Reducing the drag of a two element wing through stall

[forty-two]

If you can have it manually controlled, why would you prefer an automatic, tuned system? Left hand activation (or left whatever) is just so simple, elegant, and, obviously, effective (See Ferraris, Saubers, Bulls, Renaults...).

I thought the same about KERS until I actually drove a hybrid car. A properly set up automatic system, assuming of course a neat way of doing this covering all the possible scenarios could be arrived upon would surely be better?

Let the driver worry about driving.

Anyway, I don't know the truth. I just thought it was worth mentioning that we don't know for sure that the McLaren system is indeed manual, or controlled by the driver's left 'insert appendage name here'.

[horse]

It could be penis controlled and they have HUDs in their visors which should show their girlfriends naked as they are exiting the corners.

EDIT: For sense.

[timbo]

It could be penis controlled and they have HUDs in their visors which should there girlfriends naked as they are exiting the corners.

I have my doubts about Sutil

[forty-two]

It could be penis controlled and they have HUDs in their visors which should there girlfriends naked as they are exiting the corners.

I have my doubts about Sutil

Do you know something I don't about Sutil, or is this an "in joke"?

[ringo]

The system is naturally automatic. I did a simmulation and put up a video a few months back.
It will work on it's own. The device is like a washing machine cycle, it's open loop.
For instance a washing machine will wash then rinse then spin on a pre programed cycle, however someone can turn the knob and skip a few steps or shut off the machine completely.
Mercedes Benz are using the open loop F duct which is fundamentally the simplest form.
The Mclaren F duct will switch on it's own at a certain speed or pressure signal, and it can be forced to switch by the driver's hand altering the signal.
It's like a boost controler on an automobile if one is familiar with that device.

[youtube]http://www.youtube.com/watch?v=L7eG2TosLY8[/youtube]
Here's the example again, at 30s into the video, the duct starts to transition.
The simulation is as if the F1 car is accelerating at 11m/s^2. This is happening on it's own because of how i set the pressure on the pipe that runs on the gearbox.
The pressure distribution is that of the bridge wing.

[ringo]

The question that has not been answered for the whole year is:
How does blowing air behind the wing stall it? No one truly knows this, we only accept it becuase that is how it is reported by journalists.
Newey and Horner say the wing is unloaded, but we truly don't know what phenomena is causing this.
I have tried summulating a couple times before and have no conclusive results.
I think I'll try again, it could be how i configured the duct.
I was ignorant to the geometry of it earlier in the year, now with so many teams running it, i have an idea how to make the duct effectively.

[forty-two]

Mercedes Benz are using the open loop F duct which is fundamentally the simplest form.

Aha! That's what I thought, but some posters on here have kept stating that the "control" feed goes via the endplates on the Merc. Not only do I see no evidence for this whatsoever, but I would imagine that routing the ductwork through all the fiddly corners would lead to massive losses in terms of pressure.

I suspect that the reason some people have this idea about the Merc is largely to do with an image which appeared some months ago which showed the Merc with a pitot tube taped to the wing endplates, presumably while they were evaluating it's performance, and it is this which led some to believe that Merc were routing their signal air via this path.

It then occurred to me however that the "signal" could be being fed to a fluidic switch housed within the "nostrils" on the Merc's wing, but this strikes me as way too complicated to be likely.

Thoughts?

[horse]

Mercedes have a large intake on the right of the chassis in front of the driver and a small one to the left. If they are not to act as a feed and control for an f-duct, then what are they for? I can dig out pictures from another thread if you want to see them?

[forty-two]

Mercedes have a large intake on the right of the chassis in front of the driver and a small one to the left. If they are not to act as a feed and control for an f-duct, then what are they for? I can dig out pictures from another thread if you want to see them?

I'd be very interested to see them, or indeed a link to the thread where they reside.

Thanks Horse

[horse]

I don't know why it's not considered a characteristic of the Mercedes, but the discussion was moved out of the car thread and now resides here (see the 4th-6th posts).

I agree that the route to the wing must be complicated, but the evidence suggests the original passive Mercedes f-duct was not good enough and, thus, they've done this to allow driver control.

[forty-two]

I don't know why it's not considered a characteristic of the Mercedes, but the discussion was moved out of the car thread and now resides here (see the 4th-6th posts).

I agree that the route to the wing must be complicated, but the evidence suggests the original passive Mercedes f-duct was not good enough and, thus, they've done this to allow driver control.

Well, I agree that this does suggest that something odd is going on there. With the Merc lacking a sharkfin through which to route to the RW, the only option would indeed be the endplates I suppose, but I struggle to see how they could make it work.

Thinking about this, it reminds me of practice at Spa, where MSC seemed to be putting his L/H glove over a hole at the START of a straight, removing it, and then briefly re-placing his hand at the end of a straight. This led me to believe that maybe Merc have a flip-flop type device which gets turned on by a single pulse and then off again by a second pulse.

But I still can't see how they're doing it!

Perhaps that's why they're not doing as well as they might so far this season?

[horse]

Well, I agree that this does suggest that something odd is going on there. With the Merc lacking a sharkfin through which to route to the RW, the only option would indeed be the endplates I suppose, but I struggle to see how they could make it work.

Well, this is just a punt, but I would suggest that the airflow is compressed into two small radius pipes that are fed up either side of the rear wing end plates and along the leading edge of the main element. Then those loops are used to decompress the air and feed it to either side of the main element.

[forty-two]

Well, this is just a punt, but I would suggest that the airflow is compressed into two small radius pipes that are fed up either side of the rear wing end plates and along the leading edge of the main element. Then those loops are used to decompress the air and feed it to either side of the main element.

I reckon that IF they're feeding the signal air up the endplates, the only logical way they could do it would be to have two fluidic switches housed within the "nostrils" on the wing. The signal air triggers the fluidic switch, allowing mainstream air flowing directly into the nostril to be fed to a blowing slot.

[horse]

I guess, forty-two, it could be a question of volumes. It could be that the exotic Merc wing with it's many ports is needed to get enough air through the wing when they use a large AoA, but they still get some control flow from the front of the car. With the low AoA wing used in Monza, perhaps the feed from the front provided a sufficient volume to stall the small wing. Like a micro f-duct. It would explain why MS was asked to test the apparently missing f-duct in free practise.

[marcush.]

wich is worth .2kph top speed.. maybe thats the case.