[MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

[CAEdevice]

Before the season started, I was working on a certificate for last years champ, Variante. I still have not finished it. The idea is for you guys to have something to show future employers, as winning this championship definitely proves great skills as aerodynamisist.

Variante already has a super cool and trendy certificate on the Blockchain, that will last forever. It signed by CAEdevice, in the future it would be great if the certificate were signed by the MVRC staff.

https://bitscribble.com/?search=Team%20Variante

For the coming race then, I will keep the current and the potential new CoP calculation in MFlow and you guys will get to use the one in your advantage. For the following race, I will then hopefully figure out which one is correct.

Sorry to bother you, but does "keep the current" mean release 201909?

[LVDH]

OK, I have news, the CoP calculation is indeed wrong in MVRC. I checked it many times the last days, today I started everything from scratch and found the mistake. If I have time, I will illustrate it later. Right now I will create a new version of MFlow. It will export two CoPs and you guys will get to use the one in your favor. I will have to talk to Richard about how to handle the first race. I assume, some results will get updated as people who did correct math should not get punished.

[LVDH]

OK,
shame over me. I have finally found the well hidden mistake in the CoP calculation. It is now fixed in the newest MFlow version. I uploaded a bit too fast, now it does not carry a new name as it should.
Now you will find two total values in the report. You can take the one you like more. I hope you have noticed that MFlow creates this one line, which you can copy-paste into the Virtual Stop Watch. This one uses the better CoP and contains the KVRC/MVRC CoP-correction (5cm in you advantage). For race three only the new and correct calculation will be used.
I will discuss with Richard if we delay race 2 a few days and what we will do with race one. I have already entered the new numbers into a sheet and it changes surprisingly little, I think only one person will be very happy.
If we ever organize an MVRC meeting, I think I have already promised to spend a few beers, so this mistake means you can all punch me really hard in my stomach, it was a bad one.

[Ft5fTL]

I still don't understand the positive lift on the front end. My last simulation about that car had a result like this:

"Cd: 1.2087631888, Cl: -1.7033494776, Cl/Cd: -1.4091672326, Cl(f): -0.7655662530, Cl(r): -0.9377832245, CoP: 1.872"

[LVDH]

This here is perfectly fine. Cl(f) is the front downforce coefficient and Cl(r) the one for the rear. As both are negative, both indicate downforce, so this is what you want to have.

[machin]

I still don't understand the positive lift on the front end. My last simulation about that car had a result like this:

"Cd: 1.2087631888, Cl: -1.7033494776, Cl/Cd: -1.4091672326, Cl(f): -0.7655662530, Cl(r): -0.9377832245, CoP: 1.872"

Preliminary reports from spotters at the track suggest that your car has improved quite a bit with the new version of MantiumFlow... we should have an update tonight....

[LVDH]

So, I have submitted the new numbers to Richard, he will create a new video. To relieve some of the tension, the winner stays the same and the back-markers as well. In the mid-field where the teams are closer together, there are some changes in position.
After Richard releases the video, I will show the table with all the new data, so you can see what exactly changed.

Also we have decided to delay the next submission deadline until next Tuesday, so you have two additional days.

[Ft5fTL]

Code: Select all

lRef        3.4;

to

Code: Select all

lRef        1.0;

Then you can run the case.

Are you sure about that? I'm getting better balanced results at 3.4.

[LVDH]

Well in the end both approaches are wrong as long as you are not using the latest MFlow version, which was uploaded only yesterday in case you missed it. The new one will export the correct value for you. As transition though, it also calculates with the old wrong method and lets you use the one in your advantage. As soon as the next race is over only the new definitely correct one will be used.

[machin]

Ok... let's do this... again....

[CAEdevice]

... and again... thanks!

I noticed that the laptime of the Ferrari is about the same of the winner... cool detail

[rjsa]

Still better than I hoped.

We’ re getting new reports? Or a table?

[machin]

The only change is the COP calculation, so you only need that new figure; the rest of the report should still all be valid. Andre will update the table.

[LVDH]

Here is the new table:

If you want, I can send out a new report. You could just as well open the html of the report with a text editor and change the numbers.
Saturday or Sunday morning, I will try to update the challenge page so it will show these kind of tables in a nice format. It might be advisable to copy-paste the rules, in case the page will be inaccessible at the very moment you want to read them.
And for those who missed it, we have delayed the next submission deadline by two days.

And for those who think that with the new CoP calculation all CoP related matters are solved: Please have a look at the Cm plot from the Idadox car:

With the new calculation, only the numbers change but not the shape of the curve. If you only run for 2500 iterations and the curve has not flattened out yet, you have to run longer. If not, you are relaying on inaccurate information. Please keep this in mind.

[rjsa]

Hi Andre, I ‘ll repeat the car with the RW pillars anyway, I’ll only get home on Wednesday.