Khamsin Virtual Racecar Challenge 2015

[julien.decharentenay]

It is the right time, but espcially the right day , to reveal some numbers:

https://dl.dropboxusercontent.com/u/522 ... il_1st.jpg

Matteo, did you edit the HTML file???

Thanks to all for submitting your design for this first race. Chris will be busy over the next few days to check compliance. Here is the plan for the next few days:

- Sunday 5th April (or earlier if possible): Notification of compliance or non-compliance of design;
- Tuesday 7th April: Deadline for resubmission for non-compliant design - please limit changes to area of non-compliance only;
- Thursday 9th April: Release of rendered images;
- Friday 10th April: Release of top and apex speeds - this will be down through twitter using the hash tags #simulationfriday and #kvrc
- Saturday 11th April (maybe): release of some walk-through/rendering;
- Sunday 12 April: release of results and race google map visualisation.

You will receive by email a link to download your own CFD results when these are available.

[CAEdevice]

It is the right time, but espcially the right day , to reveal some numbers:

https://dl.dropboxusercontent.com/u/522 ... il_1st.jpg

Matteo, did you edit the HTML file???

Thanks to all for submitting your design for this first race. Chris will be busy over the next few days to check compliance. Here is the plan for the next few days:

- Sunday 5th April (or earlier if possible): Notification of compliance or non-compliance of design;
- Tuesday 7th April: Deadline for resubmission for non-compliant design - please limit changes to area of non-compliance only;
- Thursday 9th April: Release of rendered images;
- Friday 10th April: Release of top and apex speeds - this will be down through twitter using the hash tags #simulationfriday and #kvrc
- Saturday 11th April (maybe): release of some walk-through/rendering;
- Sunday 12 April: release of results and race google map visualisation.

You will receive by email a link to download your own CFD results when these are available.

Interesting program!
I can't wait to see if anybody could really break the wall of Cd*A = 10 (my car is far from it).

About the April's fools: yes I edited the html

[crxdave]

Interesting program!
I can't wait to see if anybody could really break the wall of Cd*A = 10 (my car is far from it).

About the April's fools: yes I edited the html

I've got a long way to go to hit Cd*A=10!!

However, I managed to get OCCFD working for the first time today & ran my baseline spec. Whilst downforce is low, it looks like a good starting point & hopefully I can build on it.

Looking forward to the first race results

[CAEdevice]

Interesting program!
I can't wait to see if anybody could really break the wall of Cd*A = 10 (my car is far from it).

About the April's fools: yes I edited the html

I've got a long way to go to hit Cd*A=10!!

However, I managed to get OCCFD working for the first time today & ran my baseline spec. Whilst downforce is low, it looks like a good starting point & hopefully I can build on it.

Looking forward to the first race results

I'm looking forward too.
My Cl.A is much nearer to 5 than 10
Sometimes I had the suspect to have considered only half the car, but the simulation was correct. I'll be happy to confirm the usual 2014 4th place

[julien.decharentenay]

However, I managed to get OCCFD working for the first time today & ran my baseline spec.

Sometimes I had the suspect to have considered only half the car, but the simulation was correct. I'll be happy to confirm the usual 2014 4th place

@crxdave Glad to hear of your success. I would be keen to hear of feedback on what went wrong. I can try to add bits and pieces in the software to make it easier for others to use.

@CAEdevice Fingers crossed...

[CAEdevice]

Hi Julien, after a period during wich I have been busy with the car developing with another tools, I' going to test OCCFD again.

Compared to the first releases, now it is working better: I suggest the other partecipants to check that there are no internal surfaces and no holes (but internal surface, even if small, are more critical). It would be better to use high quality STL export (respecting the limit of 100Mb for the submission) and to avoid every round or geometry detail that is not influent on the CFD performance.

The COP seems to be correct now (I'm using the latest release, but I had no problems with it even with the previous release).

[julien.decharentenay]

The race is progressing well. This year design decisions are very interesting. Chris has checked compliance with the rules and notify participants of areas of non-compliance (if relevant). Participants with non compliance issues have a busy weekend ahead of them... But we have already seen some resubmission.

The CFD analysis for the compliant designs have been submitted last night. I am downloading the results this morning - I had to make a couple of modifications to OCCFD due to meshing issues. These modifications will be incorporated in an updated OCCFD version. For compliant participants, expect an email later today or tomorrow with a link to download your results - remember my previous notification on CoP. The link will download a .tar.gz archive, which you can extract using 7-zip. The download contains the openFoam results and a webpage (html) with result summary.

[CAEdevice]

I'm not compliant about the exhausts positioning... just like the previous years' Redbull

[variante]

Ok, so...i've just got my CFD report and, my bad, i anticipate that i haven't reached the Cl.A=10 target . Actually, i'm worringly far from that, as my rear wing (and my rear end in general) doesn't work as it should, for reasons that i've yet to understand.

On the other side, the front end works exactly as predicted; the rest of the bodywork is in line with predictions as well, while the general performances are still competitive. Let's wait for race results!

Any news from the KVRC guys?

[RicME85]

Rear end not working like mine?

[variante]

Rear end not working like mine?

Not quite: my diffuser is working...let's say 90% of what was predicted. The main problem is the rear wing(s); for example, yours is working much, much better than mine, especially on the underside. It could be due to front wing interference, but the problem is to big, so i don't think that's the only cause... It's basically not working... (and it's a well studied wing, trust me)

[RicME85]

Odd, my rear wing is the one from the KVRC car that Chris did, just C&P on to my car

[MadMatt]

Variante I am not that surprised. As I wrote in your thread with so much front downforce you'll have issues with balancing the rear as getting clean air can be a struggle.

It might also be something else such as a meshing issue but julien refined it a lot since the early steps so I doubt that's the reason.

[crxdave]

From the first race: I've got a diffuser that is being seriously reduced in performance by rear wheel outwash, a rear wing that stalls in the centre & not a lot of front downforce!

But hey, it's a learning curve & I'm already working on some ideas to try and improve.

[variante]

Matt, the car had the CoP located at 1.63m in my "private tests": perfectly balaced. From the official results, tha actual CoP is not dramatically out of target...If the RW had worked fine, i would still have the right CoP.

To understand the simulations discrepancy on the RW i'll post some images later on.