Correlation between CFD and wind tunnel results

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ESPImperium
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Joined: 06 Apr 2008, 00:08
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Re: Correlation between CFD and wind tunnel results

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Ferarri Tunnel #1:

Image

McLaren Tunnel:
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Mercedes Tunnel #1:
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Mercedes Tunnel #2 (Hispania Tunnel):
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Renault Tunnel:
Image
Image
http://www.heatonplanning.co.uk/service ... /pc188700/

Williams Tunnel:
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Force India:
They now use a Airbus wintunnel in Liverpool seemingly, they used to go to Formtech when with Mike Gasgoyne.

Sauber:
No Pics avalable

Red Bull/Toro Rosso:
No Pics Avalable

Toyota:
Image

Team Lotus:
Currently use Formtech, but a tunnel in Hingham, Norfolk is in the planning stages for Team lotus.

Virgin:
Plenty of ones and zeros.

PNSD
3
Joined: 03 Apr 2006, 18:10

Re: Correlation between CFD and wind tunnel results

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hardingfv32 wrote:PNSD - Wind tunnel design

How do they get .0001% accuracy in a wind tunnel? I can barely fined a .001% force measuring device. Would this also mean the the airflow in the tunnel must be maintained at .0001% or at least measured to that accuracy? With total accuracy at .0001%, that would mean all the individual tolerances of the system must be lower. How is this possible?

Brian
Perhaps I worded it wrong, I mean Cd's could be calculated within 0.0001 Cd. It comes at a huge cost of course, and only few wind tunnels in the world will achieve such accuracy but its a rather large requirement to have such accurate Cd's when you consider fuel consumption.

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ringo
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Joined: 29 Mar 2009, 10:57

Re: Correlation between CFD and wind tunnel results

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You are talking about precision or error?
For Sure!!

czt
czt
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Joined: 05 Mar 2009, 00:07

Re: Correlation between CFD and wind tunnel results

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ESPImperium wrote: Force India:
They now use a Airbus wintunnel in Liverpool seemingly,
Do you have a source/ any more info for this?

ESPImperium
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Joined: 06 Apr 2008, 00:08
Location: Glasgow, Scotland
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Re: Correlation between CFD and wind tunnel results

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czt wrote:
ESPImperium wrote: Force India:
They now use a Airbus wintunnel in Liverpool seemingly,
Do you have a source/ any more info for this?
It was in the press release when they signed the aggreement in 2008.

Seemingly Force India get to use the tunnel at nights when the Airbus guys have gone home, and at weekends.

However, Force India have been looking at building a integrated CFD/Windtunnel building at Silverstone so as to give more space over to the engineers that build the cars in the single building they have at Silverstone.

If you have a look at the space arround the factory, they have the space, and the feild behind the factory is owned by the team, so it could go there. Force India are looking to expand, but all with in their means. Ideally they are looking for a facility that is as good as Williams Grove site, but over a fith of the area of land.

http://www.f1fanatic.co.uk/f1-informati ... a-f1-team/
(See the Google maps bit)

czt
czt
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Joined: 05 Mar 2009, 00:07

Re: Correlation between CFD and wind tunnel results

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You seem to have forgotten FI's tunnel in Brackley.

The use of an airbus tunnel is nonsense. It would be impractical to swap models and reconfigure a tunnel for use overnight. Do aerospace tunnels even feature the moving ground plane that a race car wind tunnel would require?

ESPImperium
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Joined: 06 Apr 2008, 00:08
Location: Glasgow, Scotland
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Re: Correlation between CFD and wind tunnel results

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Some aerospace tunnels have the rolling road for takeoff and landing sims, but generally no.

Seemingly they only use the access for about 5 or 6 days a year, not much, but enough for rough tests.

TURU
0
Joined: 31 Jan 2011, 21:26

Re: Correlation between CFD and wind tunnel results

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ESPImperium wrote:Ferarri Tunnel #1:
Renault Tunnel:
Image
http://www.heatonplanning.co.uk/service ... /pc188700/
I thought this is Renault's CFD facility.

marcush.
159
Joined: 09 Mar 2004, 16:55

Re: Correlation between CFD and wind tunnel results

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sauber windchannel pics:
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60% model:
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markc
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Joined: 08 Dec 2011, 01:30

Re: Williams FW34 Renault

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Megafactories (on Discovery) had a show on Williams F1, which I watched last night. It was rather enlightening: new front wing from design to car. Process: CFD -> wind tunnel -> Simulator -> go / no-go meeting -> Fabricate -> on car. In this case the car was FW33.

I was most interested to see that when they "fitted it" onto the car in the simulator it showed improvement (to previous wing), and that seemed to be the deciding factor in the go / no-go meeting. Fascinating.

Improvements were also confirmed in the wind tunnel model, so they weren't blindly taking CFD and simulator as gospel, but I would expect CDF and simulator to correlate. Same algorithms (I assume - and that could be my down fall!).

Anyway it was a fascinating show, and if you get the chance to watch I would recommend you do!

shelly
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Joined: 05 May 2009, 12:18

Re: Williams FW34 Renault

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Simulator takes data from windtunnel to simulate the behaviour and the laptime with driver in the loop.

It is a pipeline: cfd|windtunnel|simulator.

You can correlate cfd with windtunnel to some extent. Then the wind tunnel aero map(s) is fed into the simulator. I do not think they make aeromaps in cfd.

Simulator and cfd simulation are two completely different softwares, with very different hardware.
twitter: @armchair_aero

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markc
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Joined: 08 Dec 2011, 01:30

Re: Williams FW34 Renault

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Thanks Shelly very informative :)
Good point that hw and sw are different for CFD and Sim, but I assume (again and again it may be my downfall!) they follow the same/similar algorithm which would yield the same/similar results?

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horse
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Joined: 23 Oct 2009, 17:53
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Re: Williams FW34 Renault

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shelly wrote:Simulator and cfd simulation are two completely different softwares, with very different hardware.
Precisely, the simulator is not solving any CFD on the fly. It is taking the aggregated data predicted by the CFD and validated in the wind tunnel and applying that to the dynamic model of the car.

I would doubt that something like a front wing could be done in isolation as it has a strong impact downstream. I guess they would have to get data for the entire car and provide it to the simulator.
Ringo wrote:Williams need a new front wing, this sliced fruit looking wing can't cut it.
I was really surprised to see the thing on the car. Its development came from issues with the Cosworth engine and diffuser blowing, two problems they don't have any more.
"Words are for meaning: when you've got the meaning, you can forget the words." - Chuang Tzu

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FW17
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Joined: 06 Jan 2010, 10:56

Re: Correlation between CFD and wind tunnel results

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How long does each wind tunnel session last?