2012 Exhaust Blowing & Coanda

[Adrian Newby]

Adrian Newey is a genius because of CHARLIE WHITING

[Crucial_Xtreme]

Adrian Newey is a genius because of CHARLIE WHITING

Awesome avatar bro!!

@Bhall Just blame it on lack of sleep from the concert )

[Adrian Newby]

Thanks. I was actually inspired by yours, and thought I should put one up too.

[shelly]

Forgot to write - add me too to the "rbr are trying to blow along the footplate edge" party", please.

[bhall]

[My comments made much more sense within the context - and thread - in which they were posted. In the future, please delete my comments outright if they're summarily deemed immaterial to their respective discussions rather than move them and render the thoughts completely neutered. Thank you.]

[Crucial_Xtreme]

@Bhall Just blame it on lack of sleep from the concert )

Concerts. It was a veritable Radiohead Week here in Texas. (It's like spring break, but without all the people I hate.)

But really, if you look at the two pictures I posted last night (or this morning), there are indications that the exhaust is in no way localized to one area at the back of the car. Rather than recognizing the admitted reality that Red Bull hasn't quite gotten the setup right just yet, I assumed my initial theory was wrong.

If you've ever been around women for any length of time at all, you'll understand such a reflex.

You heading to SXSW??

I've been married for 11 years & have a daughter so I'm familiar with women. To your point, I think what you said about the flow not being localized is correct. Some of us have always believed it did one thing at low speeds & another at high speeds. Also I read an article on NextGen Auto where an engineer from a rival team said it was apparent that their new exhaust solution wasn't doing/going where they intended it to. Although I'm sure Newey will have worked on that since the last Barcelona test.

[bhall]

[My comments made much more sense within the context - and thread - in which they were posted. In the future, please delete my comments outright if they're summarily deemed immaterial to their respective discussions rather than move them and render the thoughts completely neutered. Thank you.]

[Pup]

Wonder how long it will be before Red Bull try this solution. They are half way there already.

Emitting an orange death ray out of the exhaust? I'm sure he's tried.

[Adrian Newby]

Seb requested this after Montreal last year.

[MIKEY_!]

but seriously, slots in the curved surface beneath the exhaust exit. Discuss further here viewtopic.php?f=6&t=11604

[hardingfv32]

Forgot to write - add me too to the "rbr are trying to blow along the footplate edge" party", please.

Last year we had the exhaust forming a vortex at the diffuser/footplate edge. I believe the low strake in front of the inside edge of the rear tire is there to form a vortex using the flow around the side pod. It is not possible to get the exhaust flow in line with this axis of this strake to help improve the vortex formation.

What does the flow do when it gets to the edge of the diffuser? How is it made to do something useful? How does it seal the diffuser? Why route it there if you can not demonstrate value?

Why route more flow to an area that is already leaking to the underside of the diffuser?

Back up your opinions with some details.

Brian

[bhall]

[My comments made much more sense within the context - and thread - in which they were posted. In the future, please delete my comments outright if they're summarily deemed immaterial to their respective discussions rather than move them and render the thoughts completely neutered. Thank you.]

[Adrian Newby]

but seriously, slots in the curved surface beneath the exhaust exit. Discuss further here viewtopic.php?f=6&t=11604

I guess it would depend on where the slots lead, and where we are on the "ingestion" issue.

[hardingfv32]

Where does this 5 m/s figure come from? Sorry, I don't feel like trawling through 20 pages to find it.

Specifically:

1. Where did the number come from?
2. Is it real?
3. At what speed/rpm is this figure valid?
4. At what distance is it valid?
5. Is this figure specific to the RB8?
6. Is it different than last year's relative exhaust velocity? Specifically how so?
7. Why can't a small relative difference still be beneficial?
8. Why can't something that worked so well last year not work this year?

kilco316's calculation for exhaust flow velocity at the 18000 rpm, VE 125%, 200 C exhaust tip temp, 755 HP, 2.4 L, BSFC .5 is 84 m/s.

Car speed is 64 m/s, so I average the two flows to get 74 m/s shortly after the exhaust flow has left the tip. Based on s smikles sim observation that the exhaust losses velocity on its way to the, I reduced the 10 m/s gain by a conservative 50% to get 5 m/s. These numbers are a non specific to an make. Actually not concerned with specific flow other than the fact that they are 64 m/s when they meet the exhaust. I do not need make specific data to demonstrate the numbers.

There is no reason the exhaust tip velocity would be any different this year.

Of coarse very little tiny bit of improvement matters. But this years limited exhaust benefit might create more benefit blowing the wings, etc. as opposed to the diffuser edge.

Now it is time to show your calculations! What have you got?

Brian

[hardingfv32]

Intelligence is not knowing everything, but knowing where to find it.

You are sure about that? None of your sources provide any detail about how this is accomplished. Just more opinion which we have plenty of already. Intelligence is developing a working model for your theory.

'What does the flow do when it gets to the edge of the diffuser? How is it made to do something useful? How does it seal the diffuser? Why route it there if you can not demonstrate value?

Why route more flow to an area that is already leaking to the underside of the diffuser?

Back up your opinions with some details.'

Brian