Vodafone McLaren MP4-27 Mercedes

[Richard]

I've had to do a bit of a tidy up.

- Personal comments have been deleted. If you see yourself typing a comment about another poster's intelligence or personality then close down the computer and get some fresh air.

- The nature of civilian v military complexity has moved viewtopic.php?f=3&t=8031&view=unread#unread

- A few posts with random comments about "big ones" have been deleted

- Driver comments get moved here viewtopic.php?p=311790#p311790

Talk about the car please!

[shelly]

This article on coanda effects and passive fludic switches is very interesting. (also in the light of the supposed merc fw-duct and its hypotetical demo floaing this days on the internet).

pages 176-177 are the mostinteresting for jet deflection and show the importance of having a control flow near the jet exit. That could be what mclaren are trying to achieve by placing sidepod outlets near the exhaust.
The exhausts entrain the sidpod flow, and the sidepod flow acts as control flow for the exhausts' jet, possibly inducing swirl or guding its direction as shown in the article.

[Just_a_fan]

Which article Shelly?

[Crucial_Xtreme]

Have a look at the floor ahead of left rear tyre. Right click>view image

[shelly]

http://www.artechhouse.com/GetBlob.aspx ... 4_ch04.pdf

This article:

http://www.artechhouse.com/GetBlob.aspx ... 4_ch04.pdf

sorry, forgot to include

[Banki]

Hamilton is very quick in the first sector.
Which tyre did hamilton use on the best lap? As same as vettel's one?

[simieski]

with ref too pic from crucial...

just looks like accumulation marbles in front of the left rear again, would this building up in a race have a significant impact on airflow in this area?

seems mclaren have removed part of the restrictor type thing in the cooling outlet that they had in jerez. also... temp sticker below the rear light

[Coefficient]

I’m confused. Are we saying because we can’t have low pressure under the diffuser due to EBD ban that we are trying to create high pressure above to mimic or create a similar effect to EBD?

Also, with regard to exhaust plume expansion; does this expansion occur because the gases are reverting to a lower energy state just as all things in nature tend to do once artificial forces acting on them are either reduced or removed? In this case the engine being the artificial force creating the exhaust pressure which then has rapidly diminishing effect as the plume exits the outlet valve.

Are we hoping Mclaren are trying to expand the gases across the whole upper surface of the diffuser whilst at the same time maintaining enough pressure above said diffuser to exceed that below and effectively push it down?

[Jef Patat]

Measuring flow under the floor?

http://www.gpupdate.net/en/f1-photos/79 ... 9/#/192870

[Just_a_fan]

@Coefficient
My view is that McLaren are trying to mimic the edge sealing of the diffuser as with last year's EBD. The EBD is designed to help prevent the dirty air from the tyre ruining the flow under the diffuser. In effect it acts as a skirt to seal the diffuser and make it work harder.

The thing about the diffuser is that it's job is to get the flow below the floor to meet the flow above in the nicest way possible in order to reduce drag and improve efficiency. Ironically, this works best when the pressure difference across the diffuser is low. By having a region of high pressure above the diffuser you actually reduce its efficiency.

Look at the designs of the cars - they are all designed to get air to flow over the top of the diffuser - this flowing air will reduce the pressure above the diffuser and so make it more efficient. If you wanted to maximise the pressure difference across the diffuser you would have bodywork between the rear wheels in order to have a volume of still (and thus relatively higher pressure) air in this region. The teams don't do that - they want air to flow over the top of the diffuser. And flowing air has less pressure than still air.

[funkyfreddy]

Have a look at the floor ahead of left rear tyre. Right click>view image

I've not seen this mentioned before, appologies if it has been, but is there some kind of extra layer/lip around the diffuser on the mclaren? I can kinda see daylight just inside the edge of the diffuser all the way around.

Again sorry if its already been mentioned. Is this legal? isnt it bordering on a double decked diffuser?

[Coefficient]

Have a look at the floor ahead of left rear tyre. Right click>view image

[img]http://www.formula1.com/wi/sutton/2011/ ... 07.jpg[img]

I've not seen this mentioned before, appologies if it has been, but is there some kind of extra layer/lip around the diffuser on the mclaren? I can kinda see daylight just inside the edge of the diffuser all the way around.

Again sorry if its already been mentioned. Is this legal? isnt it bordering on a double decked diffuser?

yes, there is a Gurney on the upper trailing edge of the diffuser. Red Bull were doing that at the end of 2010 and kept the idea throughout 2011. Other teams also adopted the idea in 2011, Mclaren included.

[ajdavison2]

It's a full length gurney just like what RBR ran last year.

[Coefficient]

Have a look at the floor ahead of left rear tyre. Right click>view image

[img]http://www.formula1.com/wi/sutton/2011/ ... 07.jpg[img]

I've not seen this mentioned before, appologies if it has been, but is there some kind of extra layer/lip around the diffuser on the mclaren? I can kinda see daylight just inside the edge of the diffuser all the way around.

Again sorry if its already been mentioned. Is this legal? isnt it bordering on a double decked diffuser?

yes, there is a Gurney on the upper trailing edge of the diffuser. Red Bull were doing that at the end of 2010 and kept the idea throughout 2011. Other teams also adopted the idea in 2011, Mclaren included.

The Gurney doesn’t constitute a double diffuser. The double diffuser was literally two diffusers stacked one on top of the other with upper deck being fed by holes in the floor. This Gurney is just a strip of carbon stuck to the top of the diffuser.

[kilcoo316]

I think its just a fillet on the gurney flap....?