Vritual gurney flap

Post 13 Jun 2006, 19:25

one problem i see with this using exaust gas is that now your down force its heavily relient on throttle posistion so if a dirver backs out of it in a turn things go bad

some old DSR cars back in the day tried exuast blown tunnels only to reach the same result of cars swapping ends when you back off the throttle

R1ceboy32 · Post 13 Jun 2006, 19:31

cool idea but truthfully i see it as a structally nightmare. its going to be hard to keep that gap open when a load is started to be applied to the trailedge. How is an F1 wing made anyway, is it just a foam core with a carbon laminate or a totally different process?

Ciro Pabón · Post 13 Jun 2006, 19:33

Wait a minute: I know this has a slim chance of being a workable idea (even if the rules are totally "blown" by it). But what if it works? F1 cannot take any more downforce if it is going to continue to be an interesting sport.

I suggest we ask the administrators to erase this thread and ask you to burn all your notes...

Ciro Pabón · Post 13 Jun 2006, 19:40

R1ceboy32 wrote:... its going to be hard to keep that gap open when a load is started to be applied to the trailedge. How is an F1 wing made anyway, is it just a foam core with a carbon laminate or a totally different process?

Airplanes have a duct that goes through the first wing element and a slot on its trailing edge, you don't need to make a hollow wing. Airplane wings are made of aluminium: for example, the Antonov military cargo plane (I think, please correct me) has a similar system and it has no carbon fiber wings.

flynfrog wrote:one problem i see with this using exaust gas is that now your down force its heavily relient on throttle posistion so if a dirver backs out of it in a turn things go bad

Allright, add a compressed air tank between the exhaust turbocharged air and the wing. Probably a bad idea, as the flow is really high and the weight of the system would be high too.

But, anyway, blown flaps are useful only on landings, they take away too much power on the take off.

This is not a problem, but an advantage in a car: you get more downforce in the back while you are braking, simply by keeping the revs high. A simple valve can change things and stop the flow while you are accelerating. What you get here is a brilliant idea: you can change the properties of the wing, not by changing the wing itself but by improving the flow of air.

This is a system that you can even modulate to keep the car from having under/oversteering! And the rules are impotent about it.

I would call it the "ultimate unflexiwing"...

manchild · Post 13 Jun 2006, 19:48

Ciro, you suggested something like this?

That's different idea than mine but I get what you wanted to suggest (am I?)

Ciro Pabón · Post 13 Jun 2006, 19:51

manchild wrote:Ciro, you suggested something like this?

Yes. I wonder how hard the professionals in this forum are going to laugh about it...

miqi23 · Post 13 Jun 2006, 20:06

The upwash produced by the diffuser does the job any way! No need of any duct like that if you are concerned with flow separation on the flap?

manchild · Post 13 Jun 2006, 20:13

Duct is there solely for feeding even though its positive (secondary) effect would be increased stability since crosswind would partly enter duct and exit trough wing (incrased stability and downforce).

Speaking of "structural nightmare" someone suggested I don't see why would it be so. Wings are alrady hollow so all it would take would be to mould endplate to have NACA duct or not even that if struts would be used since they are already there and already hollow.

R1ceboy32 · Post 13 Jun 2006, 20:25

Well i know how traditional airplane wings are made, Al spars and skins. When you start to work with composites, you star to realize that a sheet doesnt have that much stiffness due to the lack of thickness. Hence when building a composite wing, a foam core is normally used to give it some thickness. I don't know the techincal terms for it ye but thats what we been doing in our SAE aero design compeition. Also a solid composite wing will not be light nor will one with mulitple layers. And F1 may have a different technique that allows them to have a hollow core which makes me look like an idoit. Attached is half of our wing which is a foam core and wrapped in fiberglass. [IMG:450:600]http://img201.imageshack.us/img201/7879 ... ium3va.jpg[/img][/img]

manchild · Post 13 Jun 2006, 20:30

Well, since F1 suspension arms (wishbones) are hollow and we all know what kind of forces they deal with I see no problem with wings being hollow too.

R1ceboy32 · Post 13 Jun 2006, 20:36

you do have a great point there. I wish i knew how to make my wings hollow. lol well our wing in the picture essentially only has one layer of fiberglass with carbon at the root and it weights only about 6 ounces and is about 4 feet long. we believe that using this foam core is the absoulte ligthest way of doing it. and we don't have serval million dollars avaiable for composites research.

Ciro Pabón · Post 13 Jun 2006, 20:41

miqi23 wrote:The upwash produced by the diffuser does the job any way! No need of any duct like that if you are concerned with flow separation on the flap?

Blown flaps work because they increase the speed of flow and diminish the stagnated layer over the wing, I think...

Am I wrong? Look, I work on systems for roads, no idea about car design, so please, be gentle...

Let me tell you a story: thirty years ago I was studying physics. A friend came with the idea of a microscope based on sound wawes. We all laughed and talked about wavelengths. Fifteen years later I was looking at a sonogram of my unborn daughter... Since then, I always say that when you encounter a new idea the burden of proof rests on the shoulders of those that can prove it does not work.

manchild · Post 13 Jun 2006, 20:48

R1ceboy32 wrote:you do have a great point there. I wish i knew how to make my wings hollow. lol well our wing in the picture essentially only has one layer of fiberglass with carbon at the root and it weights only about 6 ounces and is about 4 feet long. we believe that using this foam core is the absoulte ligthest way of doing it. and we don't have serval million dollars avaiable for composites research.

Why don't you make them in two pieces and than put them together using some fixture on both ends?

You could also make them in one piece using something inflatable to stick material you use for wing to the walls of mould you're using.

Ciro Pabón · Post 13 Jun 2006, 20:59

Sorry to post so much...

I have seen stadium roofs made with inflatable roof tiles (a recent idea, I think one of the World Cup stadiums has this kind of roof). Good for compression and of course, lightweight. I could not find one on the web, but surely you got it. So, you could try MC idea (the "Manchild inflatable wing") and use a inflatable core for your wing on sections where you need compression strength (near the pillars?). Probably you could want to make several cores with partitions to make it more torsion resistant. You could compress the air as much as you want to make it stiffer. Maybe you can shave some grams...

R1ceboy32 · Post 13 Jun 2006, 21:00

well as i said ealier one layer of carbon or fiberglass doesnt have enough stiffness for our needs once you start to add mutiple layers, everything starts to get heavy. as it is now, a layer of carbon is about equal to weight of the foam. And we also have a carbon tube spar running down in the foam that also adds a lot to our strenght which is being redesigned over the summer. Our wing has to be able to support almost 40 pounds at the moment. we do currently use a molding process for the fuse. its essentially made in two halves which are joined later as you said. the materail uses is honeycomb nomex sandwhich between two layers of fiber glass. its about 6 feet long and only weighs a pounds. its pretty incredible. we would use the nomex in our wings but the complex shape prohibts us from doing so. o yea, all the composite work do is cured under vaccum and in an oven.