Delta wing car concept

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machin
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Re: Delta wing car concept

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for the special advance
-it can be very late brake as its friction distribution close to nature stable
-it can hard brake & turn but the front wheel won't lock up since it brake by rear, so it can transfer more load to front wheel to help turn near to the limited of tyre
To maximise braking performance of any vehicle all four wheels need to be just on the right side of locking up... any less and you are simply not using the tyres to their full potential... the delta lay-out is no different to a normal car in this respect... Any talk of "only braknig" on the rear tyres just means the braking performance is compromised.
-it can accelerate very early, stable & fast since a look like Drag car layout
Agreed. More weight over the driven wheels is good for low speed acceleration where a normal car would be traction limited. But dragsters aren't generally a good thing for race tracks as the last 100 years of automotive "natural selection" have shown. When Porsche developed the GT1 from its 911 what did they do? They took the rear-drive layout -(a layout originally developed for the VW beetle to maximise interior space), and they moved the engine forward to improve its on-track performance potential...

and when we compare it to 口 car
-you can't really lighter then Deltawing when there's are no rule & you 2 using same material & strengh are then same too, because DW a really losing a big part on front of the car.
I think the difference is much lower than you think... for example, if you were to space the front wheels out on longer suspension, and place those wheels in their own aerodynamic enclosures and make the nose correspondingly slimmer, I don't think there would much difference in weight, don't you think? I have in mind something like this:-

Image


& 口 car get more upper side area, it generate more lift force, it also making drag & neutralize some down force.
I disagree: Taking things a bit simply; if you take a wing and place it in ground effect it generates say "X"N of downforce... take the same wing and make it twice as wide and you have twice the area... so the downforce is "2.X" N -there's none of this "neutralising down force".... (although the drag is also twice as much if we neglect end-spillage effects). I believe a wider wing (representing the wider floor area that is possible with a rectangular car) is actually more efficient for a given level of downforce.. look at Gliders -their wings are wide and slender (The exact opposite of the Delta wing shape; long and narrow)....

I would love to see someone do some basic CFD studies to nail this one on the head once and for all....
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FW17
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Joined: 06 Jan 2010, 10:56

Re: Delta wing car concept

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for the special advance
-it can hard brake & turn but the front wheel won't lock up since it brake by rear, so it can transfer more load to front wheel to help turn near to the limited of tyre
Any word if they are running ABS?
I disagree: Taking things a bit simply; if you take a wing and place it in ground effect it generates say "X"N of downforce... take the same wing and make it twice as wide and you have twice the area... so the downforce is "2.X" N -there's none of this "neutralising down force".... (although the drag is also twice as much if we neglect end-spillage effects). I believe a wider wing (representing the wider floor area that is possible with a rectangular car) is actually more efficient for a given level of downforce.. look at Gliders -their wings are wide and slender (The exact opposite of the Delta wing shape; long and narrow)....

I would love to see someone do some basic CFD studies to nail this one on the head once and for all....
The purpose of the DW is to reduce drag and this is their best possible solution. A rectangular car is always going to have more drag

Scania
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Re: Delta wing car concept

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machin wrote:
To maximise braking performance of any vehicle all four wheels need to be just on the right side of locking up... any less and you are simply not using the tyres to their full potential... the delta lay-out is no different to a normal car in this respect... Any talk of "only braknig" on the rear tyres just means the braking performance is compromised.
just think
when you hard brake on stright, the front wheel nearley to lock, it won't since the it was driven by ground. when you turn the steering wheel, the force from ground to wheel reduced, brake force is the same, so the wheel lock.
on DW, less brake force on front wheel, you hard brake, the front front wheel still aren't on the top, when you turn at this moment, the drive force from ground to wheel are reduce, and the wheel will be closer to its best performance, and this is the time you need lots of grip.


machin wrote:Agreed. More weight over the driven wheels is good for low speed acceleration where a normal car would be traction limited. But dragsters aren't generally a good thing for race tracks as the last 100 years of automotive "natural selection" have shown. When Porsche developed the GT1 from its 911 what did they do? They took the rear-drive layout -(a layout originally developed for the VW beetle to maximise interior space), and they moved the engine forward to improve its on-track performance potential...
Because 911 still have same friction on front & rear wheel. when you hard brake, same brake force, same frction, but rear is heavier, so the rear wheel want to over take front because inertia.
on DW, front wheel have leser grip, the rear wheel can push the front strightly.
machin wrote: I think the difference is much lower than you think... for example, if you were to space the front wheels out on longer suspension, and place those wheels in their own aerodynamic enclosures and make the nose correspondingly slimmer, I don't think there would much difference in weight, don't you think? I have in mind something like this:-

Image
wheel cover have its area & weight, suspension have its area & weight,front wing also make Drag
machin wrote: I disagree: Taking things a bit simply; if you take a wing and place it in ground effect it generates say "X"N of downforce... take the same wing and make it twice as wide and you have twice the area... so the downforce is "2.X" N -there's none of this "neutralising down force".... (although the drag is also twice as much if we neglect end-spillage effects). I believe a wider wing (representing the wider floor area that is possible with a rectangular car) is actually more efficient for a given level of downforce.. look at Gliders -their wings are wide and slender (The exact opposite of the Delta wing shape; long and narrow)....

I would love to see someone do some basic CFD studies to nail this one on the head once and for all....
the final answer is more downforce is right
however, a surface means you are doing something with air, more surface mean you do more on it, and it means more drag, event you make it by more efficiency, you are still doing something & lose something, if the result is same, y don't we choose the lesser one? you do lesser, lose lesser, but same result.

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machin
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Re: Delta wing car concept

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on DW, less brake force on front wheel
The outright force is less on DW due to the rear weight bias, but in order to extract the most performance you stil want to be maximising the grip available from all the tyres -rectangular car or delta shaped you still want to be near 100% of the maximum braking capability or you're just simply not using all possible performance.

on DW, front wheel have leser grip, the rear wheel can push the front strightly.
As above -regardless of the shape, you still want to be using near 100% of the maximum capability, otherwise you're "wasting" performance... in addition whether the car is rectangular or delta shaped you don't want to lock the rears first...

wheel cover have its area & weight, suspension have its area & weight,front wing also make Drag
Yes... but enough to counter the negative impact of a narrow front track? - personally I don't think so, and historical evidance backs this up; dragsters are not used on circuits with corners....
however, a surface means you are doing something with air, more surface mean you do more on it, and it means more drag.
Not necessarily - take a small bluff shape such as a box.... now "add surface to it" by adding a light weight fairing to make it aerofoil shaped; the drag comes down......
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Scania
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Re: Delta wing car concept

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As above -regardless of the shape, you still want to be using near 100% of the maximum capability, otherwise you're "wasting" performance... in addition whether the car is rectangular or delta shaped you don't want to lock the rears first...
however, on 口car, you are not really using 100% of 4 tires@ the same time (if you have no EBD), 1 of axle will lose some to gain another axle's performance
& u can keep braking in the coner to gain some front grip, but you almost need to relase it on normal car
Yes... but enough to counter the negative impact of a narrow front track? - personally I don't think so, and historical evidance backs this up; dragsters are not used on circuits with corners....
before Lotus, we have 50years exprience to told us that we won't use aeroplane on circuit
Not necessarily - take a small bluff shape such as a box.... now "add surface to it" by adding a light weight fairing to make it aerofoil shaped; the drag comes down......
you can make it very low drag, you can make it very lo weight, but a "thing" must be heavier & more drag then "nothing"
your outside wheel & fairing is very light & very low drag, but it still got weight & drag

Scania
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Re: Delta wing car concept

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Scania wrote:
As above -regardless of the shape, you still want to be using near 100% of the maximum capability, otherwise you're "wasting" performance... in addition whether the car is rectangular or delta shaped you don't want to lock the rears first...
however, on 口car, you are not really using 100% of 4 tires@ the same time (if you have no EBD), 1 of axle will lose some to gain another axle's performance
& u can keep braking in the coner to gain some front grip, but you almost need to relase it on normal car
Yes... but enough to counter the negative impact of a narrow front track? - personally I don't think so, and historical evidance backs this up; dragsters are not used on circuits with corners....
before Lotus, we have 50years exprience to told us that we won't use aeroplane on circuit
Not necessarily - take a small bluff shape such as a box.... now "add surface to it" by adding a light weight fairing to make it aerofoil shaped; the drag comes down......
you can make it very low drag, you can make it very lo weight, but a "thing" must be heavier & more drag then "nothing"
your outside wheel & fairing is very light & very low drag, but it still got weight & drag
& event X2011 is not a real car, it still heavier then 500kg (545/615).

and for the Radical, lots of full size 2 seater are heavier then 520kg,
Image
this is the lightest 1 seater, but still 480kg--5kg heavier then the spec of DW, it shows it is impossible to make a car with Rectangle light like Deltawing if you need the to pass the FIA safety standed.

NoDivergence
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Re: Delta wing car concept

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The DW is going to understeer like a mofo without a wide front track. The low front track will result in little moment arm to resist the weight transfer

Jersey Tom
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Re: Delta wing car concept

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NoDivergence wrote:The low front track will result in little moment arm to resist the weight transfer
...which means the load transfer is picked up instead on the rear axle = oversteer (all other things being equal).

The weight distribution and substantially different tires front-to-rear can make the balance whatever though. All other things are far from equal.

Just wanted to pop in and clarify that subtle point. Rest of this thread is absolutely smothered in BS.
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Giblet
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Re: Delta wing car concept

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We know you know tires like few others Tom. Would love you hear your take.

Specificallyish, what if any advantage to this design can you see in comparison to a regular chassis?
Before I do anything I ask myself “Would an idiot do that?” And if the answer is yes, I do not do that thing. - Dwight Schrute

Jersey Tom
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Re: Delta wing car concept

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Giblet wrote:We know you know tires like few others Tom. Would love you hear your take.

Specificallyish, what if any advantage to this design can you see in comparison to a regular chassis?
I don't see any advantage of it, to be honest. Unfortunately have more work to do tonight so can't get into it much more... but I know I've gone over before how the claim of natural braking stability is a crock. I think that's one good example.

I'd expect one of the most awkward things to design and set up properly in this car is the differential and getting power down, with how much load will be transferred across the rear just from geometry.
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machin
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Re: Delta wing car concept

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machin wrote:As above -regardless of the shape, you still want to be using near 100% of the maximum capability, otherwise you're "wasting" performance... in addition whether the car is rectangular or delta shaped you don't want to lock the rears first...
however, on 口car, you are not really using 100% of 4 tires@ the same time (if you have no EBD), 1 of axle will lose some to gain another axle's performance
& u can keep braking in the coner to gain some front grip, but you almost need to relase it on normal car
When I say 100% I mean 100% of the grip available at the time; on a conventional car, during braking, due to load transfer there might be 70% load on the front and 30% on the rear. For a car weighing 10,000N and having a grip coefficient of 1.0 (for ease of illustration) that means you want 7,000N of braking effort on the front and 3,000N on the rear... any less on either and you're simply not usnig the full braking potential available. The same goes for Delta wing except the numbers are different; due to its static distribution under braking it might have 40% load on the fronts and 60% on the rear. For the same 10,000N and 1.0 grip coefficient that means that the braking effort on the front should be 4,000N and on the rear 6,000N... any less than that on either axle and you are simply "wasting" braking performance.. there is no "reserve" in either case. So as JT succintly puts it
the claim of natural braking stability is a crock
The radical you have used as an example has a steel spaceframe chassis and a compiste body dropped over the top... if you made a monocoque construction it would no doubt be lighter. Don't get me wrong; as I've always said -I'm sure there will be a slight weight advantage for delta wing given equal overall dimensions... but enough to counteract the reducing cornering performance? I don't think so....
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P.S.
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Re: Delta wing car concept

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Jersey Tom wrote: I don't see any advantage of it, to be honest. Unfortunately have more work to do tonight so can't get into it much more... but I know I've gone over before how the claim of natural braking stability is a crock. I think that's one good example.

I'd expect one of the most awkward things to design and set up properly in this car is the differential and getting power down, with how much load will be transferred across the rear just from geometry.
I think the deltawing design has its potential in lightweight and aero. And three wheels are even better. But I can´t arguing better than all this BS ;) So future will tell.

But I like to agree with the BS of natural braking stability! We can´t comprehend that argument in any way with the rFactor sim.

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machin
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Re: Delta wing car concept

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Scania wrote:this is the lightest 1 seater [a radical], but still 480kg--5kg heavier then the spec of DW, it shows it is impossible to make a car with Rectangle light like Deltawing if you need the to pass the FIA safety standed.
Its all about knowing where to look, :wink: Check out this bad-boy:- Just 360kg!!!!

http://www.stohr.com/html/dsr.html

Image
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Jersey Tom
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Re: Delta wing car concept

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P.S. wrote:
Jersey Tom wrote: I don't see any advantage of it, to be honest. Unfortunately have more work to do tonight so can't get into it much more... but I know I've gone over before how the claim of natural braking stability is a crock. I think that's one good example.

I'd expect one of the most awkward things to design and set up properly in this car is the differential and getting power down, with how much load will be transferred across the rear just from geometry.
I think the deltawing design has its potential in lightweight and aero. And three wheels are even better. But I can´t arguing better than all this BS ;) So future will tell.

But I like to agree with the BS of natural braking stability! We can´t comprehend that argument in any way with the rFactor sim.
I don't think you're going to necessarily get any remotely realistic results from trying to simulate this thing in rFactor.
Grip is a four letter word. All opinions are my own and not those of current or previous employers.

Scania
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Re: Delta wing car concept

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machin wrote:
Scania wrote:this is the lightest 1 seater [a radical], but still 480kg--5kg heavier then the spec of DW, it shows it is impossible to make a car with Rectangle light like Deltawing if you need the to pass the FIA safety standed.
Its all about knowing where to look, :wink: Check out this bad-boy:- Just 360kg!!!!

http://www.stohr.com/html/dsr.html

Image
does it got LMP1 performance & safety standed?