The Best Performing Rear Wing for the FRS/BRZ/FT86

[Tcoat]

So I have to ask.
What are your testing methods?
What are you measuring?
How are your measurements taken?
What supporting evidence can you provide to prove your claims that this wing "will improve perform better than competitors"?

[Hot Lava]

Originally Posted by MRE

Yes I have. Because of the wing placement, there wouldn't be enhanced lift anywhere, and yields only net downforce across length of the car.

The down force + drag multiplied by their respective distances perpendicular to the rear wheel act as a torque applied to the rear wheel lifting the front up. Is that factored into your analysis? The car already has an issue with aerodynamic lift on the front end at speed. Just a concern.

[MRE]

Originally Posted by Tcoat

So I have to ask.
What are your testing methods?
What are you measuring?
How are your measurements taken?
What supporting evidence can you provide to prove your claims that this wing "will improve perform better than competitors"?

The only testing method done so far are CFD simulations of the wing on its own, and the wing on another vehicle. CFD of the wing with the car will take place very soon I hope. There will be live testing as well.

In the CFD, the quantity of highest interest to measure are lift, drag, and force displacement, along with some other quantities. In live-testing, fuel economy, lap-time improvement, G-circle, and linear braking will be measured.

CFD spits out the results after letting it run through its equations an arbitrary amount of iterations. The live testing would utilize equipments such as linear potentiometers, stop watches, gps, distance measuring devices, and accelerometers, to acquire the measurements I've stated.

A good solid evidence for this is the results I've gotten so far with my wing in CFD. My wing with the experimental endplate, at 120kph, makes 201.2lb lift and 49.6lb drag. In comparison, the APR GTC-200 at 130kph makes 110lb lift and 16.5lb drag. Despite the increase in drag, The huge leap in downforce will still yield results around a track much better than the APR.

[MRE]

Originally Posted by Hot Lava

The down force + drag multiplied by their respective distances perpendicular to the rear wheel act as a torque applied to the rear wheel lifting the front up. Is that factored into your analysis? The car already has an issue with aerodynamic lift on the front end at speed. Just a concern.

The assumption is true if you are analysing the car without an underbody for air to travel through. Without an underbody, you are right, the position would create moment force, causing lift to the front.

The placement of my wing allows not just production of downforce from the wing alone, but synergy of underbody flow. There exists an increased flow velocity under the car, which is enough to counter the lift being produced from the moment force. I confidently state this being true, because in the experimentation done on another vehicle, the placement and position of the wing reduced lift(created downforce) at the front of the vehicle.

[extrashaky]

Originally Posted by Hot Lava

How much will it unload the front end? Have you considered what effect your wing will have on the front?

Shhhh! Don't give him any ideas.

[TJ3000]

I think what OP is trying to do is cater to the HPDE Guys he's going for function over form.



Take for example this pic, yes that hood spoiler looks rediculous but he's going for distance and he's going for speed.

[Guillaume]

Originally Posted by MRE

The only testing method done so far are CFD simulations of the wing on its own.

Doing it on your own with a computer never qualified as real life experience.

[joe strummer]

I applaud your efforts, for what that's worth. Good on ya, mate.

One bit of advice, you did solicit any feedback- "Please express your thoughts and opinions. Ask questions if you have any. Any feedback is appreciated."

In the future, you might want to restrict that to- Any intelligent and/or constructive feedback is appreciated.

I have no idea why there is such negativity on this thread.

[ZDan]

Originally Posted by MRE

The assumption is true if you are analysing the car without an underbody for air to travel through. Without an underbody, you are right, the position would create moment force, causing lift to the front.

The placement of my wing allows not just production of downforce from the wing alone, but synergy of underbody flow. There exists an increased flow velocity under the car, which is enough to counter the lift being produced from the moment force. I confidently state this being true, because in the experimentation done on another vehicle, the placement and position of the wing reduced lift(created downforce) at the front of the vehicle.

I don't think you can just *assume* that an underbody will counter all of the lift you're going to get at the front of the car from the downforce and drag of this wing. I predict that you're gonna need a BIG splitter up front to balance the car, if not a big front wing like in the tC pic!

Approach seems to assume that "more downforce is always better". If you have a ton of power, yes. But on a 200hp car, you're likely to lose more on the straights than you gain in the corners with a wing this big.

Giant wings like this are for slower courses like autoX, or for cars with big horsepower like this 875hp Pikes Peak Peugeot:

Actually, looks like this car has a *smaller* wing than yours. Also, note the front splitter required on this car to balance the rear wing.

[Simplicity]

I can see it being practical on the tracks, but in the streets, you'll be looking like a fool..

Via Note 4 using Tapatalk.

[Tgionet]

I'm looking at your endplates and thinking you could get a better l/d ratio if they were slotted. I think you'd do better with a larger main element and a smaller, second, and third elements at a higher angle of attack. You'd be bleeding off a lot of the pressure and minimizing the vortices coming off the wing.
Have you decided how you're going to be mounting, and supporting, it?

Also think you'd be getting much better feedback in the track section of the forum.

[Caspeed]

Originally Posted by MRE

Yes I have. Because of the wing placement, there wouldn't be enhanced lift anywhere, and yields only net downforce across length of the car.

It sounds like you need a lesson in vehicle dynamics if you think your statement is correct.

[paulca]

Originally Posted by MRE

That statement is not true. Aerodynamics affects all speeds. Going beyond an arbitrary speed does not create a binary condition for when a wing functions or not. The efficiency of my wing allows much more noticeable effect in increased turning speeds and reduced braking distance, compared to the competing wings in the market. The biggest factor dictating the downforce goals I've set is the mass of the car. The wing, being shaped and sized the way it is, a by-product of the performance goals I've set.

All aerodynamic forces increase with the square of speed. So the wing will be generating four times the down force at 80, versus 40.

This fact makes wings on street cars pointless. At legal street speeds they will only really start to be of any use on freeways at high speed.

The aerodynamic forces produced by almost any wing will be "negligible" below 30mph, at 60mph they will be 4 times negligible and only then will there be any tangible effect.

Most airliners don't even bother checking the controls for feedback until 80knots on the runway. Although some planes will fly at 40mph they have HUGE, thick, high area wings to do so and they weigh very little, like a quarter of what our cars weigh. My paraglider will fly at 20mph, but it lifts only 120Kg and needs a 9 x 3 meter (27m^2 area) wing to do so! The wing is also over a foot deep!

I would conclude that a wing for downforce is all but pointless on a street going car. The negative effect of the drag produced would also put one off regarding fuel effec. This is why Porsche etc. only have their wings pop up over 60mph when you brake.

I am not including spoilers in this of course, they serve a different purpose.

[Defuser]

I'm no engineer, but I fail to see how the downforce can be evenly distributed over the entire car when the wing is attached behind the rear wheels.

As has already been mentioned, there also must be some lift created at the front. Have someone sit on the back bumper of any car (with a suspension); it doesn't take a rocket scientist to predict the general effect of the weight on a vehicle.