or a Jaguar XJR9.

Not forgetting a few Porsche 917s, 934s, 935s & the Ferrari 512s.

Nothing else should be allowed to enter Le Mans. IMO anyway.

Daft response i know however i want to see proper race cars at LM & not the Audi's that dominate every year.

Have you heard the noise from the Group C cars as they hurtled down the Mulsanne during their race?

Sublime. Compare these beasts to the noise, or lack of, from the current breed of LM car.

[Jenx]

Nakajima is a prize cock! I really feel for Marino.

There was real dissapointment on the grass banking at Tetre Rouge...all nationallities were gueninely disappointed (and pissed at Nakajima) when it got punted off.

It will be a crying shame if this car is not developed further.

[Luca Brasi]

Impressive effort by Nissan. Car looks rather ridiculous though.

[Naithan]

me and my lads (all 30 of us) cheered every lap it went past, it was a heroic entry. the ACO angered me not allowing it to continue, hell who were the buggers affecting?

the vid of the lad trying to fix the poor heap filled me up.

highcroft and nissan played a blinder... saying that Toyotas actions afterwards deserve commending too.

god lemans was amazing this year...

[phaworth]

Numeric said:

Please don't laugh at this question - it is from an engineering noodle - but if the thing was so efficient in its running - what would have happened if it was running an engine of greater power? Would it then have been a front runner? Or is this one of those funny aerodynamic things where to go a little faster takes double the power even with the clever design? I guess I'm asking what the potential limit would be if you went with 400hp or something? Also is this a better design - I mean should all LM cars look like this?

In short, a more powerful engine would certainly make it go faster, yes.

Technical bit (deep breath...): Due to its delta design, it has a lack of traditional wings or splitters of any description (all downforce is generated underbody), so it is a very slippery shape with little drag (coefficient of Cd0.24 - compare to the be-winged Audi's Cd0.47). Combined with appropriate gearing and a powerful enough engine (power required to push an object through a fluid (air) increases as the cube of velocity), it should be able to attain relatively high speeds through the speed traps and, crucially, get to those speeds quickly too. For evidence of this, just watch the TOCA series and see how a downforce laden Ginetta G55 struggles out of the slow bends to out accelerate the older, less powerful but more slippery G50. Ultimately over 1 lap, the G55 is quicker obviously, but the performance differential is a lot closer in a drag race.

The Audi generates HUGE amounts of downforce, particularly at the front, which punishes its theoretical vmax. Last year, for example, it topped out at 206mph versus the Peugeot's 212mph. The Deltawing is likely to generate significantly less downforce than a traditional LMP car, but efficiencies elsewhere would hopefully make up for this.

I don't think LMP cars, under the current regulations, could look like it. It's very prescriptive about a lot of things - the mandated sharkfin air dam, for example, designed to stop the car flipping when it gets to a critical yaw angle (Ahem - ACO shuffles its feet uncomfortably in front of Anthony Davidson's wrecked Toyota...). So it would take a change in the regs (as ALMS is proposing) to allow it to compete directly.

I don't think it's a "better" design, but it's certainly more efficient and certainly original and cutting edge. The narrow track and tyres at the front, for example, will probably mean that its wet weather grip is likely to be charitably described as "terrifying"...

Huge thumbs up from me though. Bring on the LMP1 version...

[mrmr96]

TonyHetherington said:

It drove around a track at the same time as a race was on, but that was all. It was car number '0', in no class.

I don't think it was "no class" I thought it was in the "experimental class"? (Just that it was the only one in it's class.)

[ukcobra]

Was very disappointing that they were not able to repair it and get back on track.
I was watching when it got taken out by the Toyota and a bunch of us were gutted.

What was interesting was how many people stood up and went to take pictures near the start when it came into position at the start, it certainly grabbed a lot of attention.

I personally would have liked it to have got to the finish.

[chrisjl]

phaworth said:

It's very prescriptive about a lot of things - the mandated sharkfin air dam, for example, designed to stop the car flipping when it gets to a critical yaw angle (Ahem - ACO shuffles its feet uncomfortably in front of Anthony Davidson's wrecked Toyota...). So it would take a change in the regs (as ALMS is proposing) to allow it to compete directly.

I would say the presence of the sharkfin is the very reason Ant left the ground. Is the thinking was that the fin would encourage a car with a significant amount of yaw to tend to straighten up, and therefore increase the driver's chance of saving it? If so, not enough analysis was done on the other effects. With the car travelling at 90 degrees to the way it's pointing, that huge amount of drag very high up is what lifted the right-side wheels and allowed air to get under the car.

[//j17]

chrisjl said:

I would say the presence of the sharkfin is the very reason Ant left the ground. Is the thinking was that the fin would encourage a car with a significant amount of yaw to tend to straighten up, and therefore increase the driver's chance of saving it?

The idea is that, if a car goes sideways it's still got forward momentum but now has some sticky rubber trying to stop the bottom of the car. If these catch at all the car naturally barrel rolls, clockwise if looking at the front of the car.
The fin was added as a bloody great air-brake, so while you still have the tyres at the bottom trying to grip and rotate the car clockwise you now have a sail catching the air and trying to make it roll anti-clockwise.

Now in Davidson's case he was impatient and took on an overtake that should have waited till after the corner the tyres didn't grip but the fin did it's job - it provided an anti-clockwise rotational force...without a clockwise one to counter...so the car rolled the other way!

[rdjohn]

I thought the fin did its job really well.

The car was straightened and hit the barrier head on where the crash protection and HANS can do their job best.

The other car continued to slide sideways and hit the barrier hard with semmingly greater force.

A good dose of luck also helped both drivers.

[phaworth]

rdjohn said:

The other car continued to slide sideways and hit the barrier hard with semmingly greater force.

A good dose of luck also helped both drivers.

Yes - it was a frightful incident and thank goodness both escaped more serious injury.

Just compare how much the tyre barrier moved with his impact compared to Davidsons (especially on the overhead shot) and how all that energy turned into vertical lift on impact... More mass, less aero accoutrements = bigger impact...

Scary stuff. Wouldn't have fancied being in either.

[chrisjl]

//j17 said:

chrisjl said:

I would say the presence of the sharkfin is the very reason Ant left the ground. Is the thinking was that the fin would encourage a car with a significant amount of yaw to tend to straighten up, and therefore increase the driver's chance of saving it?

The idea is that, if a car goes sideways it's still got forward momentum but now has some sticky rubber trying to stop the bottom of the car. If these catch at all the car naturally barrel rolls, clockwise if looking at the front of the car.
The fin was added as a bloody great air-brake, so while you still have the tyres at the bottom trying to grip and rotate the car clockwise you now have a sail catching the air and trying to make it roll anti-clockwise.

Now in Davidson's case he was impatient and took on an overtake that should have waited till after the corner the tyres didn't grip but the fin did it's job - it provided an anti-clockwise rotational force...without a clockwise one to counter...so the car rolled the other way!

I think you've got clockwise and anti-clockwise the wrong way around, but otherwise I agree with the presence of those two forces acting on the car. The only problem is the huge discrepency between them, and the fact that it gets worse at higher speeds. A tyre that's in a pure slide doesn't generate a great deal of friction (but it gets better as the speed drops?). An aero device generates vastly higher forces as speed increases. When the fin induced torque (about a line through the contact patches of the left tyres) exceeded the combined mass and friction induced torque in the opposite direction the car was off the kerbs and on a flat bit of track, so even with everything in their favour, the tyres couldn't cancel the fin drag. As for how much speed it shed - a lot of that would have been in the tumbling through the air phase, when the greatest area was being presented in the direction of travel.

[mko9]

Much ado about nothing, as it is not comparable to any other car in any race series. It was essentially a back marker LMP2 car while weighing hundreds of kilos less. Build an LMP2 car to 475kg instead of 900kg, and see how much faster it would be than that atrocity.

[HowMuchLonger]

mko9 said:

Much ado about nothing, as it is not comparable to any other car in any race series. It was essentially a back marker LMP2 car while weighing hundreds of kilos less. Build an LMP2 car to 475kg instead of 900kg, and see how much faster it would be than that atrocity.

Using your obvious skills you could explain to Audi how to cut the weight of their cars by 50%. They would be very grateful, since they are obviously wasting their money developing their winning cars when you could come along and cut the weight just like that.

[jimroyale]

Nice to see the delta wing in action last weekend. Also the replica driving past. Trying something differeren should be encouraged. The audis were impressive but very boring. The pistonheads write up is p155 poor. My ten year old daughter can write with far fewer errors than that. Was the authour smashed at the time, like me in a field in France?

[SCRR]

mko9 said:

... that atrocity.

You complete tit.