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Marium April 19, 2020 04:34

Importing volume mesh in starccm+
 
Hello all,
I have created a volume mesh in Pointwise and exported the CAE in starccm+ as .ccm.
The issue I am facing is that there's no part and no part to assign in my regions.So when i run it, it shows that-"no parts defined" How to progress further if I import volume mesh in star? I'm working with JBC hull and it will be helpful for me if anyone can suggest a way to simulate imported volume mesh in starcc+

LuckyTran April 19, 2020 04:59

Do you have anything in regions? You don't need parts.

Importing a volume mesh does exactly that, imports a mesh without any parts/CAD data.

Marium April 19, 2020 05:07

1 Attachment(s)
yes, I have assigned boundary condition before importing in star. in this picture, you can see beside the region options they have boundaries. Attachment 76656
I don't know how I can go further with this imported mesh, I can only export .ccm file from pointwise.

LuckyTran April 19, 2020 05:10

Everything is working. You can proceed.

What are you trying to do that you can't?

The mesh is there, it works. Apply your BC's and get on your with simulation and your life.

Marium April 19, 2020 05:21

1 Attachment(s)
The problem is that the tutorial I follow, they worked with parts based automated mesh. So after importing the volume mesh, I proceeded by the instructions when they regions of tank to BC, or other purposes.

So I'm actually quite inept to start. How should I proceed after importing volume mesh? the boundary conditions are applied in the regions and the region needs part(that what error box showedAttachment 76657)

it will be very helpful for me if you can guide me or give me some tutorial link on how to simply work with imported mesh.

LuckyTran April 19, 2020 05:38

Is the picture you provided the tutorial or your case? Please, clearly describe what you have.

If you meshed in a program that is not Star-CCM, when you import it, it will only be a volume mesh and will not have parts attached. That is fine, you do not need parts.

The only caveat is, make sure you click import volume mesh and NOT import CAE model. But that's really hard to mess up, because you cannot import a .ccm file as a CAE model, there will be a different error.

Marium April 19, 2020 05:48

1 Attachment(s)
The picture that I attached is the error I am facing.
ok let me clear my condition. I have imported volume mesh in star from pointwise and now I want to simulate. What should I do next?
like you said to apply BC but when I tried to do, it showed me prompt like this. How I can set new boundary condition here? sorry, I might seem vague but I'm facing difficulty in this section.Attachment 76658

LuckyTran April 19, 2020 05:57

Nothing is wrong with your imported mesh.

Go to continua and create your physics. Click on unspecified in regions and make sure the Physics Continuum is listed there. The Mesh Continuum will normally be NONE, but can end up with something there as well. Leave the parts blank.

In this image, your BC is a type wall. Let's say you wanted to make it a velocity inlet. Well then change the type to velocity inlet. This will open up new nodes in the tree. You'll probably then go to physics values and set it to, i don't know, 2 m/s. Then you're done. Then you click run.

You could just leave it as a wall and click run, then you get flow inside a box.

But really, you'll want to right click boundary-0 and split the surfaces by patch into your inlet/outlet and so on. And then set the BC's.

Marium April 19, 2020 06:22

2 Attachment(s)
thanks for explaining.
I want to create boundary conditions like this. This is from another simulation.Attachment 76659
You said to split the surfaces. I wanted to do it by right-clicking boundary but there are many options like split non-contiguous etc. What should I apply? didn't find the patch option in boundaries.

or should I JUST apply all the boundary condition in the meshing tutorial, will it work?
Another thing if I check the boundary edit option, there's a blank beside PARTS SURFACE, what to do with it? Attachment 76660
Thanks again for explaining it so clearly.

LuckyTran April 19, 2020 06:27

Did I tell you to put anything in parts surface? No. Leave the parts surfaces alone.

You can split by non-contiguous. Probably nothing will happen because all your surfaces look contiguous to me.

You'll have to split by angle or split by function. Try split by angle. Put a pretty high angle so that curved surfaces don't get split into a bunch of little triangles. The default is 89 degrees, which will split surfaces that are sharp corners. If this isn't enough, lower it gradually.

Marium April 19, 2020 06:51

okay I'm trying.
Let's see if I can get through it.
Thanks for being so patient

Marium April 19, 2020 10:25

3 Attachment(s)
it ran for about 15 mins, this error came up. How can I solve this problem?Attachment 76662

Also the free surface is in quite lower side I have set the iso value 0.5. Can it be repaired now?Attachment 76663Attachment 76664

It seems that I can not set the origin in draft line and as I have exported it from other software, the size got bigger. I can not fathom the coordinate of the draft line and ship origin

mazhar16823 April 22, 2020 09:26

You can go to repair surface to see what's wrong with your geometry. The error indicates that it's not ''repaired'' so might have some geometry issues. Once repaired, remesh it.

Marium April 23, 2020 00:10

is there any way I can identify and relocate the origin in starccm+?

Marium April 28, 2020 02:24

Hello,
your advice really helped me. sorry to bother you again but the simulation is not going after 252 iterations. The problem what I am facing now is that after running 40 mins/252 iterations it shows error implying that there is non-positive volume cell Negative volume and the expanded error message shows reversed flow and matrices problem.
Is there any way I can solve it? I have diagnosed the mesh before running, it said NO NEGATIVE VOLUME CELL and mesh is valid.
Thanks again.


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