Dome's F20 series

[flynfrog]

Slim,

This type of vortex tube: http://en.wikipedia.org/wiki/Vortex_tube

And any exhaust turbocharger should suffice. After speaking directly to the manufacturer, their 3/4 inch model (19.5mm) will push 33cfm at max, but that can be increased by driving multiple tubes into an intake header, or manifold.

If someone has one of these engines, and live anywhere close to me, I have a manufacturer willing to send me 3 of them for a 90 day trial.

Slim, with that 9.9 number, does the temperature/density of the air matter? And can it be forcefed under pressure if the temp is way low.. (-30C).

Thanks!

Vortex tubes have lower efficiency than traditional air conditioning equipment. They are commonly used for inexpensive spot cooling, when compressed air is available. Commercial models are designed for industrial applications to produce a temperature drop of about 45 °C (80 °F).

so even well made units are not that good not to mention that they probably dont like the harmonics of piston engine. 80F isn't going to give much of power boost not to mention the weight and complexity this would add to a race car.

As they say in thermo there is no free lunch

[Scania]

20mm restrictor is tiny!

My Formula Student car is running a 38mm restrictor (IIRC) and that's on a 0.55 litre engine...seriously, a 20mm restrictor will reduce possible mass flow rate to virtually nothing!

I rember that FSAE rule should be 20mm(Gasoline) or 19mm(E85).....

[Scania]

but... how about if I don't use engine?

[freedom_honda]

correct me if im wrong.
but what is the point of having an open-wheeler without any wings that produces downforce?
the exposed wheel creates a massive amount of drag, while the other two designs dont. so what exactly are the advantages of having an open wheeler? (assuming their minimum weight is the same)

[Scania]

1.this cars is not fast
2.they got wings....
3.there are no any rule about aerodynamics

[Roland Ehnström]

correct me if im wrong.
but what is the point of having an open-wheeler without any wings that produces downforce?
the exposed wheel creates a massive amount of downforce*, while the other two designs dont. so what exactly are the advantages of having an open wheeler? (assuming their minimum weight is the same)

* = you mean drag here I presume.

I also can't see any good reason to go for an open-wheeler, as the exposed wheels surely produce a massive amount of drag for no obvious gain. But maybe it's good to have the weight centered as much as possible, and maybe the minimum weight in this series is so low that it is nearly impossible to reach it if you have a full bodywork? Remember that in the 50's, when streamliners were still allowed in formula one, they were actually only used on tracks like Monza, Avus or Reims. Everywhere else, they always went for exposed wheels. On the other hand they used very slim tires in those days, so the disadvantage of exposed wheels was much lower than today. Edit: It seems these cars have rather skinny tires too, so maybe the disadvantage of having exposted wheels is not that great.

[Jersey Tom]

Exposed wheels do create lift and drag. You can get a ballpark for those numbers easily if you reference RCVD. Bear in mind though, by going with a close-wheel car you just as easily really increase the frontal area of the vehicle...

[freedom_honda]

1.this cars is not fast
2.they got wings....
3.there are no any rule about aerodynamics

1. If those cars do have such small engines with so little power, every bit helps.
2. Well as far as i can see those wings have minimal angle of attack i doubt they even produce any downforce.

correct me if im wrong.
but what is the point of having an open-wheeler without any wings that produces downforce?
the exposed wheel creates a massive amount of downforce*, while the other two designs dont. so what exactly are the advantages of having an open wheeler? (assuming their minimum weight is the same)

* = you mean drag here I presume.

yeahh i do mean drag thanks for the correction.

[Saribro]

As they say in thermo there is no free lunch

We can generalise this to the first law of engineering: Conservation of misery.
There's always a tradeoff.

[Scotracer]

As Tom said, you're increasing frontal area when going closed-wheel. However, your form drag is increased with open wheel.

[nas]

If we base the power numbers on the current Formula 3 engines that produce 210-215 hp out of 26 mm restrictor, then 20 mm should be good for 125 hp. I know this is simplistic, but we have to also take into account the fact that the F3 engines are restricted to 2.0 litres and here there is no such restriction. Again it may seem impossible to get any more power out of a bigger capacity engine (in the F3 case) considering the limiting effect of the restrictor, but we have to remember that a bigger engine will operate at a lower rev range (because of the limiting effect of the restrictor) and so it should be able to produce higher specific power from the same restrictor size due to the lower losses. So 125 hp should be definately attainable and more with further development, but any horsepower will not be coming cheaply, when you get into the range of diminishing returns.

[modbaraban]

Do the rules specify it was to be a pertol ICE?

[Ogami musashi]

Last year F1 cars were not so far in term of Lift/drag ratio from the LMP1's.

the F1 cars were around 3,5-4 and the LMP were just above 4.

The open wheels do create lift and drag but the great thing about open wheelers is that you have a lot of space to create (when rules do not prevent you from doing so) large efficient wings.

Current LMP's kind of struggle to get their front downforce with their diffusers and splitters hence the center of pressure is a bit aft.
They also struggle a bit to have good downforce on the rear wings and need wide ones.

[Conceptual]

Slim,

This type of vortex tube: http://en.wikipedia.org/wiki/Vortex_tube

And any exhaust turbocharger should suffice. After speaking directly to the manufacturer, their 3/4 inch model (19.5mm) will push 33cfm at max, but that can be increased by driving multiple tubes into an intake header, or manifold.

If someone has one of these engines, and live anywhere close to me, I have a manufacturer willing to send me 3 of them for a 90 day trial.

Slim, with that 9.9 number, does the temperature/density of the air matter? And can it be forcefed under pressure if the temp is way low.. (-30C).

Thanks!

Vortex tubes have lower efficiency than traditional air conditioning equipment. They are commonly used for inexpensive spot cooling, when compressed air is available. Commercial models are designed for industrial applications to produce a temperature drop of about 45 °C (80 °F).

so even well made units are not that good not to mention that they probably dont like the harmonics of piston engine. 80F isn't going to give much of power boost not to mention the weight and complexity this would add to a race car.

As they say in thermo there is no free lunch

Remember, that is a DROP of 45C from what you put into it! So 30C intake air would come out at -15C!

The quote that I got from the manufacturer said that with 30psi input, there is an optimim efficiency of 80%cold/20%hot, and the cold end would push 33CFM of -30C air while the hot side could be as high as 100C.

I am dead serious about this. If anyone on this forum has a small engine (kart maybe) that they would be willing to try this, I could be pursuaded to supply the vortex tube. Unfortunately, you will need to have some way to compress the air, and that may be the sticking point.

If anyone is willing to play with this, and report the results here, I will deffinately supply the tube.

PM me if you are interested!