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Old 01-24-2013, 11:34 PM   #21
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Sorry, but F1 teams don't scrap ideas because it's too complex to make the part. If anything, expect new ideas to be more complex and expensive to make, not less. And rules won't stop that - they'll just come up with a new crazy way to go faster while working around the rules.

On a slightly related note, the RedBull cars have been running rubber noses that flex as a unit so that at speed they get closer to the ground. Cool.
They're not rubber noses, they are still some sort of carbon kevlar composite, the noses are just designed to flex at an amount of force higher than the testing force from the FIA. And this effect seems to have been reduced in the past season with the ugly noses. And speaking of the ugly noses, only redbull has an air inlet in anywhere close to the "correct" position shown in this video. An F1 team will scrap an idea. F1 teams go through an entire truck load of wings testing them, if they wing is so complex that they can only afford to make a few within the time constraints they have for testing and the budget caps set by the FIA they will likely scrap an idea, unless it shows itself to be worth it.

So you two are either trolling, and sucking at it, or need to go do some research. Either way, this topic offshoot needs to stop.
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Old 01-25-2013, 12:51 AM   #22
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... and the budget caps ...
When did these come into effect?
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Old 01-25-2013, 01:01 AM   #23
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Think about it... G-forces (lateral and/or longitudinal acceleration) will change the trajectory of anything with mass that is not directly tied to the frame of reference. The trajectory of the air (which has mass) is changed relative to the direction of travel of the car. It's not bullshit quasi physics, just physics.

For those not used to free body diagrams and dynamics, let me illustrate. Attach a water hose in the center of your dash firing straight back along the centerline of the car. Take a corner and the stream of water's trajectory shifts in the opposite direction away from the centerline of the car. The harder you turn, the harder it shifts. Lateral trajectory shift due to lateral acceleration. The same thing would happen if you directed the stream sideways, and slammed on the brakes. It's not voodoo, it's a cool idea.

I'm not talking about double DRS, this is something different.
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Old 01-25-2013, 01:25 AM   #24
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It would be a cool idea, if air had enough mass for that to work. Air flowing through a box is going to take the path of least resistance, also know as the path with the greatest pressure differential, and no matter how violently you accelerate it side to side you will not change that. The air will flow through all the holes and the volume flow distribution will be directly proportional to the pressure differentials. Now with a fluid with a significantly higher density, like water, the acceleration would actually change the the pressure profile side to side in that box which would change the rate. That pretty cfd in that video, go try to repeat that with the assumptions you're making, the cfd is 100% faked.
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Old 01-25-2013, 02:29 AM   #25
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If you make air travel fast enough (and don't slow it down too much when "touching" it) it will behave less like air in confined spaces (i.e. compressed air to tools etc). But to do that in "ducts" and trough "porous material" sounds fishy.

Like trying to make power in a running stream, you can make some with propellers/wheels etc, but to create static pressure you have to build a dam.

But if the speed where it might be feasible is 100mph or supersonic, I don't know (how many Gs are needed to divert airflow at all, it's not like you notice a change in HVAC air when you take a corner in your DD).
I assume it's not AutoX-speed at least, where barn-door sized aero is needed to get any effect (and not by flow over wing, but rather creating pressure by diverting air).

The Trunk-high-pressure-usage: If the high pressure zone is short and wide, just make the opening/ducts the same shape, as with any air intake in front of the windshield.
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Old 01-25-2013, 01:19 PM   #26
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I like how someone is calling bullshit on all the top F1 aero designers... just saying, there's a reason they have their jobs, and a reason the cars get faster every year. They know their field better than we do, and it would be foolish and pompous to claim otherwise. Not saying it's bad to question things - but accept that there may be things you don't understand well enough.
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Old 01-25-2013, 02:00 PM   #27
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Agreed with Mr Pass. Assuming the vid is not fake, if teams use anything like that this year, then it'll be because it works. We'll find out in a few months, I guess.
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Old 01-25-2013, 02:03 PM   #28
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The concept of path of least resistance is an oversimplification that is frequently overused when explaining the flow of water, air, electricity, forces, loads, sewage, whatever. It is true in its basic premise. But, anyone who understands engineering or physics knows in a system that it is not absolute, is much greyer, and depends on a lot of factors.

I agree, I would really do my homework before I called bullshit on something any of the renowned F1 aero designers are trying/doing. Aerodynamics (at least until recently with the new engine formula) is where most of the advances are in F1 and where most of the R&D money is spent. Some of the best and brightest are working in that area. Sure they are fallible, but it's more likely they are right than any one of us relative amateurs.
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Old 01-25-2013, 02:28 PM   #29
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I for one, wasn't calling bullshit on any aero or other devices actually used in formula 1.
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Old 01-27-2013, 06:16 AM   #30
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Ok when I get back home I am going to finish my under car aero and one thing I wanted to discuss was front diffusers.

I get something like this where it is solving two purposes. Helping move air into the brake region and help accel the air under the splitter.



But I don't get this. Why do you want the air to accelerate then slow down with turbulence, then find its way out to go to the underbody.

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Old 01-27-2013, 06:27 AM   #31
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I wanted to do this for a long time, to build a fan car. It would be interesting if motorsport could use this again.

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Old 01-27-2013, 11:56 AM   #32
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I wanted to do this for a long time, to build a fan car. It would be interesting if motorsport could use this again.
Cheaparral Champion Corvette

around 3:40 they show the car running and you can see the plume of debris it throws up. I wouldn't want to run behind that car on a track.



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Old 01-27-2013, 12:04 PM   #33
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IIRC the main issues they had with the mechanical bits to make the F1 fan car work:
1) They had to seal the car down, and seal meant to run skirts that wore themselves on the track.
2) The one race they were able to run at , there was a seam where old/new pavement met that was ripping the skirts off till they figured a way to make it ramp up onto the pavement better. (I believe the driver said that the jump when it hit that seam they were losing all suction, but it was on a straight, so they were not worried about it.
3) The fan at the time, it got thru the rules as it “sucked air thru the radiator” Later testing iirc it pulled around 35-38% of the air thru the radiator.
4) The materials for the fan, when the car was made I am sure they were using the most high-tech of stuff possible, but something with the gyroscopic forces and its RPM, at the end of the one race, its bearings were shot, and they were surprised it did not explode on the track. Their testing their fan kept blowing up, so they one race the fan lasted just long enough
If I can remember when I get home I have the story about this car in a book, there was something about their straightaway speed was slower than all the other cars (10-20 mph), but did not have to slow down at all for the corners, (like a 30-50mph difference)

That vid, I would more concerned with having that fan right beside you spinning at high RPM. I have seen some nasty pictures of exploding flywheels on drag cars before, that shroud does not look safe. I would have mounted it behind the driver and made some kind of barrier made of steel to guard in case it exploded and deflect it (and the air) away from the driver.

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Old 01-27-2013, 01:10 PM   #34
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But I don't get this. Why do you want the air to accelerate then slow down with turbulence, then find its way out to go to the underbody.

My guess is that it's out of necessity - they can't get enough of the air out of the hood (or don't want to - street car that they don't want a big extractor hood on or something), and so the air leaving the radiator must exit out the bottom of the car. This is how all of our cars expel that air as well, after all, except that we don't have any fancy ducting routing it out nicely, it's just a turbulent mess flowing out from the oil pan/bell housing area. I would think that guiding it, like in that pic, at least improves the way the air joins the air already passing under the car better than no guidance. Of course, if you can send all the air exiting the radiator up and out the hood, that's better, but not every setup has "maximum performance" as the one and only priority.

That's all just my own conjecture on that subject though.

Interestingly, the F50 has something kinda similar - the center section of the bumper is basically a splitter/horizontal fin, and the air going over that is then channeled down and under the car. But, the airflow for the coolers are on either side of that center tunnel, and the air for those is all exited out the hood:

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Old 01-27-2013, 01:55 PM   #35
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My guess is that it's out of necessity - they can't get enough of the air out of the hood (or don't want to - street car that they don't want a big extractor hood on or something), and so the air leaving the radiator must exit out the bottom of the car. This is how all of our cars expel that air as well, after all, except that we don't have any fancy ducting routing it out nicely, it's just a turbulent mess flowing out from the oil pan/bell housing area. I would think that guiding it, like in that pic, at least improves the way the air joins the air already passing under the car better than no guidance. Of course, if you can send all the air exiting the radiator up and out the hood, that's better, but not every setup has "maximum performance" as the one and only priority.

That's all just my own conjecture on that subject though.

Interestingly, the F50 has something kinda similar - the center section of the bumper is basically a splitter/horizontal fin, and the air going over that is then channeled down and under the car. But, the airflow for the coolers are on either side of that center tunnel, and the air for those is all exited out the hood:

And that brings me to something else I will be doing for another car of mine. Im going to wait until after my LS swap this summer or I am going to get ancy and build one now. I was thinking about the LS intake and how it is right in the way. So I am going to separate the ducts with the exits in the hood right about where the DTM cars do.

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Old 01-27-2013, 03:24 PM   #36
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Yeah with that last picture you can really see the wicker just before the opening to really get that low pressure zone there.

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Old 01-28-2013, 12:59 AM   #37
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I wanted a place to put mixed info about all Race Car Aero, not just Miata's but Ideas. Yes I know there is Treads currently about "Miata DIY Aero", "New Wing toTest" and some Miata under body Aero from ThePass and me. I was going to put some ideas and questions up on my "Miata Underbody Aero" but that would be off topic and can not share what your ideas are. And maybe "plucas" can share what he is thinking of since he has the knowledge and programming with data to give us.

The one of the things that I was looking at that brought up the idea of this thread was this found on the Nissan GTR GT1 race car. What is the function of this vent? or what is it?

Since I didn't see anyone answer though I would like to speculate on the matter it looks to be a cooler of some sort. With out doing any research on the car Idk if it's a diff cooler, inter cooler or what but you can see a line going in to the side.

If you do a quick google on chris griswold mustang you'll see that guy does that with a rear mount IC
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Old 01-28-2013, 01:35 AM   #38
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Since I didn't see anyone answer though I would like to speculate on the matter it looks to be a cooler of some sort. With out doing any research on the car Idk if it's a diff cooler, inter cooler or what but you can see a line going in to the side.

If you do a quick google on chris griswold mustang you'll see that guy does that with a rear mount IC
^ Covered that in post #2 of the thread
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Old 01-28-2013, 02:02 AM   #39
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^ Covered that in post #2 of the thread
yup, guess you got it. I must have glanced over it and not seen it. and damn the second post too.

In other news while reading the thread the 2012 Audi ultra A5 DTM Hood Vent pics make me moist.

I finally got my fluid dynamics book in the mail to start reading up on aero stuff and can't wait to dabble on my own, those hood vents look so sexy though
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Old 01-28-2013, 03:15 AM   #40
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Naturally the Audi DTM has a much more elegant wickerbill/gurney flap, but here's the crude one I just added to my hood vent:

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Last edited by ThePass; 01-28-2013 at 03:52 AM.
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