Vodafone McLaren MP4-27 Mercedes

[Shakeman]

Rumour has it the McLaren bulges aim hot air at the diffuser.

The bulge circulates air from the side pod round the exhaust then dumps it out an exit in the bottom of the bulge aimed at the outside edge of the diffuser.

Was this your source?

http://forums.autosport.com/index.php?s ... try5508062

It makes no sense.

Why does it make no sense? Air in that area can only be a good thing surely?

Not directly but what I saw could've come from that post.

The bulges must be performing some function as I cannot see McLaren bolting such an ungainly device to the side of they car for no benefit. So far I've not seen any technical chat about their function and for me they're the most interesting features of any car released so far.

[raymondu999]

It do looks wider but its much more shorter compare to its predecessor

On this topic actually, can anyone make up a to-scale comparison of the MP4-25 and -27? This was the best I could find:
http://mclarenf-1.com/index.php?page=srch&ch1=5&ch2=22

But hideously off scale and from different angles (look at the rear wing on both)

[Spencifer_Murphy]

Rumour has it the McLaren bulges aim hot air at the diffuser.

The bulge circulates air from the side pod round the exhaust then dumps it out an exit in the bottom of the bulge aimed at the outside edge of the diffuser.

Was this your source?

http://forums.autosport.com/index.php?s ... try5508062

It makes no sense.

Why does it make no sense? Air in that area can only be a good thing surely?

Not directly but what I saw could've come from that post.

The bulges must be performing some function as I cannot see McLaren bolting such an ungainly device to the side of they car for no benefit. So far I've not seen any technical chat about their function and for me they're the most interesting features of any car released so far.

The heat exchanger idea makes no sense because heating the flow of air from inside the sidepod does not add velocity to it (the flow). In addition it would make the air less dense, thus reducing the mass-flow rate of air being used to "blow" the diffuser. Lastly I can't seem to find any exits around the bulge for this air to be expelled from the sidepods and to the diffuser; unless we consider the outlet at the centre near the diffuser but if that was the case we come back to point 1. why bother to heat the air?

That all being said though, I am also interested by these bulges, but I believe their "secret" is more to do with how they develop, are we going to see other iterations of the design etc?

[Caerdroia]

is this the second air inlet for cooling?

The MP4-26 had a cooling inlet in the same place last year which was used for the KERS cooling, so I'd assume the inlet cools something on the 27 at least.

[Crucial_Xtreme]

The exhaust of the MP4-27 launch car was made of plastic. Very good holding back McLaren. )

[Locoblade]

But these side pods are directly comparable to the MP4-25; especially as the intake is the same shape pretty much. I haven't compared them side by side, but this definitely looks bigger

KERS wasnt used on the MP4-25 in which means less cooling required, hence the smaller size?

[shelly]

The exhaust of the MP4-27 launch car was made of plastic. Very good holding back McLaren. )

How did you learn that?

[Caerdroia]

The exhaust of the MP4-27 launch car was made of plastic. Very good holding back McLaren. )

How did you learn that?

http://www.f1zone.net/news/boss-admits- ... sts/11995/

[Spencifer_Murphy]

Interesting, seems to confirm the suspicions of myself and a few other users in that we will probably see some other solutions to the exhaust area on the MP4-27.

I'm looking forward to the tests now!

[Lycoming]

as it says in the article, its a model, not a full working car. Who cars if its made of plastic. The real cars have probably long since been sent on their way to spain.

On the other hand it looks kind of crude to me. I would not be surprised if its gone by march, replaced with something more refined. It seems almost like a placeholder to me, and whitmarsh's comments in that article certainly confirm thats not outside the realm of possibility.

[beelsebob]

The heat exchanger idea makes no sense because heating the flow of air from inside the sidepod does not add velocity to it (the flow). In addition it would make the air less dense, thus reducing the mass-flow rate of air being used to "blow" the diffuser. Lastly I can't seem to find any exits around the bulge for this air to be expelled from the sidepods and to the diffuser; unless we consider the outlet at the centre near the diffuser but if that was the case we come back to point 1. why bother to heat the air?

That all being said though, I am also interested by these bulges, but I believe their "secret" is more to do with how they develop, are we going to see other iterations of the design etc?

Huh? No – heating air doesn't magically make some of it's mass disappear.

Yes, it makes it less dense, but the mass remains constant – the volume increases, which causes the velocity to increase, especially when pushed through a tiny exhaust hole. This is the same principal a jet engine works on.

[she_spools_180]

The heat exchanger idea makes no sense because heating the flow of air from inside the sidepod does not add velocity to it (the flow). In addition it would make the air less dense, thus reducing the mass-flow rate of air being used to "blow" the diffuser. Lastly I can't seem to find any exits around the bulge for this air to be expelled from the sidepods and to the diffuser; unless we consider the outlet at the centre near the diffuser but if that was the case we come back to point 1. why bother to heat the air?

That all being said though, I am also interested by these bulges, but I believe their "secret" is more to do with how they develop, are we going to see other iterations of the design etc?

Huh? No – heating air doesn't magically make some of it's mass disappear.

Yes, it makes it less dense, but the mass remains constant – the volume increases, which causes the velocity to increase, especially when pushed through a tiny exhaust hole. This is the same principal a jet engine works on.

Being only a recent graduate of engineering, I feel almost not worthy of posting on this forum with my limited understanding, However:

I missed the part about how you suggest to heat the air. Whether it is using a heat exchanger heated by coolant or whatever, or an exhaust pipe for example - specifically NOT using exhaust gasses, as this has been established that it is not allowed by the rules - just the heat from the pipe/hot surface itself.

Taking the heat exchanger (radiator) for example, I would think that the flow of air through the fins of the radiator would be rather restricted and therefore slowed down, negating any benefit of heating the air and increasing its velocity?

Although I do not know much about the passing air flow properties of an F1 radiator...

[murtoidf1]

So the MP4-27 becomes the only front running car not to feature a stepped nose on launch.

It's slightly unsettling, but I guess if any team could make it work it would be McLaren.

Out of interest, is there any way the team could change their nose layout before the season began (not taking into consideration the compatibility of a stepped nose on the existing rear end), or is the design locked in place due to crash tests etc

[Raptor22]

no, they would need a new tub as well.

[raymondu999]

which in turn is homologated to be kept for a year, no?