[MVRC] Mantium Virtual Racecar Challenge 2016

[CAEdevice]

Thanks, it's ok to not change anything (despite I think that a small minimum heat exchanger area would be better, to balance the impossibility to rotate it): the important thing is to know it in advance.

For next year, there are some things that I hope will be implemented:

1) 2nd order scheme
2) Slightly better mesh (I don't mean more layers, but a more accurate snapping)
3) Possibility to use heavier (more accurate) stls
4) Rotated heat exchangers (not "rotating"). It would be enough to have a discrete number of orientations: normal to the flow, 30° with respect to the ground OR to the simmetry plane. This would make the coding a bit easier.
5) Brake cooling ducts

[Ft5fTL]

Well everything is created from scratch about cooling, and it didnt run any problems on wflow so it should be fine this time. Thanks for the kind words.

[AratzH]

I would post this earlier but i didnt had internet connection for a week. I uploaded my car through my phone before the monthly quota kicked in so i dont know if the staff even received the car. Let me know if there is a problem about that.

So this is the improved low drag spec car that raced at sepang. I changed almost every aspect of the car to get a better result this time. There is a brand new cooling that gives some great numbers. But that design leaded to some legal issues about footbox since the cooling has ducts that i carved on the front of the car. Re-desinged the front diffuser and re-introduced the front wheel pod diffuser (dunno if this is the name of it) for gaining what i did lost when i lowered the diffuser for the footbox issues. Changed the rear wing to single element for lowering the drag.
https://snag.gy/Rp14Wd.jpg

The only concern that i have is that i only could test the car on mvrc_fast option on wflow. Couldnt get it work on the standart test parameters, gived the error that i posted on the mvrc forum (errors like this : Cannot find any patch or group names matching “wing_front.*).

I just went to your blog and I must say, your car looks really nice. At first it remained me of the Toyota TS020 but I can now definitively see the BMW inspiration. I have myself modeled and CFD'd various le mans prototypes and there is a lot to learn about. As you mention in your post, it is incredible how much air the diffuser can draw from the sides of the car. Now that I lost my "surprise factor" in Sepang, I can show some more interesting pictures:


I made minor changes, first and foremost to be legal. Little tweaking of the heat exchanger´s intake and exhaust ducts (now my MFlow calculations show 3.4 m3/s hopefully it will be enough). This unintentionally increased my front downforce by an unexpected amount, so I made some more tweaking to the rear diffuser to compensate. I am finally out of my target for Df and Dr, but my L/D is spot on. Even better, according to the lap time sim, my config is a little faster than my target.



Hopefully I won´t forget some minor rule detail this time and maybe get my first victory!

Regarding Mateo´s comments, I completely agree. Specially with heat exchanger orientation and brake duct modeling. The more things the more interesting. One thing that I would love to add (but I understand that it would make the rule checking process a nightmare) would be allowing to move the parts of the car around withing some fixed volume. This would allow for other interesting designs like front engined etc.

[CAEdevice]

Hi Aratz, your car is astonishing for both general concept and details. I am quite sure (from your words about efficiency) that it is faster than mine: you can aim to the victory.

On the contrary, I am at an impasse point, I hope to have new ideas for Le Mans.

[CAEdevice]

About your interesting idea to move the parts: we would need to roughly estimate the center of mass changes (ex. When moving the engine position). With Solidworks and other serious CAD (btw: your CAD model quality is very good) it would be quite easy to automatically compute it (ex. working in assembly mode). Editing the mechanical parts position could be optional, so who is using sketchup could simply mantain the provided parts as they are in the template.

[Ft5fTL]

I got the inspiration from the BMW but i can see the similarities with the Toyota. Actually its more similar to Toyota than BMW. Your car does get more sideflow to the diffuser than mine atm.

We can supply a text file about the parts that we moved, still that will slow down the checking but i dont think it would turn to nightmare. Maybe along with the rear engined car template pack, we can have a second template pack for a front engined car. I always wanted to do a front engined consept.

[CAEdevice]

I agree with your proposal.

Alternatively a second template (front engined) could be provided. I like front engined too!

[CAEdevice]

I tried to improve the first resubmission, but the gain of efficiency was so small (0.02) that I did not resubmit the car.

Has my car already arrived in Sao Paulo?

[TalnoRacing]

My car is submitted, I hope it is in time. Engine cooling remains a problem, running out of ideas to get to 100% power....

[RicME85]

I won't be entering.
Having engine issues. Using Matteo's car I'm getting 40% power (with no modifications). All I have done is created the heat exchanger monitoring surface. Can only assume it's a Sketchup STL issue producing poor results like Andre showed on his site where faces can have an impact on how flow works through the HX.

[CAEdevice]

I won't be entering.
Having engine issues. Using Matteo's car I'm getting 40% power (with no modifications). All I have done is created the heat exchanger monitoring surface. Can only assume it's a Sketchup STL issue producing poor results like Andre showed on his site where faces can have an impact on how flow works through the HX.

If you want, you can send me the car and (knowing how that ducts work, since they are the same I used for the first race) I can help you looking for the issue.

I can provide a more complete car if you prefere. I noticed that the cooling flow dependends on the whole car, roughly:

70% energy of the entering flow (sum of kinetic and pressure energy)

10% internal duct geometry (recirculation can reduce the flow)

20% exit position (it helps if the duct ends in a low pressure area: below the rear wing or below the rear suspension cover if adequately shaped to generate low pressure).

Only point two is defined in the custom car...

Consider that into the ducts of the custom car there is a 100mm thick extruded segment, that helps the design of the heat exchanger (just fill that area and extrude): even with SketchUp it is quite easy to obtain an accurate geometry of the heat exchanger. The similation error caused by bad triangulation should not be greater than 10% in this case.

[Alonso Fan]

Well that's 9th place confirmed for me then.

Submitted late yesterday, changes to the front wing and rear wing, should hopefully get me near the correct cop value. Engine power should remain the same as I've not got round to changing the cooling. Perhaps I'll do it for next season instead of rushing it. I should also have MVRC set up by then.

[LVDH]

OK guys,
the simulations are running and you can have a first look at the cars:

More on the challenge page:
http://mantiumchallenge.com/renders-mvrc-sao-paulo-2016
It seems as if TF had a baby in Italy.

I hope later today I can ship out the newest MantiumWFlow MVRC edition which will contain the post-processing that creates the reports you get after the race.

[CAEdevice]

It looks JJR has submitted two cars I think there is an error with the car n°31.

[CAEdevice]

It looks like JJR worked on the rear diffuser.
Congratulations to mom and dad... Variante's cars is a mix between its previous car body and TF concept, but with front wing winglets and small rear side diffusers inspired by CAEdevice.
If everything works in the new Variante's car, this is, as usual, my virtual podium of the virtual race: 1)Variante 2)TF 3)JJR. In this case I would happy for a 4th o 5th place.