McLaren MP4-26 Mercedes

[astracrazy]

I have been thinking about this regarding sidepods,
...

the vertical part of the sidepod may be needed to meet cooling requirements and also pass the crash test?

[Owen.C93]

Great explanation! Thanks a lot

Remember that there is a very low pressure zone behind the rear tyres so if you can attach the air flow to there it will really help the diffuser, I suspect that's what the RB style exhaust does as well.

[SiLo]

Anyone got any pics of the exhaust setup they ran in the race?

[LotusF1]

Which 4 holes? Do you mean the extension of the rear wing to the level of the diffuser?[/quote]

Okay, i miswrote that completely

I mean the four holes beneath the AkzoNobel sticker It's to channel the air out,... but i don't see how it gives the car an advantage,... I also didn't see it on other cars.[/quote]
It's a device seen on cars in previous seasons. If you look closely, you'll see that the vanes are curved with each being slightly different to the others. The obvious aim is to turn the air flow outwards - presumably to try to link the diffuser to the space behind the rear tyres.

The aim is to improve efficiency or directly increase downforce. We can't know the exact details of how it works because we don't know the exact flow in this volume.[/quote]

imo wrong...if you look closely they are 4 airfoils. imo they aid extration as they are close to a fence facing their low pressure part towards the diffuser helping with extration - therefore increasing velocity coming out.

you definitly dont want flow from the rear wheels. its low energy and thats why they blow the exhaust in between the rear wheels and diff.

[Just_a_fan]

Indeed but the flow from an aerofoil is turned and in this case it will turn out toward the space behind the rear wheels. That can only happen if that volume can accept the flow. Thus the rear wheel wake helps the endplate extension do its job of assisting the diffuser.

If we look at the endplate aerofoil nearest the diffuser, we can see the aerofoil section is oriented on the line of the diffuser strake. Those further from the diffuser are less turned. This suggests they're trying to turn the flow outwards.

[alelanza]

Hello!

http://motorsport.nextgen-auto.com/gall ... medium.jpg

Can anybody explain to me what the the four holes are for at each side of the endplate?

Thanks.

http://scarbsf1.wordpress.com/2011/03/18/1322/

[LotusF1]

Hello!

http://motorsport.nextgen-auto.com/gall ... medium.jpg

Can anybody explain to me what the the four holes are for at each side of the endplate?

Thanks.

http://scarbsf1.wordpress.com/2011/03/18/1322/

scarbs didnt get this completely right imo...you dont extend the fences or the diffuser. imo you just improve extration...making it quicker...

[bot6]

Yes, you improve the extraction... By extending the diffuser fences. Which isolates the diffuser from the wake of the tires a bit more, and limits turbulence of the air exiting the diffuser as it mixes with the air coming in from the sides of the car.

So you're right but so is Scarbs. It's just saying the same thing in a different way.

[LotusF1]

Yes, you improve the extraction... By extending the diffuser fences. Which isolates the diffuser from the wake of the tires a bit more, and limits turbulence of the air exiting the diffuser as it mixes with the air coming in from the sides of the car.

So you're right but so is Scarbs. It's just saying the same thing in a different way.

you dont extend them cause there is a disconnection...anyways..we might be all wrong hahahaha...

[bot6]

The idea is to make the diffuser "think" it's longer than it is by adding those foils at the back of it, so "extension" is a pretty good term to describe it.

But again, we seem to agree on the underlying physical effect of stabilizing and guiding the flow exiting the diffuser. The rest is just semantics.

[beelsebob]

The idea is to make the diffuser "think" it's longer than it is by adding those foils at the back of it, so "extension" is a pretty good term to describe it.

But again, we seem to agree on the underlying physical effect of stabilizing and guiding the flow exiting the diffuser. The rest is just semantics.

Nothing to do with stabilizing – just making it faster. The air gets pushed out behind the rear wheels, making the area behind the diffuser lower pressure, hence drawing more through the diffuser. Simple.

[bot6]

I think it also helps to isolate the diffuser itself from the turbulence caused by the spinning rear wheels. It might not be the main effect, but it certainly would help diffuser efficiency.

Also, if you look at the angle of those fins compared to the fences in the diffuser, the "cheese grater" seems to be accompanying the flow out of the diffuser more than really turning it. Considering the chord and span of those little foils, I doubt they have enough area to effectively change the direction of the flow, which is why I think they are mostly there to guide and stabilise rather than bend the airflow.

[alelanza]

you dont extend them cause there is a disconnection...anyways..we might be all wrong hahahaha...

What disconnection is that?

[LotusF1]

you dont extend them cause there is a disconnection...anyways..we might be all wrong hahahaha...

What disconnection is that?

they are connected to the rear wing but disconnected to the diffuser...so they are not an extension of the diffuser fences, rather a low pressure zone to increase velocity and hence extration to the diffuser..

[Caerdroia]

you dont extend them cause there is a disconnection...anyways..we might be all wrong hahahaha...

What disconnection is that?

they are connected to the rear wing but disconnected to the diffuser...so they are not an extension of the diffuser fences, rather a low pressure zone to increase velocity and hence extration to the diffuser..

They "effectively" extend the sidewalls of the diffuser, not literally.