F1technical.net

Can you retroactively use your 2-day extension?

If so, depending on the results (should be done in around 7-8h), I might change my submission to the current iteration, since the current submission seems to have mesh and intake issues .

BlakjeKaas wrote: ↑

18 Sep 2018, 14:30

Can you retroactively use your 2-day extension?

If so, depending on the results (should be done in around 7-8h), I might change my submission to the current iteration, since the current submission seems to have mesh and intake issues .

For an answer to this you can check the rules.
It would be helpful if you guys could use the footer in this forum if your name does not match your team name. At least today, I figured out what your avatar spells. I have cleaned and fixed all cars and the simulations are running, so in addition to the answer in the rules you get another "no" to your question. Sorry about this.

I guess most of you are aware of Mussane's Corner, which is a great page if you like images of cool cars. Recently I bumped into another similar one, which might be new to some of you as well:
http://www.gurneyflap.com/index.html
The page seems to be a bit old but the images are very cool. What do you guys think about these devices:

Many cars seem to have them.

That's pretty much what I figured, especially since the cars are already posted on the website.

Luckily a clean mesh seems to solve a great part of the problems.

Interesting website, when I've got a general concept working for the car I'm definitely going to check it out for all those intricate details.

Hi, I had some question and little feedback on MantiumFlow. First, I used the new version a few times and I noticed that in the new added line (so, only in this line), which you can copy to virtual stopwatch, the cop not always show the correct values and the cooling flow is always 6.
Also I had some questions. First, can I find somewhere how Cl and Cd and Cp are calculated? Like which length scales are used for example.
Secondly, what am I exactly seeing in the new added graphs? Seems like a kind of vortexes? And what is exactly the differeces between Cp total and Cp slice?
Third, the last simulations i use, next to the MantiumFlow postprocessor, the graphs I can make with Paraview, which are really cool! With paraview it is possible to slice your car anywhere you like. Is it also possible to do this with the analyses you got from MantiumFlow postprocessor (but than by yourself ofcourse)? Like the Cp slices or streamlines on any distance you like? I guess MantiumFlow is building a case and this is solved by BlueCFD. Is that correct? So, to have a better understanding about what is going on, just start learning to work with BlueCFD? Or is MantiumFlow doing more?

BlueCFD is a windows porting of OpenFoam, the solver (I think OF5). There are some alternatives, including the Ubuntu bash under Win10, but BlueCFD is a very good porting.

MantiumFlow is a pre/post processor, one of a kind for simplicity, it does a different job.

I am not very experienced with CFD, I only did some small jobs with Simflow e Helyx-OS, other partecipants as JJR, and LDVH as well, can say you much more.

Team_Bart wrote: ↑

18 Sep 2018, 22:18

Hi, I had some question and little feedback on MantiumFlow.

This is great, I like feedback of all kinds very much. Somehow customers do not give any feedback even when I ask, no idea why.

Team_Bart wrote: ↑

18 Sep 2018, 22:18

First, I used the new version a few times and I noticed that in the new added line (so, only in this line), which you can copy to virtual stopwatch, the cop not always show the correct values and the cooling flow is always 6.

So you are a bit new to this to know. The corrected CoP thing is old carry over from the days this championship was called "KVRC". Your CoP gets corrected up to 5cm to your advantage. I hope this is what you see. If I made a mistake here, please send the case.
The cooling flow here only gets set to 6 if it is not automatically detected which of the monitored values is the cooling flow. When this happens there should be an additional message. I will check later if it does not find its way into the HTML report. It is for sure in the text output in the command window.

Team_Bart wrote: ↑

18 Sep 2018, 22:18

Also I had some questions. First, can I find somewhere how Cl and Cd and Cp are calculated? Like which length scales are used for example.

I guess as you are a student you can do some research yourself. In the case folder, use a text editor to check the file system/forceCoeffs. You will learn a bit about OpenFOAM and that it can be a bit confusing.

Team_Bart wrote: ↑

18 Sep 2018, 22:18

Secondly, what am I exactly seeing in the new added graphs? Seems like a kind of vortexes?

Yes, by showing isosurfaces of certain Lambda2 values, it is possible to visualize vortex structures. Here these vortices are also colored with the velocity which gives some additional information. This Lambda2 stuff is not very intuitive in my opinion. You can check how it is calculated here:
https://en.wikipedia.org/wiki/Lambda2_method

Team_Bart wrote: ↑

18 Sep 2018, 22:18

And what is exactly the differeces between Cp total and Cp slice?

As you are a student, you should figure this out on your own and learn. This should be of some help:
https://en.wikipedia.org/wiki/Bernoulli%27s_principle

Team_Bart wrote: ↑

18 Sep 2018, 22:18

Third, the last simulations i use, next to the MantiumFlow postprocessor, the graphs I can make with Paraview, which are really cool! With paraview it is possible to slice your car anywhere you like. Is it also possible to do this with the analyses you got from MantiumFlow postprocessor (but than by yourself ofcourse)? Like the Cp slices or streamlines on any distance you like?

The idea of MantiumFlow is to automate the whole process. Before building the simulation you can go into the settings and change the number of slices. Additional streamlines are generated on all monitoring surfaces. So you can add more than just the one in your radiator. The idea behind all this is to make CFD accessible to non-CFD engineers. But as you will have noticed, you can just open the case with Paraview and do whatever you want with it.

Team_Bart wrote: ↑

18 Sep 2018, 22:18

I guess MantiumFlow is building a case and this is solved by BlueCFD. Is that correct? So, to have a better understanding about what is going on, just start learning to work with BlueCFD? Or is MantiumFlow doing more?

MantiumFlow is a pre and post-processer, in this case for OpenFOAM. This means it helps create the case for OpenFOAM and later post-processes it, which includes generating that html report you get in the end.
OpenFOAM is the actual CFD software we are using. CFD solvers usually run on Linux (most software is super expensive and tied to the number of CPU cores you want to use, so performance is very important).
For Windows, the way to run OpenFOAM is the version by BlueCFD. This makes running OF on Windows very easy and convenient.

Thanks for the answers!

I would like to ask for help with MantiumFlow. I finally managed to get the GUI working for MantiumFlow on Windows, but now I get the following error type when tying to run the case:

”.runCase.sh: line xx (18 sequential numbers): surfaceTransformPoints: command not found”

the error then changes to:

”.runCase.sh: line xx (one number): blockMesh: command not found”

then changes to:

”.runCase.sh: line xx (one number): decomposePar: command not found”

then changes to many lines as follows:

”.runCase.sh: line xx (18 sequential numbers): mpirun: command not found”

I even tried running the "runCase.sh" file through the Windows command window, but it does nothing.

looks like BlueCFD isnt installed properly...or at least that is what it looks like to me.

Hi guys,
I was incredibly busy and did not have time to look into this yet (It looks like we will see the Sepang results this Sunday). Does anyone have a good idea how to perform a simple check to see if the blueCFD installation is working?
Thanks.

Looks like Andre is not pulling out the promised car reviews ( ), so here is a teaser of a small tech article I will publish tomorrow (hopefully) about my car. I think I will open a dedicated page, as we used to do in the good old days.

variante wrote: ↑

22 Sep 2018, 15:31

Looks like Andre is not pulling out the promised car reviews ( ), so here is a teaser of a small tech article I will publish tomorrow (hopefully) about my car. I think I will open a dedicated page, as we used to do in the good old days.

https://i.imgur.com/ETysJ3l.jpg

Thanks! I don't have any news about my car. After spending 1 month testing a wrong development direction, I am going back to the car I used in the first race. I will surely try to copy Variante's diffuser, I don't think it will give more efficiency, but with my layout it should improve cooling.

Well, the cars have all been out for practice runs around the Sepang circuit... and it is looking very tight! One front runner is complaining about a touch of understeer...

A backmarker, however, is complaining about oversteer.

variante wrote: ↑

22 Sep 2018, 15:31

Looks like Andre is not pulling out the promised car reviews ( ), so here is a teaser of a small tech article I will publish tomorrow (hopefully) about my car. I think I will open a dedicated page, as we used to do in the good old days.

https://i.imgur.com/ETysJ3l.jpg

I cannot wait to see this. My idea to to show some interesting aspects of the top three cars when I have time next week.
Also MVRC is still waiting for a CFD journalist to cover the championship. Please apply.

Last Friday, I was so happy to end the week, that I forgot to mention that the scrutineering results are out:
https://mantiumchallenge.com/scrutineer ... pang-2018/

Monday I will finally be able to look into the Talno issue myself, if nobody else can help him today.


Some three hours to go and we will see what happened in Sepang...