Khamsin Virtual Racecar Challenge 2014

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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CAEdevice
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Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2014

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julien.decharentenay wrote:After the last race, I was thinking of trying to take the McLaren bodywork and try a few mods to test (and improve) my design skills and see what I might be able to do. I will try to document it as I go along to share the information as well as get others input.
You and Luke could use that bodywork (with appropriate wings for the high DF track of the last race) for the KVRC official team.

astracrazy
astracrazy
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Joined: 04 Mar 2009, 16:04

Re: Khamsin Virtual Racecar Challenge 2014

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Bit late for that now tbh

although interesting results. I wonder why it performed so badly?

On a side note, please have your say for the future https://docs.google.com/forms/d/1BJwn8U ... =send_form

cdsavage
cdsavage
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Joined: 25 Apr 2010, 13:28

Re: Khamsin Virtual Racecar Challenge 2014

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Good idea on the poll, looking forward to seeing everybody's opinions.

One change I would make for next year - this year I think it was really important to have the right setup for each track. I found myself spending the majority of my time from round 3 onwards testing on different downforce levels to see where the best laptime was. In round 2 I focused more on overall efficiency rather than looking at the setup and I lost that round mainly because I used too high a downforce level.

I found this to be a bit frustrating - while it's a realistic challenge, I think it would be better to have more of a focus on overall downforce and efficiency. This way more time is spent on design concepts and less on finding the right wing angles etc.

To achieve this I would use only 2 'tracks' for the downforce/drag/laptime calculation. The rounds can still be called anything, just assume that some require the same setup. I would keep the Monaco round for maximum downforce, then use a setup somewhere between this year's round 4 and round 5 for the majority of the rounds. If there were going to be 6+ rounds then also have a Monza round, but since low drag circuits make up a small percentage of the real F1 calendar, omitting this round completely is probably OK.

I suggest a setup between round 4 and round 5 because I think the round 2 / round 4 drag target this year was too low - when you look at the ideal drag levels from round 2 and round 4, and compare them to what we see at those tracks in the real world, there is clearly a problem. I dont think Machin's laptime calculator is off, but I am pretty sure the CFD settings we are using underestimates floor downforce significantly. Combine this with the blanked-off inlets, zero rake etc and the CFD numbers are probably well off where an equivalent real-world model would be. The real world accuracy isn't a problem here since it's the same target for everybody, but the laptime calculation should be shifted to account for this, so that the ideal setup makes sense.

If we're introducing fudge factors into the calculation then maybe we could also reduce the importance of the COP slightly - having COP input is necessary, but I find that rebalancing the car also takes time that could be spent working on downforce/drag and new concepts. I dont know about others, but I find this kind of rebalancing and tweaking to be time consuming and not particularly interesting.

I'll post my thoughts on what I think we should do with the rulebook later, but it would be good see what everybody else is thinking first.

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CAEdevice
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Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2014

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I don't agree with you about the setup refining for each track: the presence of very different tracks as Monza and Monaco was one of the most interesting things in my opinion.

I agree with you about the technical issues: I think that underfloor DF is bit underestimate (15%).

For the next year assuming (and hoping) that the cars will be F1 like, I would suggest to take in cosideration:

1) Floor rake (the same value for all the cars)

2) Simplified internal sidepods flow (without involving porous models, I have some ideas about it)

3) A standard car to be used in case of problems to update the official one in the right time, to avoid DNS classification

4) A few additional detail rules: the rear view mirror position should be more realistic, the same for the airscope inlet and the floor and diffusee minimum thickness.

A last obseevation: I read that someone think that a less ruled formula would help creativity. I really don't think so: during the challenge I could realise less then half the ideas I had and if I compare Variante and CDSavage car to my car it is clear that I have so much work to do (and my car is classified at the 4th place, not so bad).

astracrazy
astracrazy
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Joined: 04 Mar 2009, 16:04

Re: Khamsin Virtual Racecar Challenge 2014

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I noticed myself that downforce from the floor isn't enough. I think this could be down to two things (Julien's input would help here too)

height - we kept the cars height from the ground from last year the same, but we are running smaller mesh sizes this year so should of looked into lowering the cars

rake - we haven't got any rake on the cars which will also make a difference, but we need to be careful how this can be applied.

I also think inputs and outputs should be indented by about 10mm to recreate the drag effect. Internal aero could, may, be possible but I worry about making sure its done properly

I can see where Chris is coming from with his comments about the tracks, it did seem and I found, wing set up seemed to be the big difference. It would be good to get peoples opinions on what they found throughout the season - did they feel there performance come from there wing set up or more from updates. Do we fix this problem by keeping to 1 or 2 tracks or is it an issue with the overall set up? Julien and Machin's thoughts would help us here.

One thing we will have going forward is some research cfd time available to us which i have spoke to Julien about. So whatever is decided going forward and suggestions made, we can test.

julien.decharentenay
julien.decharentenay
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Joined: 02 Jun 2012, 12:31

Re: Khamsin Virtual Racecar Challenge 2014

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Can you confirm that the submission portal is working? It is Thursday evening for me (ie still quite a few hours left to submit, but less than a day), and only one team - BigSpace Racing - submission has made its way into the system. Let me know if there is an issue...

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CAEdevice
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Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2014

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I'm going to upload my car in half an hour, I'll let you know if everything works

astracrazy
astracrazy
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Joined: 04 Mar 2009, 16:04

Re: Khamsin Virtual Racecar Challenge 2014

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and we got it ok

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CAEdevice
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Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2014

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yes the upload and the confirmation were fast, everything seems to work perfectly, except the keyboard of my smartphone...

I'm ready for another 4th or 5th place... but this version of my MP001 is a big improvement and I hope it will bring results next year.

In the meanwhile I guess I'll miss the KVRC in the next weeks.

julien.decharentenay
julien.decharentenay
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Joined: 02 Jun 2012, 12:31

Re: Khamsin Virtual Racecar Challenge 2014

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Looks like the portal is working. We have received the following to-date:
- BigSpace Racing;
- CAEdevice;
- JJR Racing;
- Variante;
- CSR.

Let Luke and I know if we are missing anyone.

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CAEdevice
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Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2014

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astracrazy wrote:Bit late for that now tbh
although interesting results. I wonder why it performed so badly?
Do you refer to te McLaren model? I think that there are differences with KVRC cars: for example it's quite different to draw a sidepod that has to really work (active inlet/outlet) than a side pod that just "divide" the air flow between upper and lower part of the car body, and the same for other details (rear view mirrors, ... ). Also consider that that model was designed to work with a minimum but not zero rake.

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CAEdevice
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Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2014

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julien.decharentenay wrote:Looks like the portal is working. We have received the following to-date:
- BigSpace Racing;
- CAEdevice;
- JJR Racing;
- Variante;
- CSR.

Let Luke and I know if we are missing anyone.
I'm sorry about TeamFuria absence :(

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CAEdevice
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Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2014

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cdsavage wrote:One change I would make for next year - this year I think it was really important to have the right setup for each track. I found myself spending the majority of my time from round 3 onwards testing on different downforce levels to see where the best laptime was. In round 2 I focused more on overall efficiency rather than looking at the setup and I lost that round mainly because I used too high a downforce level.
A good compromise could be to use only three tracks, high DF (Monaco or Hungary), medium DF (to be decided), low DF (Monza or even Indianapolis :) ).

Before Magny Cours race I would have considered it a medium DF track ( http://www.formula1.com/news/features/2007/6/6356.html ), but looking at the results it seems to be a low DF track. Maybe that tere is something that must be corrected (for example: I think that with a very low downforce level, there could be problems with tyres temperatures and traction/wear). It would be great to have a simplified tyre physical model next year... I can think about it since there are many months to develop it.

astracrazy
astracrazy
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Joined: 04 Mar 2009, 16:04

Re: Khamsin Virtual Racecar Challenge 2014

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A good compromise could be to use only three tracks, high DF (Monaco or Hungary), medium DF (to be decided), low DF (Monza or even Indianapolis :) ).
the tracks are limited to the data available i.e what machin has. We could get a full list from him and pick off that later down the line
Before Magny Cours race I would have considered it a medium DF track ( http://www.formula1.com/news/features/2007/6/6356.html ), but looking at the results it seems to be a low DF track. Maybe that tere is something that must be corrected (for example: I think that with a very low downforce level, there could be problems with tyres temperatures and traction/wear). It would be great to have a simplified tyre physical model next year... I can think about it since there are many months to develop it.
It is medium in F1 terms. But these cars aren't as efficient so are more drag restricted/affected so a low downforce set up is best.

Fully explained by machin on this page (4th down)
http://www.f1technical.net/forum/viewto ... &start=405

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CAEdevice
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Joined: 09 Jan 2014, 15:33
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Re: Khamsin Virtual Racecar Challenge 2014

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I've been testing the effects of a small rake: a small rake angle of 0,5° made the total downforce improve of 10% if applied to my Nurburgring car!

Consider that real f1 cars have rake that goes from 1° to 3° (even moro for Red Bull) and that the geometry I tested was not optimized considering the rake... I think that an improvment of the DF of 20% could be realistic.