SimScale CAE Forum

German Workshop Session 3


#1

Hello,
I got a problem with the german workshop session 3, its about to select faces and add them to the mesh operation.
Picture 5 and 6 show the sequence, topic link and sim link. In the exercise they used the old workbench, there was a button to add the selection. I can find it now, is it no longer possible ?

Regards
Kai


#2

Hi Kai!

You can add the refinements (surface, layer etc…) by clicking on the + symbol and then add the selection of the viewer - it is quite different from the old WB. Does that somehow answer your question?

Best,

Jousef


#3

mh, no sorry i didnt found it.

Do i use the right mesh type ? In the tutorial its “Automatic snappy HexMesh for internal flow”, at my project i use the Hex-dominant. Is that maybe wrong ?

Regards
Kai


#4

Hi Kai!

Hex-dominant is fine! If you want to have more parameters to adapt the mesh, the parametric option is the way to go.

Best,

Jousef


#5

Hey @jousefm,
with help from the support, it worked :).

I set up a simulation, but i got strange results.
But first i got a new question about the new workbench.
In the tutorial, you have to change the numerics, like on this the picture.


At the new workbench some textfields are missing.

I change the relaxation type to manual, and got three text fields.
Is my assumption right, that ( P ) on the new workbench ist p_rgh on the old , (U) is U and (T) is h ?
What is with the input for rho, and the solver for p_rgh modified pressure solver ?
Where can i input that ?

ok, now lets go to the results.
This picture is from the workshop.


This are my results.

Same area as the screenshot from the workbench.
And with a free area.

Why i get this strange results ?

And a of topic question, how can i post screenshot which enlagre when you click on it ?

Best regards
Kai


#6

Hi @Kai_himself,

maybe @Get_Barried and @vgon_alves can help you out here.

Cheers,

Jousef


#7

Hi @Kai_himself,

Just got the weekend off and normally I don’t browse the forums till Monday. But this looks interesting so, I’ll get back to you tomorrow.

Do post if you find anything interesting in the mean time!

Cheers Kai.

Regards,
Barry


#8

Hey @Get_Barried,
i started a new try, but it wont work. The GAMG solver for p_rgh iterats 1000 per time step, the progress was really slow.

GAMG: Solving for p_rgh, Initial residual = 0.000851707111775, Final residual = 1.02529662427e-06, No Iterations 1000

I dont find the mistake on the boundary conditions or anything like this.

How i do properly set up the numerics right?
I have to do 5 changes in the numerics like in the workshop.


At the workbench 2, i change the Relaxation type to Manuel, now i can enter three values.

I suppose, that
(P) Modified pressure field is Relaxation factor for field p_rgh ?
(U) Velocity equation is Relaxation factor for equation U ?
What is about (T), h and rho, i dont find a line to enter these values.
Are these values no more necessary in the workbench 2 ?

Best regards
Kai


#9

Hi @Kai_himself,

Apologies for not replying as I said I would. Was really caught up with work and this completely flew over my head.

Hmm yes I noticed a few things that are not so clear or available for tuning anymore in the numerics. I think they will have to re-work it. Following the tutorial might not be possible or the best solution. Could we work on getting the results out and comparing the results against that from the workshop? That might be a better solution till the workshop is updated.

@jousefm Is there any documentation for changes to the workshop over to the new workbench? I don’t think its updated nor does the team have time. Maybe you could notify some people and get them to at least document the changes?


#10

Hey @Get_Barried,
no problem :).
Ok, i try to complet the simulation and compare the results, i will get back to you.

Best regards and a nice weekend
Kai


#11

Hi Barry & Kai and sorry for the delay.

Indeed there are only some resources available but our application engineers are currently working on new material so stay tuned :slight_smile:

Best,

Jousef