Exhaust Blown Floor - Forward Exhaust Exit

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Formula None
Formula None
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Joined: 17 Nov 2010, 05:23

Re: Exhaust Blown Floor - Forward Exhaust Exit

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marekk wrote:It's my pure speculation, so i could be totaly wrong of course.

We've discused already how the cooling gases under the floor add to cars downforce and i still stand by my ideas with this.

We should not forget this car is desgined and built for RK, and his strenghts are/was very late, hard breaking and good feeling for mechanical grip - so i can see benefits from high downforce (without high drag) at the end of the straights for R31/Kubica package.

Following few snapshots of Petrov's run in FP1 - just after turn 8, moer or less one second apart.

I can clearly see water spray from front right tyre disapearing under the floor as the car accelerates (first 2 stills even show some bending of flowlines due to FEE IMO):

Image

Seems similar in this photo. Granted, one photo taken at one speed so make of it what you will.

Image

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ringo
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Joined: 29 Mar 2009, 10:57

Re: Exhaust Blown Floor - Forward Exhaust Exit

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shelly wrote:I disagree with you ringo.
I do not think scarbs informers have put him delibarately on a wrong track, as you do.
I have read some post from SLC and they show a deep understanding of modern f1 aerodynamics; remember also that at the beginning he mocked this forum, saying that his colleagues and him used to laugh at the comments of the people in it.
I believe he has worked in f1 in the past and now is still in aero in another industry.

As far as reasonable proofs, for the moment we lack them: images do not show much.
Even if we had a professional level cfd run we still would not have conclusive evidence.
I don't like to blow my own horn, but i have a logical understanding on what is happening. I am confident scarbs was misinformed or he simply took the information and interpreted it differently.
As for SLC he never said he worked in an F1 team or as an aero guy.
Reading his posts, i don't get that level from him, and i should know. But as i say i don't like to toot my own horn; when i do i get warned. :lol:

I realize it makes no sense to go to a deeper level, becuase it doesn't matter. I don't have a website and i don't post with brovado.
There is logic as to why the gas don't go under, but i'll hold out becuase i am enjoying the discussion.
The Bible says not to toss your pearls to the swine. So just like the high nose debate from 2010, i'll hold out until it becomes plainly obvious.

Just like the blown starter hole nonsense! :lol:
For Sure!!

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ringo
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Re: Exhaust Blown Floor - Forward Exhaust Exit

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So again i ask, why does the gas not go under the diffuser at turning speeds ?

Explain the logic of Renault making the gas go under on the straight; which is doesn't ?

Why is it wider in the corner and not under the car?

I await a logical response to this conundrum. And it's only a conundrum becuase the shoes don't fit the theory.
For Sure!!

shelly
shelly
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Joined: 05 May 2009, 12:18

Re: Exhaust Blown Floor - Forward Exhaust Exit

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Ringo, do not create by yourself contrdictions you are not able to explain!

About SLC: he wrote in this forum he was working for a leading f1 team in 2006.
His comments are very spot on and prove he has single seater aerodynamics knowledge. I find it surprising that you have not checked Slc posts and seen it yourself.

As far as your question: why does the gas not go under the diffuser at turning speeds, it is just you saying that it does not. So you are creating by yourself a contradiction. Gases do go under the diffuser.
I think that you are misleaded by the cad pictures you posted, you seem to believe in the flow patterns you see there.
twitter: @armchair_aero

bcoxa
bcoxa
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Joined: 11 Aug 2009, 09:59

Re: Exhaust Blown Floor - Forward Exhaust Exit

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ringo wrote: I realize it makes no sense to go to a deeper level, becuase it doesn't matter. I don't have a website and i don't post with brovado.
There is logic as to why the gas don't go under, but i'll hold out becuase i am enjoying the discussion.
The Bible says not to toss your pearls to the swine. So just like the high nose debate from 2010, i'll hold out until it becomes plainly obvious.

Just like the blown starter hole nonsense! :lol:
Contradiction much?
I'm not an engineer, just an experiment.

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ringo
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Joined: 29 Mar 2009, 10:57

Re: Exhaust Blown Floor - Forward Exhaust Exit

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What do you mean?
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Just_a_fan
Just_a_fan
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Joined: 31 Jan 2010, 20:37

Re: Exhaust Blown Floor - Forward Exhaust Exit

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ringo wrote:[As for SLC he never said he worked in an F1 team or as an aero guy.
Reading his posts, i don't get that level from him, and i should know. But as i say i don't like to toot my own horn; when i do i get warned. :lol:
Which F1 team do you work for?
If you are more fortunate than others, build a larger table not a taller fence.

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ringo
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Joined: 29 Mar 2009, 10:57

Re: Exhaust Blown Floor - Forward Exhaust Exit

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I don't work for any f1 team. I'm just a so-so engineer. Though i wish i did work in an f1 team.
Fluid dynamics exists outside of F1 too. So based on what someone says, it's possible to discern how much they know about what they are saying. SLC may be an engineer as well, but to assume he's a past F1 engineer when he never said so can be misinforming. And even then not all F1 engineers will be strong at fluids.

What i am confident in though, is that journalists can't tell me about my field, they can only relay direct information from the engineers themselves. So without direct evidence or quotes, it's only a shot in the dark to appease their readers.
Which isn't totally bad, because sometimes it's close enough and better than nothing.

Renaut will not tell anyone where the exhuast is going, they just wont. They may only say it increases the downforce. Until another team copies it and it works then they'll talk.

A real hint that it's blowing outward though, came from the chinese engineer in the team. He mentioned in a video that the downforce is more centralized. This suggest that the target is the floor and not the diffuser, as the diffuser is out the back and not in the middle of the car.
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PNSD
PNSD
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Joined: 03 Apr 2006, 18:10

Re: Exhaust Blown Floor - Forward Exhaust Exit

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IIRC SLC did say he worked for an F1 team, and on numerous occasions it was bought up?

And again, as SLC said, wasnt the FEE just to increase the suction peak at the floor rather than diffuser?

BreezyRacer
BreezyRacer
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Joined: 04 Nov 2006, 00:31

Re: Exhaust Blown Floor - Forward Exhaust Exit

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PNSD wrote:IIRC SLC did say he worked for an F1 team, and on numerous occasions it was bought up?

And again, as SLC said, wasnt the FEE just to increase the suction peak at the floor rather than diffuser?
To clarify all diffusers are created for the same thing .. to increase "suction" (AKA low pressure) under the floor. Down force is not created in the diffuser box, but rather on the surface of the floor ahead of the diffuser box.

How far ahead and under what variances of ride height, pitch, and yaw is dependent on how good the design is.

PNSD
PNSD
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Joined: 03 Apr 2006, 18:10

Re: Exhaust Blown Floor - Forward Exhaust Exit

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Then allow me to clarify my post. By floor, I meant the entry of the floor, and initial the suction peak.

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Fil
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Joined: 15 Jan 2007, 14:54
Location: Melbourne, Aus.

Re: Exhaust Blown Floor - Forward Exhaust Exit

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:oops: EDIT: Within 5min of uploading, I received an email from Youtube re copyright.. what do i need to edit in the vid to bypass this? PM me if this is too off-topic.
Last edited by Fil on 10 May 2011, 05:07, edited 1 time in total.
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Any fact(s) claimed by this user will be supplemented by a link to the original source of said fact(s).

Speeed24
Speeed24
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Joined: 09 May 2011, 04:21

Re: Exhaust Blown Floor - Forward Exhaust Exit

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There is some obvious visual evidence that the FEE isn't designed to feed the rear diffuser:

1) The exhaust isn't pointing backwards... if they wanted to feed the rear diffuser it would point directly backwards. Anyways this wouldn't be a good idea and would probably cause mass to build up under the floor as the rear diffuser efficiency on current F1 cars depends on the mass flow out of the larger rear exit.

2) The upwards pointing "lip" on the side of the floor. Why design the floor to guide the flow out and to the side if you want the flow to reach the rear diffuser?

I also don't think it creates additional downforce on the front sides of the floor since it is adding transverse (to the motion of the car) velocity to the fluid.

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Pierce89
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Joined: 21 Oct 2009, 18:38

Re: Exhaust Blown Floor - Forward Exhaust Exit

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Just_a_fan wrote:
ringo wrote:[As for SLC he never said he worked in an F1 team or as an aero guy.
Reading his posts, i don't get that level from him, and i should know. But as i say i don't like to toot my own horn; when i do i get warned. :lol:
Which F1 team do you work for?
Scarbs we can all admit has more F1 connections than any of us and wrote that he was told by a team employee that SLC is an aerodynamicist working in industry. I personally belive it because i searched SLC old posts and his aero knowledge easily dwarfs anyone else here.
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strad
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Joined: 02 Jan 2010, 01:57

Re: Exhaust Blown Floor - Forward Exhaust Exit

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I thought we had agreed that the exhaust gasses form a layer at the outer edge that mimics skirts?????
I still would like some mechanic that lives in the real world to explain to me how you can make power whilst purposely hanging the exhausts open.
I have my own theory but ......
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