McLaren MP4-29 Mercedes

[Ferraripilot]

Part 2:
https://www.youtube.com/watch?v=5U0fub3_DSU

I would be very interested in an expert opinion regarding drag penalty vs downforce, and about how many points something like this might be worth. The DDD was worth something like 15 points or thereabouts and I cannot (yet?) see this as being even half as efficient as such a drag free development as the DDD.

[turbof1]

I don't believe the DDD was really drag free. It would certainly have a much better L/D though.

For me the most important thing to know is how its coëfficient compares to the rear wing.

[Ferraripilot]

For me the most important thing to know is how its coëfficient compares to the rear wing.

Agree. I'm sure it was worked out well in their wind tunnel to make sense otherwise they wouldn't be using it, but just how good it is has yet to be seen. This car certainly has a sharp front end now that I've seen a good number of videos running. W05 looks understeery by comparison, but there are worse issues to have these days than too little front end downforce right.

[henra]

For me the most important thing to know is how its coëfficient compares to the rear wing.

Let's look at the fact that drag calculates as
Fd=Rho/2 *Cw *A*v^2

So let's have a look:
Rho: unchanged compared to Beam Wing
Cw: defnitely higher (Guestimate: >2 times higher).
A: >2 times as much.
v^2: Unchanged.
=> Drag probably >4 times higher than Beam Wing.
DF surely not higher than Beam wing.
=> L/D of the device itself probably around 4 times or more worse than Beam Wing.
The big unknown is the effect of this device on the diffuser compared to the Beam Wing's.
That said I would be surprised if it works much better on the diffuser than the Beam Wing.
The other Team's Designers would probably also be keen on having an idea how efficient it is.

I'm still not sure if we will see it on all tracks. Gutt Feeling says: Possibly no. Especially Monza and Spa. Then again the questions is if they accept a little disadvantage on those tracks rather than change it to 'normal' ones, endangering their case that it is simply their normal Suspension and not some aerodevice in disguise.

[FrukostScones]

"Downforce at any price."

http://translate.google.de/translate?hl ... 52436.html

Automotorundsport.de on the McLAren Mp4-29 with nice picture slideshow.

[Pup]

Gotta love google translate - fireplaces on the side pods. Sounds cozy.

[Rikhart]

I liked this article, and it has a couple of photos I have not seen brought up before on the thread:





http://grandprix247.com/2014/02/07/tech ... explained/

[Chuckjr]

For me the most important thing to know is how its coëfficient compares to the rear wing.

Let's look at the fact that drag calculates as
Fd=Rho/2 *Cw *A*v^2

So let's have a look:
Rho: unchanged compared to Beam Wing
Cw: defnitely higher (Guestimate: >2 times higher).
A: >2 times as much.
v^2: Unchanged.
=> Drag probably >4 times higher than Beam Wing.
DF surely not higher than Beam wing.
=> L/D of the device itself probably around 4 times or more worse than Beam Wing.
The big unknown is the effect of this device on the diffuser compared to the Beam Wing's.
That said I would be surprised if it works much better on the diffuser than the Beam Wing.
The other Team's Designers would probably also be keen on having an idea how efficient it is.

I'm still not sure if we will see it on all tracks. Gutt Feeling says: Possibly no. Especially Monza and Spa. Then again the questions is if they accept a little disadvantage on those tracks rather than change it to 'normal' ones, endangering their case that it is simply their normal Suspension and not some aerodevice in disguise.

Ya think? I'm betting it will give so much more efficiency to the diffusor that swapping it out will be catastrophic to the balance of the car. My gut says they have designed the whole car with this as a central contributing aero element to the cars equilibrium--which is why I think they introduced it at the first track rather than waiting. My gut says it will stay at all tracks. Honestly, I don't think we can really know at this point how these things affect the cars aero efficiency, so it can't be flat assumed it's severely detrimental.

[Lycoming]

I would be very interested in an expert opinion regarding drag penalty vs downforce...

Define "expert".

My gut says they have designed the whole car with this as a central contributing aero element to the cars equilibrium

This is almost certain. They may well have designed it such that the diffuser will not work nearly as well without it.

--which is why I think they introduced it at the first track rather than waiting.

Or, possibly, they don't have a set of normal wishbones to test it with in any case.

[Chuckjr]

My gut says they have designed the whole car with this as a central contributing aero element to the cars equilibrium

This is almost certain. They may well have designed it such that the diffuser will not work nearly as well without it.

--which is why I think they introduced it at the first track rather than waiting.

Or, possibly, they don't have a set of normal wishbones to test it with in any case.

If such is the case, and they are outlawed….holy god.

I wonder if it will become 2009 all over again. Surely they wouldn't have that drastic an effect.

[turbof1]

I believe they can work without it. I'm sure mclaren does have a backup plan if this concept gets outlawed.

Also, @Henra: nice calculations, though I am actually more interested in how it compares to the rear wing (as mentioned) instead of the beam wing. If it happens to be adding better L/D then what the rear wing does, then you can more easily take some rear wing away.

[timbo]

If it happens to be adding better L/D then what the rear wing does, then you can more easily take some rear wing away.

I really don't think this is possible. Because the regulation Ddemand the profile to be symmetric it deflects too much air where you wouldn't want it.

[Holm86]

I really cant imagine it having a better L/D than the rear wing either.

[turbof1]

I really cant imagine it having a better L/D than the rear wing either.

It really depends on what it does with the diffuser. The L/D of the elements themselves of course is poor, but it certainly boosts downforce from the diffuser. Enough to make the whole addition more efficient then the rear wing? I don't know; mclaren seems to have faith in it.

[PhillipM]

I really cant imagine it having a better L/D than the rear wing either.

Depends how hard it drives the diffuser and sidepod flow, in isolation, they would be terrible, but if it gives the same as the rear wing when combined with the diffuser benefits, I could see them just flattening the rear wing out, as I've said before though, I wouldn't be too surprised if one pair of elements disappeared at the fastest tracks.