SimScale CAE Forum

CFD School Project


#1

My name is Alejandro and I am a 17 year old student who is currntly trying to finish a high school project.
I have got a very simple prototipe to analyze, but I do not know which values I need to put. As the results were not coming, I tried to copy a couple of projects but I do not know why my results are different from the model.
If someone could help me it would be much appreaciated,

Thank you

Alejandro

LINK frontwing: https://www.simscale.com/projects/acogollo/air_flow_around_a_frontwing/

LINK basic car: https://www.simscale.com/projects/acogollo/tr_1-0/


#2

Hi Alejandro - great to see young people using simulation for their school projects! :slight_smile:

Let us dissect each project and I will give you some tips on where you should work on.


  1. For the frontwing I can definitely tell you that the mesh is too coarse and you should increase the fineness of the mesh and make sure that the boundary conditions are set correctly.

Use this tutorial for your wing: Front Wing - CFD Analysis


  1. For the car itself the domain is way too small and the boundary conditions to not match as well. Also make sure that you use velocity inlet and pressure outlet and not the same type like velocity - velocity and pressure - pressure which has numerical reasons.

Please have a look at the following project and use it as a template: Full Car Aerodynamics


Let me know if you have any further questions. If so, please either tag me or one of our PowerUsers @Get_Barried, @vgon_alves or @pfernandez.


Best,

Jousef


#3

Thank you so much,
I tried to open the Front Wing - CFD Analysis but it says I do not have access to that.
Also I am having problems with the region refinements because I do not know what values go there, I have tried to copy the other project but it seems my version of Sim Scale is different.
Also I do not how to increase the fineness of the mesh.


#4

Hi Alejandro,

should work now! Indeed I should have mentioned that the interface changed from the old workbench to the modern workbench 2.0 which is quite different from the old one but the naming is basically identical. The fineness of the mesh can be adapted with the so called “levels” that you can find inside the mesher but also other parameters.

If you are curious about the SnappyHexMesh (SHM) settings have a look at the documentation or at this document which easily explains the concept of SHM: https://openfoamwiki.net/images/f/f0/Final-AndrewJacksonSlidesOFW7.pdf - I also do not know what every parameter does and have to look up things from time to time :wink:


If you have specific problems just ask here and we will try to help you out!

Cheers,

Jousef


#5

Thabk you so much,
I have watched it, and I have managed to do it again and get better results, and now I am on my way to paraview post processing


#6

I have used paraview to analyze the post process results, but I think something is wrong with my simulation because I am not able to see diferences on the pressure and no flow lines are available


#7

Hi @acogollo!

Which project are you referring to? Will have a look at it. Also note that downloading data when you do not see results in the online post-processor does not make much sense and is basically wasted time. A good thing to do is to check it on our platform first and - if you want to do more sophisticated post-processing analysis - then download the results (if it’s that what you did).

Cheers,

Jousef


#8

hello thank you very much for your answers! I am very sorry to have to be continually contacting you. and I thank you very much for your kindness.

The project that I was referring to was the frontwing, I have obtained results that I then passed to Paraview but I think something is not quite right because I do not get the different colors and flow lines.

I am doing a class work that I will present after Christmas, I am worried because I thought I could have results more easily, maybe I have risked a lot because I did not have knowledge of these programs until now nor I knew how to work with graphic design and first I tried to learn to work with fusion 360 then I’ve worked with SimScale and now with Paraview. It really is complicated without having previous experience and without having too much time to do all the tests and I am dedicating the Christmas holidays to be able to complete it but I do not have too much time left and I am worried.
My initial idea was to design a basic form (TR 1.0) and a F1 type car (even if it was basic) to do the CFD and compare results.
But working with the “frontwing” (I copied it) I have not managed to see the pressures and the flow lines, so I do not know how I will manage to do the rest, at least if I do not have time I would try to present the work on the frontwing.

I hope you forgive me for so many questions and problems that I consult you.
Thank you.


#9

Hi Alejandro,

as far as I can see your frontwing model is still in the old state and requires a much finer mesh. Just use the template/tutorial I posted above and you will get the results you are looking for. If you are confused because of the old workbench interface simply have a look at old projects like this one right here: F1 - Front Wing Studies.

When do you have to hand in your project? Let me know if you need assistance with it.

Best,

Jousef