Rear wing and following a car

[mike]

I recently had the time to watch a moto GP race and i have to say, "that is some real racing". Not that F1 is boring, but they sure can overtake alot!
I always thought that if you can follow a car in a corner than it should be a piece of cake to stab ur car down the inside a take the position. however, watching the monaco race the car following is constantly losing rear grip and therefore are unable to get in the same acceleration rate as the car in front.
From my layman's understanding of aerodynamics, the car in front has to be in a turbulent flow for the car behind to have good tow, but before it hits turbulent flow the car behind is unable to get as much downforce as they need to follow out of a corner, and since rear wings are in the same position, the car behind will alway lose out. its not about the mechanical/aero grip force for the cars its about maintaining the force in a straight line.
So why dont they just allow better diffusors (but non-DDD) and ban the rear wing after all?
yes diffusors lose downforce following as well, but clearly not as much as the rear wing. right??
And as for the front wing? just put is on top of the diffusor's exit and divert the exhaust/heat gas away from the top of the engine cover and thats it~?
Because watching the motoGP race it really gets me thinking, F1 would be more fun if its like this~!!!!

[timbo]

Because watching the motoGP race it really gets me thinking, F1 would be more fun if its like this~!!!!

F1 can never be nor never was like this. Only because of sheer width of the vehicles.

[speedsense]

You already answered your own question... because in motoGP they don't have wings, you have no problem with air being removed from your handling abitity. It is when you involve wings that you have a problem following behind the wake of any moving object. Heck, even airplanes can't fly within 20 miles of the wake of a 747, less they fall out of the sky, I know this because the Southwest airline flight I was on got put in the wake of one within 25 miles behind, and I was looking at the ground out the side window. The pilot told us they had put him too close to a 747, 25 miles away. Of course we're talking 600mph not 200mph........

[Roland Ehnström]

speedsense, Mike's question was actually "Why don't they ban the rear wing?". I don't know exactly why, perhaps they want to keep F1 cars the fastest cars on earth (on a normal race track), or perhaps they need the advertising space... Personally, I would love to see front- and rear wings banned. I don't want F1 to be a copy of MotoGP in terms of overtaking (and it never could be, given the width of the cars), but I would like to see a little more overtaking and close racing in F1.

[dave kumar]

I thought that the diffuser on a F1 car increased the effectiveness of the rear wing by creating a low pressure zone at the rear of the car. If you were to remove the rear wing wouldn't you lose a some or even all of the downforce that is added by the diffuser?

I'm sure this was answered in previous threads (by among others speedsense )

viewtopic.php?f=6&t=6545&p=110278&hilit ... ve#p110278

To prove out the downforce production theories, or lack of downforce production, take a winged car and add a diffuser to it. Note the added increase of downforce. Now remove the wings, and you will find that a high percentage of the "added" downforce has all but disappeared. The reason is that the device does not produce downforce, ie: negative lift- but simply helps remove the lift causing high pressure areas that develope undercar and grant the wings more downforce.

Here's an old thread from 2006 on the 2008 CDG Concept. Unfortunately none of the flow images are available but from the conversation it looks like the diffuser is actually responsible for generating a large amount of the upwash that was creating the problems for following cars.
viewtopic.php?f=6&t=2867&p=32202&hilit= ... ove#p32202

The car you are seeing in the images are actually a modified 2006 car to meet the 2008 regulations. As I said minimum changes and still meet the 2008 regulations! However, the new rules has opened a new door for further research in aerodynamics. The following image is an analysis on the actual car with the diffuser producing the up-wash which is causing a lot of problem nowadays. I did that to study the performance of newly designed rear wing with close proximity to the car.

Love to know if any contributors to that thread did any more CFD analysis on the interaction of rear wing and diffuser comparing 2008 and 2009 regs.

[kilcoo316]

yes diffusors lose downforce following as well, but clearly not as much as the rear wing. right??

I would disagree.


The rear wing is far above the following front wing, and does not induce the same vertical velocity fluctuations near the ground plane that the diffuser does.

[Scotracer]

In the OWG's research, they found that the diffuser was affected most of all by the wash from the car in front.

[mike]

In the OWG's research, they found that the diffuser was affected most of all by the wash from the car in front.

so your saying diffuser is to blame for the failure to follow a car in front??

[kilcoo316]

In the OWG's research, they found that the diffuser was affected most of all by the wash from the car in front.

Because the front wing endplates were f**ked?

[Ciro Pabón]

Welcome to the forum, binclintonusa.

I see no image in the link. Can you fix it? What is a "pret auto"?

[Ogami musashi]

No the OWG didn't find the diffuser was the most affected, they found out the diffuser turbulences were the ones that were the most harmfull because they are not eliminated as fast as the one from the wings.

However they found out that the lesser the GE downforce the better the diffuser kept his DF in wake.

Which was not the case with wings.

[riff_raff]

As others have somewhat noted, the problem with passing in F1 is not really the turbulence produced by the leading car. It's the effect that the turbulence has on the aero-balance of the trailing car.

An F1 car's handling is very sensitive to shifts in the aero C of P, which can occur when the front wing or underbody momentarily produces less downforce due to turbulent airflow. The instantaneous rearward shift of the aero balance produces loss of grip at the front and severe understeer. The driver of the trailing car cannot see the turbulence so he can't react to it.

Maybe the FIA should develop some sort of synthetic vision aid for the driver's visors that give them a real-time, visual display of wake turbulence flow. At least that way they might be able to avoid it. It might sound far fetched, but modern aircraft have warning systems that are somewhat similar.

MotoGP bikes aren't impacted by wake turbulence from a lead vehicle because they are designed strictly for low drag. Their handling is all coming from mechanical grip (plus how big the rider's cajones are ).

F1 cars will always have front and rear wings with huge, flat end plates. Those wing end plates are the most valuable part of the car, since that is the best place to put sponsor decals. The teams would never agree to get rid of a piece of composite that likely generates over $1000 per square inch in sponsor cash.

Regards,
Terry