[MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

Post here information about your own engineering projects, including but not limited to building your own car or designing a virtual car through CAD.
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variante
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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I think the 2D analysis has huge problems. The 3D wing will be too short to properly represent the ideal case, and it will also strongly interact with other bodywork elements.

When i try a new front wing and don't have the time to test the whole car (which is otherwise highly recommended), i make a simplified version of the 3D wing: a short extrusion (about as wide as the actual thing) placed at the right height from the ground, a simple endplate and the entire front wheel. I would not simplify further.

As for the rear wing, i make and test the actual complete rear wing with endplate, just without the rest of the car.

And still, you might experience big variations between these simplified cases and the whole car test, such that what performed best in the simplified cases could become one of the worst candidates for the actual car.

As for what airfoils to choose, i'd say don't do that. Just think about what shape the entire wing is supposed to have, then break it into as many sections as flaps you intend to use and, finally, design bespoke flaps.
Designing and coupling airfoils on your own requires an algorithm, a reliable method, and also some intuition and experience (which you can build up in the process anyway). If you think you can do it, it's worth doing it.

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jjn9128
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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There are no aerofoil families (that I know of) which are designed to be used inverted and in ground effect.

Also while wing shaped the front wing is so dominated by the Venturi effect it's got more in commmon with a diffuser.
#aerogandalf
"There is one big friend. It is downforce. And once you have this it’s a big mate and it’s helping a lot." Robert Kubica

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Salamander
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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Thanks for the info guys! It's appreciated, I will take it into account.

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LVDH
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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So, I think to have fixed the issue. You can now download the new version. It is pretty late so I cannot run the final tests now. Let me know if it works.

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yinlad
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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LVDH wrote:
Thu Apr 16, 2020 8:32 pm
So, I think to have fixed the issue. You can now download the new version. It is pretty late so I cannot run the final tests now. Let me know if it works.
I tried post processing a test case with the new version today and it got stuck in a loop as far as I could tell. But I had built it on a previous version, so that might be the issue. I'll try it out on a test case that was built using the 2004 client tomorrow
MVRC - Panthera

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AratzH
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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I tried the new version and the post processing pictures still go into the root folder, one level up from the case folder.
Also, for some reason sometimes I get the U_nearWalls VTK and pictures but other not. Apparently there is some error while sampling some parts:
Time = 2500

Reading fields:
volScalarFields: static(p)_coeff total(p)_coeff
volVectorFields: U

Executing functionObjects
--> FOAM Warning :
From function void Foam::mappedPatchBase::calcMapping() const
in file mappedPatches/mappedPolyPatch/mappedPatchBase.C at line 604
Did not find 24052 out of 23575 total samples. Sampling these on owner cell centre instead.
On patch wheel_fl on region region0 in mode nearestCell
with offset mode normal. Suppressing further warnings from mappedPatchBase
[9] Generating stack trace...

Any ideas?

Also, small sneak peak:
Image
MVRC -> TF

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Koldskaal
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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AratzH wrote:
Sat Apr 18, 2020 2:56 pm
I tried the new version and the post processing pictures still go into the root folder, one level up from the case folder.
Also, for some reason sometimes I get the U_nearWalls VTK and pictures but other not...
Same for me. I built, ran and postprocessed the case in Mflow 2004
MVRC - Koldskaal, name: Christian

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machin
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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AratzH wrote:
Sat Apr 18, 2020 2:56 pm

Also, small sneak peak:
https://i.imgur.com/E5nUSaO.png
Looks good! I know it’s work in progress, but just in case; rear wing central supports appear to be missing... 😉
COMPETITION CAR ENGINEERING -Home of VIRTUAL STOPWATCH

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jjn9128
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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I must admit to being rather stumped by this competition. I'm struggling to produce even half the downforce I would and have generated with a "proper" F1 car in the past. Is there some trick I'm missing?!? Some "cheat" as it were in the software?!

Image
#aerogandalf
"There is one big friend. It is downforce. And once you have this it’s a big mate and it’s helping a lot." Robert Kubica

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variante
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Location: Monza

Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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I think the way MFLow is set allows for nice realistic sims, but that also means that our hopes for easy performance gains should be abandoned.
On the other hand, bodywork elements that don't work well together will make your experience huge performance losses. Your car looks nicely designed already, and version 6 would surely score good points (assuming balance is ok), but are you sure you need for example bargeboards or outwashing endplates? do they actually work well with your diffuser, etc.
And since we have a similar FW approach, have you tried my design (because i tried yours and i wasn't as happy)?

BTW i'm struggling a lot too, if that reassures you, but my problem is drag and efficiency at low downforce levels. I can't see myself winning at Monaco right now, given how efficiency oriented it is (surprisingly).

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jjn9128
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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variante wrote:
Sun Apr 19, 2020 1:44 pm
Yeah maybe, but I'm not happy :lol: green line is L/D=2 and I want to be nearer there.

Maybe I'll have to play with the front wing again but I'm generating enough downforce to balance the car right now. Did you post a pic here or is it in 2019?
#aerogandalf
"There is one big friend. It is downforce. And once you have this it’s a big mate and it’s helping a lot." Robert Kubica

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variante
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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jjn9128 wrote:
Sun Apr 19, 2020 5:03 pm
Did you post a pic here or is it in 2019?
Check out my thread ([MVRC] Variante) in Engineering.

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jjn9128
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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variante wrote:
Sun Apr 19, 2020 5:46 pm
jjn9128 wrote:
Sun Apr 19, 2020 5:03 pm
Did you post a pic here or is it in 2019?
Check out my thread ([MVRC] Variante) in Engineering.
Yeah I saw it after is asked the question #-o

Your's is always beautiful modelling. Mine's a bit 2-d by comparison.
#aerogandalf
"There is one big friend. It is downforce. And once you have this it’s a big mate and it’s helping a lot." Robert Kubica

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wb92
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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jjn9128 wrote:
Sun Apr 19, 2020 5:54 pm
Your's is always beautiful modelling. Mine's a bit 2-d by comparison.
as long as it works and makes the car quick - doesn't matter how ugly/beautiful it is, and it's also matter of everyone's taste :)
jjn9128 wrote:
Sun Apr 19, 2020 11:53 am
I must admit to being rather stumped by this competition. I'm struggling to produce even half the downforce I would and have generated with a "proper" F1 car in the past. Is there some trick I'm missing?!? Some "cheat" as it were in the software?!
hi5! I have to say that I really hoped for ground effect cars as current rules drive me bit crazy with my car, it was supposed to be small revolution, but seems like the 'r' will be gone, at least the whole model is built in more modular and parametric way, so it's way easier to handle.
AratzH wrote:
Sat Apr 18, 2020 2:56 pm
Also, small sneak peak:
Image
looks clean and tidy.
seems like outwash front wings are going to be the thing again...?
variante wrote:
Thu Apr 16, 2020 11:07 am
I think the 2D analysis has huge problems. The 3D wing will be too short to properly represent the ideal case, and it will also strongly interact with other bodywork elements.
2D analysis of multi-element wing profile will give you feeling how to build profiles one-on-top-of-another, especially if one will manage to do plenty of parameter sweeps like angle of attacks, gaps, overlays, chordline lengths. Will work for both front and rear wing, of course until certain extense. In the end the whole wing has to be tested in full car setup.
jjn9128 wrote:
Thu Apr 16, 2020 11:25 am
There are no aerofoil families (that I know of) which are designed to be used inverted and in ground effect.
In general no, but one can start with high-lift airfoils, and some thin airfoils as a base for further modification.
To build them in parametric way in CAD or any 3d software there are few methods described out on the internet, no need to lay on exact points of "the airfoil" if it's gonna be changed next day :)
MVRC - WBRacing

Joe7218
Joe7218
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Re: [MVRC] Mantium Virtual Racecar Challenge 2020 (Grand Prix Cars)

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Bit confused with this rule,
"6.1.3 Must be located within the bodywork volume at a point 1540mm rearward of the FWCL, and 700mm above the reference plane."
Does that mean the bottom of the engine inlet surface must be 700mm above the reference plane? or is it a minimum of 700mm?
Thanks