McLaren MP4-29 Mercedes

[R_Redding]

According to Scarbs, Mercedes run a split-turbo, with the exhaust compressor at the back, but the intake compressor at the front of the engine. So the spiral would probably be the intake compressor.

It would look very similar to this Magneti Marelli one



Rob

[SidSidney]

I am not sure if this is interesting or of the right level of technical input, but I built a very Heath-Robinson Fimo model of one of those rear McLaren mushroom/bell/airbrakes, just to see how it worked in a flow of water:




OK, I know it is amateurish, unscientific, unrepresentative etc etc, but it was interesting to me to see just how sensitive this toy was to very minor angle of attack changes to the water flow, also the way the upper lip created a very high velocity whaletail and the lower lip was completely irrelevant as the leading edge dominated the flow direction.

Also interesting that the curved shape (as seen from above) of the model had a very strong impact on the whaletail shape of the upper flow, basically forcing it to spread out horizontally (compare the above and below flows; in other photos the effect was much more pronounced than in this one).

So I guess that the design of the upper gurney and the lower leading edge are two of the major design variables, even if the part is symmetrical through the section, and the angle of incidence is also critical to design. The longitudinal curvature also allows a relatively small part to create a much wider horizontal exit flow.

[Emerson.F]

Onboard JB.
http://www.dailymotion.com/video/k5ZCyWB9k2CMIm606Ef

[mclaren_mircea]

Any news about Mclaren's updates?

[Emerson.F]

Great shot

[FrukostScones]

oopsy

[turbof1]

Getting a closer look, it's interesting to see mclaren runs the main plane a few mm's higher above the ground then required. This is obvious by looking at the edge of the footplate.

[trinidefender]

Getting a closer look, it's interesting to see mclaren runs the main plane a few mm's higher above the ground then required. This is obvious by looking at the edge of the footplate.

Nice spot. I wonder if that is done to reduce sensitivity to ride height changes at the front, a problem that ground effect wings have.

[turbof1]

Should be something like that yes. It's a new philosohophy of front wing for them, so they are probably playing it safe for now until they have a better handle on the sensitivity. Though expect them doing so as soon as they are able to: it's an instant boost to L/D.

[trinidefender]

Should be something like that yes. It's a new philosohophy of front wing for them, so they are probably playing it safe for now until they have a better handle on the sensitivity. Though expect them doing so as soon as they are able to: it's an instant boost to L/D.

If it is due to sensitivity problems then yes I would expect them to lower the wing at some point assuming that they do get a handle on any sensitivity issues. Sauber have been running ground effect Venturi tunnels on their front wings for a few years now (not sure about this year).

To me it seems that McLaren are evolving their old wing step by step to get this current one. The inner wing planes seem similar to previous years own, wouldn't be surprised if the next change is of the very inside of the wing controlling the vortex that goes inside the front wheels.

[dren]

Should be something like that yes. It's a new philosohophy of front wing for them, so they are probably playing it safe for now until they have a better handle on the sensitivity. Though expect them doing so as soon as they are able to: it's an instant boost to L/D.

Also, haven't they historically run very stiff spring rates? Maybe they have gone with a softer suspension and are anticipating a bit more dive? I can't quite tell where the tea tray is relative to the ground, though.

I remember reading Button talk about last year's car porpoising down the track. So, you are likely right. The wing last year was probably gaining/dropping DF depending on how close to to the ground it was getting and causing the car to porpoise. That then has an effect on the diffuser performance with its distance to the ground. They may just want consistant stable DF from the front wing. That then takes away the need for my first suggestion.

[f1rules]

some high res pics
http://motorsport.nextgen-auto.com/gall ... ar/408.jpg
http://motorsport.nextgen-auto.com/gall ... ar/489.jpg
http://motorsport.nextgen-auto.com/gall ... ar/520.jpg
http://www.formule1.nl/media/uploads/me ... 236.31.jpg
http://www.formule1.nl/media/uploads/me ... 215.77.jpg

[SidSidney]

I was looking some more at that venturi device on the rear wing support/monkey seat of the 29. I was certain I had seen this configuration somewhere before:-



And here it is, as used to rapidly inflate airline emergency slides in seconds:-



You can see a video demo of what effect this device has, in terms of accelerating huge gobs of extra air mass through that hole, in this video from Richard Hammond's Engineering Connections (I know, highbrow):-

http://youtu.be/aU9ahW6H61s?t=32m12s

I think that device (an aspirator), driven by the exhaust, is accelerating a large amount of extra fresh air either out from under the engine cover - which may expain the extra large lateral ducts either side of the exhaust tunnel in the engine cover - or from the ambient air, directly over the top of the centre of the diffuser. Looking at how it is positioned, it could be either:-



If so, what impact does it have? It could be for cooling (sucking hot air out of the engine bay, or reducing the heat of the exhaust mix over the rear crash structure), or aerodynamic effect, working the rear end somehow.

Either way it's not coincidence - there has to be a reason for that layout. And Teams like Red Bull, Mercedes, Williams etc don't do it:

[Avocado]

http://www.f1fanatic.co.uk/wp-content/u ... 014-21.jpg
http://www.f1fanatic.co.uk/wp-content/u ... 2014-2.jpg
http://www.f1fanatic.co.uk/wp-content/u ... b-2014.jpg
http://www.f1fanatic.co.uk/wp-content/u ... 2014-3.jpg

http://www.formula1.com/wi/gi/4NW6/sutt ... 5ma133.jpg
http://www.formula1.com/wi/gi/_dTv/sutt ... 15ma91.jpg
http://www.formula1.com/wi/gi/T0x3/sutt ... 5ma397.jpg

[Pup]

I was looking some more at that venturi device on the rear wing support/monkey seat of the 29. I was certain I had seen this configuration somewhere before:-

Possibly in your almost identical post two pages back?

The inflatable ramps use an aspirator because if they tied the ramp directly around the hose, that airflow wouldn't be able to entrain additional air. So they attach it to a wider ring which allows for an airspace between. In McLaren's case, the exhaust will entrain additional air regardless of how the wing stay is shaped, because it isn't enclosed. I think the shape of the stay does more to speed up and condition the air coming through and over it than it does to bring more air in, though perhaps it does all of the above. (Most likely, imo, it acts to provide and speed up air flowing under the monkey seat.) As I said before, it probably does help internal cooling along with bringing air down over the suspension fence - though from the shape of the surrounding bodywork, it seems apparent that it's more about external airflow than internal.