Page 14 of 91
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 02 Sep 2016, 19:00
by LVDH
I hope at some point I will get the slide show function working on the homepage. I have so many cool renders from you guys but right now only one image per team.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 09:30
by CAEdevice
After submitting the car for the first race, I dedicate some time to think about the rules (LDVH would say "to read the rule book for the first time" and he would not be completely wrong).
I think that the rule K4.1 is too restricrive: since we have a very good and realistic model of the radiators, thanks to OpenFoam and MantiumWFlow, the only rules should be the required flow, the radiator angle (in order to simplify the use of porous media) and the radiator vertical position (we do not simulate the real wheigt distribution, someone could think to place radiators over the engine). I think that the minimum surface areas only makes things more complicated.
Also the 1200mm rule is not useful woth the present rule. I think that a design like the one in the oicture would not be allowed, since the iutlets are not 1200mm far from the inlets:
The inlet minimum area (50000mm2) makes them too big to be placed in front of the car (or in position where the receive a direct 44.7m/s flow), so the must be placed in low pressure areas and... they become bigger
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 09:43
by LVDH
You are right some rules are still a bit too restrictive for the new setup.
They all stayed for certain reasons. Mainly to ensure a smooth transition from the old championship. You guys were more or less able to use the car you wanted to race anyways. There was no pressure for a complete redesign.
Depending on how much time Chris and I have we will lift some of these restrictions for the low downforce races.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 11:31
by CAEdevice
I felt the pressure for a complete redesign when I saw the first numbers from the simulation of my old KVRC car (opt1) ... I am curious to see the cars and their performance.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 13:32
by etsmc
CAEdevice wrote:After submitting the car for the first race, I dedicate some time to think about the rules (LDVH would say "to read the rule book for the first time" and he would not be completely wrong).
I think that the rule K4.1 is too restricrive: since we have a very good and realistic model of the radiators, thanks to OpenFoam and MantiumWFlow, the only rules should be the required flow, the radiator angle (in order to simplify the use of porous media) and the radiator vertical position (we do not simulate the real wheigt distribution, someone could think to place radiators over the engine). I think that the minimum surface areas only makes things more complicated.
Also the 1200mm rule is not useful woth the present rule. I think that a design like the one in the oicture would not be allowed, since the iutlets are not 1200mm far from the inlets:
http://www.mulsannescorner.com/Lola-MS1.jpg
The inlet minimum area (50000mm2) makes them too big to be placed in front of the car (or in position where the receive a direct 44.7m/s flow), so the must be placed in low pressure areas and... they become bigger
Both of the concepts of radiator in the front and over the engine are possible. .
I am interested to see how my front cooling concept goes with the new porous heat exchanger but wont be able to do that till i can run a test myself or race 2.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 13:40
by CAEdevice
Ok, I was not clear enough.
The radiator in front of the car is possible but the minimum inlet surface area would be over dimensioned.
The radiator over the engine is probably a very good solution (I am considering to use it in next races), but in a real car it would move the center of mass too high.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 13:52
by cdsavage
There's about 36 hours until the deadline for the first MVRC round. Hopefully everyone has had a good check of the rulebook before submitting, because unlike with KVRC, there won't be a resubmission process. While I would urge everyone to read through the full rulebook, here are a few quick checks to do first:
- you've included all of the parts specified in K1.4, since this has changed completely compared to KVRC
- the size of the STL files, before they're compressed, is under the size limit
- are the inlet and exhaust surfaces are completely flat, planar shapes?
- when all of the parts are imported together into the same scene (for example, using Paraview), they need to be positioned correctly relative to each other, and with a scale of 1 unit = 1m
- when the bodywork volume, rear wing volume and visibility volume are then imported into the same scene 'on top' of those parts, there are no parts of the car that are visible, it sits completely inside those volumes (using a different colour for the modeled parts and the volumes makes this easy to check)
- if the visibility volume is then deleted, are there any parts made visible other than the surfaces of the cockpit plus the mirrors?
- if the rear wing volume is deleted, are there any parts made visible other than the rear wing and the attachments?
- Does the bodywork completely enclose the footbox template, cockpit template, engine template and gearbox template? (again, using a different colour makes this easy to see)
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 16:39
by LVDH
One more thing I would like to add:
Please use meaningful file names. I suggest Teamname_Monaco_VersionNumber.zip.
And the *.zip is actually important in case you are not using the Dropbox submission.
Somehow the file uploader on the homepage only accepts a few formats, one of them is zip and tar.gz is not.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 18:11
by CAEdevice
In case I had a new idea tonight: would it be possible to replace the submission (before the deadline) with an update, as we did last year?
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 18:30
by LVDH
Yes, of coarse, go ahead
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 18:34
by CAEdevice
LVDH wrote:Yes, of coarse, go ahead
I promised myself to not think about anything related to CAD/CAE/CFD during the weekend... but my mind is still trying to improve that embarassing downforce.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 19:21
by TalnoRacing
I would like to please ask for help again.
I am able to successfully run a simulation without any errors showing. However, in the "solver" file generated in the working directory, I have a "0" value for the Cm, Cd, Cl, Cl(f) and Cl(r) values. I also do not know which file to open in Paraview to view the results.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 19:30
by CAEdevice
Are your zeros "exact" or "near to zero" (10^-5 or less?). Did you pit the files in the right directory and with right placement? Are the directory names correct?
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 19:35
by TalnoRacing
Yes I checked again. This is the result in the solver file:
Coefficients
Cm : 0 (pressure: 0 viscous: 0)
Cd : 0 (pressure: 0 viscous: 0)
Cl : 0 (pressure: 0 viscous: 0)
Cl(f) : 0
Cl(r) : 0
I get this for each time interval.
Re: [MVRC] Mantium Virtual Racecar Challenge 2016
Posted: 03 Sep 2016, 19:40
by CAEdevice
What about the numbers in the files of the "post processing" directory?