Extract mesh surfaces from .STL files

ParaView Support
1

Hi there!

Very silly problem here. But unfortunately i haven’t founded any solutions yet. I aim to estimate the flow rate at some 2D-surfaces internal to my mesh (i.e no boundaries or inlet-outlet patch), using the filter SurfaceFlow. Could do it by taking different slices, but in this way it’s going to be too laborious.

I have instead the .STL files of these internal surfaces (made it by FreeCAD). Basically internal circular holes of my burner. Can i so extract surfaces from my computed mesh that coincide with my STL geometry? Following what method, in case?

Hope to have been clear enough.

2

ResampleWithDataSet should be what you are looking for.

3

Thank you Matt! Unfortunately i’m not still be able to manage my issue. As you can see my internal surface (.STL, blue circle) is entirely contained in my mesh domain (grey region).

first
first972×767 355 KB

Then i apply as you have suggested the ResampleWithDataSet command (hopefully in the right way):

Screenshot from 2024-12-19 13-39-22
Screenshot from 2024-12-19 13-40-27

Eventually it actually extracts my internal surface. But with no fluid data on it (and therefore i cannot estimate anything).

Screenshot from 2024-12-19 13-41-11
Screenshot from 2024-12-19 13-41-111280×1024 158 KB

Surely i have made a trivial mistake. But i don’t see where.

4

Please share your data

5

About what? Have i to upload my complete simulation?

6

Yes, you can create an archive and share it on wetransfer.

7

What e-mail address? Should i pay for this service?

8

mathieu.westphal@kitware.com (but I dont think its needed). Its free up to 2G I think.

9

I confirm that we cannot use ResampleWithDataSet with your volume.

However you can use Slice trivially since your stl is an axis-aligned plane. Just press P to position a Y-normaled slice.

Here is the resulting state file:
slice.pvsm (1014.4 KB)

image
image2107×1095 74.4 KB

10

Gusp :cold_sweat:! What i’ve posted before were just an example. I have to compute the flow rate for the holes of my burner crown (the circles in the middle):

second
second972×767 37.9 KB

Is there a smart way to select one by one each of them?

11

Sure, modify the threshold filter or add more threshold to select the right regions