Flow Analysis Domain Icon Colors (Creo 7.0.9.0)

[GV_10691043]

Hi. What do the different domain icon colors mean? I've noticed after meshing they can change from the bluish color they normally are. I know I've at least seen green (pictured here) and gray. For the model I'm currently working on, the green icon domains do not let me view any properties (e.g., temperature). Thanks. It would be really nice if there was a place to look up all this stuff that's not explained in help. 

[tmoser · Accepted solution]

I think it means that Creo Flow didn't creat any mesh for that domain. You may need to update that domains or even recreate it.

[GV_10691043]

I see. Looking at my streamlines that does seem to be the case. Thanks so much!

[cfdgeek]

Hi please check the additional domains group in the simulation tree. Some models have some modeling issues, which may lead to gaps and issues when we get the tessellation from the geometry. Those can cause your simulation volume gets the wrong name and will be grouped in the additional domain group. You can still find those back and setup material property manually and then continue working on your simulation.

[GV_10691043]

Hi. Is there a way to see why the domains came out as green? I was able to fix the last problem because I found that the geometry hadn't been modeled correctly and there was an intersection between solid domains. In that case, only one of the intersecting domains came out as green; the other one meshed properly. Once I eliminated that intersection everything meshed correctly. But I just had it come up again this morning and there are no intersections between the two parts. and both came out as green. I have no idea what the problem is. I looked in additional domains and it seems like one of the intersecting parts is there in its entirety, but nothing for the other one. I have no idea what's wrong, so I don't know how to fix it. Unfortunately, I can't share the exact setup, but I can sort of describe it. There's a cylindrical insulator with an interior diameter. A very thin model is in contact with the inner diameter of the insulator to act as the heat source. It is the same height and length as the insulator. The are both placed on top of another insulator acting as the base, and the top is left open. The base and the heat source are the two coming out as green, and the base is the one that seemed to be duplicated in the additional domains section. It doesn't give any information, so I have no idea where to even start to figure it out.

[tmoser]

What are your settings for mesh size? You might try to make these settings smaller since you have a very thin part. The following image shows the default settings.

Try these settings

Maximum Cell Size: 0.001

Minimum Cell Size: 0.0001

Cell Size on Surfaces: 0.005

There are also a couple of system variable that might be missing or set to a better value.

CFD_MESH_CONTROL_PERCENT = 0.1

CFD_MERGE_QUALITY = 8

[GV_10691043]

My settings are the same for everything except merge quality which is set to 10. I shortened the heating cylinder slightly so that it's no longer in contact with the base and now the base is getting meshed correctly, but the element isn't. I'll try increasing the thickness and see if that works. I isolated just that part and the insulator around it and started meshing it; it took an incredibly long time to complete the mesh, though. It's hit around 138 million splits and took probably 30-45 minutes. When it's in the full assembly it takes around 10 minutes or less to complete the mesh. I'm guessing that, because the isolated assembly has much less complex geometry, the cells can be much smaller for the simpler geometry and the meshing tries to normalize (or keep relative size) cell size to the largest cell generated. Is that's what happening?

[tmoser]

Could you eliminate the thin part altogether? A heat load can be applied directly to a surface of a domain. In this case, you would apply the heat load to the ID of your insulator. You have to create a new boundary condition on the insulator domain. Right click on the domain in the project tree and pick Add Boundary Condition, then select the ID surface and give the new BC a unique name. You can now apply a heat load or specified temperature directly to that BC.

[GV_10691043]

I had tried that before with a specified temperature and it did not seem to work. As the simulation ran, the temperature went all the way down to ambient. Would using total heat flux be equivalent to creating a total heat source?

[tmoser]

I think the total heat flux would be the same.

When you tried the specified temperature before, was that an initial condition? You would have to apply the specified temperture to the BC on the Heat portion of the Model Tab.

[GV_10691043]

I had set it to both. And I create the boundary conditions and after meshing the option to make it a source was present, so I was able to just make it a source as if it were a domain. All this worked, my sim is up and running now. Thank you very much!

[tmoser]

Glad to hear it!