[MVRC] CCE GP001

Post here information about your own engineering projects, including but not limited to building your own car or designing a virtual car through CAD.
User avatar
LVDH
30
Joined: Tue Mar 31, 2015 1:23 pm

Re: [MVRC] CCE GP001

Post

Koldskaal wrote:
Mon Mar 30, 2020 1:16 pm
LIC! Line integral convolution everywhere! I think everyone should be looking at LIC slices.
I absolutely agree. This is what I hate the most about my software. Actually in the very first versions, it was included in the post-processing. At that time it was done in Paraview. I had to change that though and moved on to VTK. I have sat down many times to add SLIC into the VTK post-processing and failed every time. If you or someone else can get it done, I will be more than just grateful not only because a warm handshake is currently a frowned upon thing.

User avatar
machin
187
Joined: Tue Nov 25, 2008 1:45 pm

Re: [MVRC] CCE GP001

Post

Koldskaal wrote:
Mon Mar 30, 2020 1:16 pm
I think what we are seeing is a conflict of interest :D . I want to share my thoughts partly to give people a nudge in the right direction. Partly so that more knowledgeable people will correct me when I am wrong about something. But there are two reasons why I am holding back slightly:
1. I don’t think anyone wants the solutions to be “formulaic”. We all want to see creative solutions to these problems.
2. The obvious one, I want to win. I am going to keep some ideas private.
Fair points, :-), although I don't think "Try and be more (or less) aggressive here" is really going to lead to every design becoming "formulaic".. indeed I think this sort of advice isn't really going to threaten your end of the grid anyway.... :P
COMPETITION CAR ENGINEERING -Home of VIRTUAL STOPWATCH

User avatar
machin
187
Joined: Tue Nov 25, 2008 1:45 pm

Re: [MVRC] CCE GP001

Post

Well, we now have one year of updates to the CCE GP001 (That's still only 5 updates in total)… unfortunately a few of those were "wasted" chasing sufficient cooling flow, but I feel that I now have a decent-ish front wing, so I have some pretty good images showing a "bad" design and a "good-ish" design:

So the upper images show the first front wing, which was really just "thrown together" with no other thought than it looked sort of "wing like". The lower wing is the latest version with 3 elements and designed in accordance with the "Variante Circle Method":-

Image

The original wing has two clear issues: the upper element shows no positive pressure on the upper surface; this is clearly showing that the AoA /camber of that element is too low in comparison to the oncoming flow, conversely the lower surface of both elements are experiencing separation as evidenced by the loss of Cp_tot in a big plume emanating from the lower surface, most likely due to the lower element being at too high an AoA / or the profile too cambered, and since this wing only has two elements it means that there is insufficient injection of "fresh" air from the upper surface, so the wing just stalls badly.

The latest wing solves these problems: a gentle progression of AoA across the elements, a consistant profile camber and injection of fresh air at appropriate points (now two points, due to the three elements), and the result is positive pressure on the upper face of all elements and very little loss of Cp_tot….

The plan (/hope :oops: ) for the next race is to get the rear wing to the same level of performance....
COMPETITION CAR ENGINEERING -Home of VIRTUAL STOPWATCH

User avatar
variante
103
Joined: Mon Apr 09, 2012 10:36 am
Location: Monza

Re: [MVRC] CCE GP001

Post

machin wrote:
Wed Jun 10, 2020 9:27 pm
The lower wing is the latest version with 3 elements and designed in accordance with the "Variante Circle Method":-
Hahah nice to hear that it worked! Yeah, it looks like a very nice airfoil now.
The next step is the "Ellipse Method", if you feel brave enough. When properly executed, it should give you a more aggressive airfoil and thus allow you to shorten the wing (for the same total DF) and let more air pass towards the floor, radiators, rear wing,...

The drawback, which seemengly you've already experienced, is that the tyre wake becomes quite significant...

Anyway, some horizonal planes around the bargeboard area should further help the rear ring, and they should be easy to make.

User avatar
machin
187
Joined: Tue Nov 25, 2008 1:45 pm

Re: [MVRC] CCE GP001

Post

variante wrote:
Wed Jun 10, 2020 10:17 pm
Anyway, some horizonal planes around the bargeboard area should further help the rear ring, and they should be easy to make.
Yes, I think I must have read your mind :wink: ; I've made the updates to the car already: New Front Wing end plates, new barge boards and new rear wing. There's a hundred other things I could optimise, but as I'm not doing my own CFD I can only rely on the official tests, so I don't want to change too much at once...or I won't know what worked...
COMPETITION CAR ENGINEERING -Home of VIRTUAL STOPWATCH

User avatar
machin
187
Joined: Tue Nov 25, 2008 1:45 pm

Re: [MVRC] CCE GP001

Post

So race 2 was a bit of a disaster.... The thought process was to try and improve the efficiency of the rear wing... In itself that goal was achieved quite nicely; a 42% increase in efficiency was achieved... however the reduction of downforce, and the reduction of drag, resulted in a huge forward shift in the COP, and therefore the wooden spoon award of slowest car through the corners :oops:

I also tried out a new design of barge boards, but their effect on downforce wasn't particularly noticeable, possibly this was masked by the lack of diffuser : rear-wing interaction....

On the positive side Andre (@Mantium Flow) kindly ran the CFD of my car at both 0 degrees and 1 degree of rake. The little animation below shows how this affects the lower surface pressure distribution...
Image

The overall drag and downforce levels barely changed between the two rake angles, but the COP shifted quite considerably, which you can see see by the changing colour in the diffuser throat and tea tray. So a rather useful tuning device in the quest for better COP in future races.
COMPETITION CAR ENGINEERING -Home of VIRTUAL STOPWATCH

k.ko100v
k.ko100v
14
Joined: Fri Aug 31, 2012 5:58 am

Re: [MVRC] CCE GP001

Post

machin wrote:
Wed Jul 15, 2020 9:10 pm
So race 2 was a bit of a disaster.... The thought process was to try and improve the efficiency of the rear wing... In itself that goal was achieved quite nicely; a 42% increase in efficiency was achieved... however the reduction of downforce, and the reduction of drag, resulted in a huge forward shift in the COP, and therefore the wooden spoon award of slowest car through the corners :oops:

I also tried out a new design of barge boards, but their effect on downforce wasn't particularly noticeable, possibly this was masked by the lack of diffuser : rear-wing interaction....

On the positive side Andre (@Mantium Flow) kindly ran the CFD of my car at both 0 degrees and 1 degree of rake. The little animation below shows how this affects the lower surface pressure distribution...
/gif/f1-cfd-OdXBpz

The overall drag and downforce levels barely changed between the two rake angles, but the COP shifted quite considerably, which you can see see by the changing colour in the diffuser throat and tea tray. So a rather useful tuning device in the quest for better COP in future races.
Is there any instruction how I can set up the rake. I try several times to set the "pitch" value to -1, but it didn't work.

User avatar
LVDH
30
Joined: Tue Mar 31, 2015 1:23 pm

Re: [MVRC] CCE GP001

Post

You just have to set it to -1 in the settings and hit apply. It does not affect the parts shown in the GUI. The transformation only happens in OF. To be sure about the setting getting applied, you can check the runCase.sh file after building the case with MantiumFlow.

k.ko100v
k.ko100v
14
Joined: Fri Aug 31, 2012 5:58 am

Re: [MVRC] CCE GP001

Post

LVDH wrote:
Tue Aug 18, 2020 4:31 pm
You just have to set it to -1 in the settings and hit apply. It does not affect the parts shown in the GUI. The transformation only happens in OF. To be sure about the setting getting applied, you can check the runCase.sh file after building the case with MantiumFlow.
Thanks, just found that there is "apply" button #-o

Cheers,
Krasen