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Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 02:50
by julien.decharentenay
Hi Gents,

The KVRC 2014 Monza Race are out - one day late due to health issues... Sorry about this.

The result page http://www.khamsinvirtualracecarchallen ... 14/results has been updated to include the latest result. Congratulation to CSR for his outstanding performance and Variante for consistently great design and all participants for your participation and efforts..

The race visualisation will be available soon and the team tally will be updated on the website home page. The current point count is (Luke will confirm):

CSR: 68 Points
Variante: 61 Points
JJR Racing: 42 Points
CAEdevice: 36 Points
BigSpace Racing: 31 Points
Team Furia: 26 Points
Bleeding Edge: 14 Points
Cottrell Motorsport: 4 Points
Kulcu Motor Sports: 0 Points

The CFD results and a peak at designs through the short YouTube video: http://youtu.be/yyrEYZfveY8

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 07:07
by machin
julien.decharentenay wrote: The CFD results and a peak at designs through the short YouTube video: http://youtu.be/yyrEYZfveY8
Cool Video!

Well done guys... everyone did a good job at getting the drag right down for Monza.... now to get the downforce up for Silverstone!

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 08:24
by hollus
Watching that video... is it me or are the Monza results basically ordered by angle of attack of the rear wing, with the flattest winning and the tallest losing?

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 08:39
by astracrazy
that will be the case. The lowest drag performs better here, but you still need some downforce. So the most efficient cars can go all out at reducing the rear wing and still maintaining some level of competitive downforce whilst others still need a slightly higher aoa (hence leading to higher cd.a)

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 09:36
by CAEdevice
astracrazy wrote:that will be the case. The lowest drag performs better here, but you still need some downforce. So the most efficient cars can go all out at reducing the rear wing and still maintaining some level of competitive downforce whilst others still need a slightly higher aoa (hence leading to higher cd.a)
Yes, I agree. If you consider CSR and Variante, they were able to use low downforce (CSR almost without rear wing) with an acceptable balance (COP). I could have choosen a smaller rear wing (I tested a car with a Cd.A value of 0,7!!!) but I would have had a COP value of 1,2m... The reason is that CSR and Variante at the moment have to most high floor and diffuser downforce: congratulations to both for the excellent work!

I think that JJR could be competitive at the same level as CSR and Variante in tracks that require high downforce setup.

CAEdevice, BigSpace and Furia instead needs to work on floor efficiency in my optinion, but now we all have a quite rational car shape to develop.

Sorry for the DNS of three teams.

Hope that health iusses has been solved, thanks to Astracracy and Julien: very good job as always!

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 10:10
by astracrazy
Image
Image

Just to bring the graphs to the front

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 10:18
by CAEdevice
I'm happy with my 4th place, but after 4th/4th/4th its time to try something more (o less!) :)

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 12:08
by RicME85
Yeah, completely missed the submission date, lost all track of days.
Annoying as I had a whole new car for the race.

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 16:02
by variante
Another impressive performance from CSR! And nice to see improvements from all the other guys

I have faced a huge "correlation issue" between my CFD results and official ones. My fault. I'll improve my calculations and CFD settings for the next round.
I might have one or two bullets to shoot, but i'm likely to miss the target... The car was developed in order to achieve the maximum downforce without compromises...compromises that i should have looked for...

And sorry if i'm not participating to the conversation, but i'm very busy these days... Anyway, i'm open to your proposals.
I think that the "F1" formula has some space left for us to develop the cars and exploit the regulations, and it's also the most fascinating one. However i find as fascinating to reinterpret old formulas taking advantage of contemporary knowledge (as suggested earlier).


BTW...the video was awesome :D

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 28 Apr 2014, 22:18
by machin
I've updated the chart showing all the Cl.A and Cd.A figures from the cars so far.... no real "pushing of the boundaries" this round, lets see what you guys can do for Silverstone.....

Image

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 30 Apr 2014, 11:13
by CAEdevice
Maybe it's already been linked, but it is an interesting article:

http://eprints.soton.ac.uk/42969/1/GetPDFServlet.pdf

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 30 Apr 2014, 14:53
by cdsavage
Well done everyone on round 3. The video was neat, how was that done? Were the three meshes merged somehow? Looked like it was still within paraview.
machin wrote:I've updated the chart showing all the Cl.A and Cd.A figures from the cars so far.... no real "pushing of the boundaries" this round, lets see what you guys can do for Silverstone.....
True, but with larger sidepods, a narrower front wing and no beam wing, efficiency was always going to be more difficult to achieve at monza compared to the 2013 cars.

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 30 Apr 2014, 15:43
by CAEdevice
cdsavage wrote:Well done everyone on round 3. The video was neat, how was that done? Were the three meshes merged somehow? Looked like it was still within paraview.
machin wrote:I've updated the chart showing all the Cl.A and Cd.A figures from the cars so far.... no real "pushing of the boundaries" this round, lets see what you guys can do for Silverstone.....
True, but with larger sidepods, a narrower front wing and no beam wing, efficiency was always going to be more difficult to achieve at monza compared to the 2013 cars.
I was wondering if "real F1" data were referred to 2013 or 2014.

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 30 Apr 2014, 21:22
by machin
cdsavage wrote: with larger sidepods, a narrower front wing and no beam wing, efficiency was always going to be more difficult to achieve at monza compared to the 2013 cars.
I think everyone did a much better job in 2014 than 2013 at Monza; much lower drag in general this year, which led to faster lap times.

My comment was aimed at comparing the Monza and Magny Cours 2014 results; you can see that the Monza results didn't improve the "best limit" line (i.e. if you take away the Monza results the "best limit" line wouldn't change), although your result did allow the curve to be extended further back along the Cd.A axis (without changing the gradient). =D>

For Silverstone it would be great to see if anyone can push the best limit line down at higher downforce levels.... (moving the best limit line down indicates an improvement in efficiency).

CAEDevice wrote:I was wondering if "real F1" data were referred to 2013 or 2014.
That's 2013 data... and you have to take it with a pinch of salt; nobody gives away real data, but you can pick up things from interviews such as "Cl is in the region of 3 to 3.5", "Frontal area is about 1.3m^2", "Drag is approximately XXXX N at 100mph", etc... so the curve is just there as a guide.

Re: Khamsin Virtual Racecar Challenge 2014

Posted: 02 May 2014, 01:43
by julien.decharentenay
cdsavage wrote:Well done everyone on round 3. The video was neat, how was that done? Were the three meshes merged somehow? Looked like it was still within paraview.
Thanks a lot. The pictures are generated from paraview.

The first part - showing the 3 podium cars - was done by loading the 3 cases in a single scene (i.e not a mesh merging per say). Each case is translated so that they appear next to each other - I also translated them in the stream direction (y) by a nominal amount. A cut is created for each case and clipped to ensure that it is only shown in the "relevant" portion of picture. As the video progress the cut is moved backwards (along with the camera). The pictures are generated using a python script - I will try to dig out the "latest" version and upload it to the KVRC website for anyone to use.

The script generates a set of picture. Movie Maker was used to generate the movie. Music is from the YouTube "free" music library.