[ICEM] Meshing .stl surface in ICEM

kbodla · June 22, 2010, 16:39

Hi..,
I have just recently begun ICEM and would like to know how would one import an .stl surface mesh and generate a volume mesh for the corresponding volume bound by the surface.

Thanks,

Karthik

PSYMN · June 23, 2010, 14:44

There are several tutorials for this exact thing...

File => Import Geometry => STL.

Then "Geometry (tab) => Repair Geometry => Build Diagnostic Topology" to get your curves and segment the faceted geometry by feature angle.

Then right click on parts in the model tree to create new parts (Such as INLET, Outlet, etc.) and add the surface segments to the correct parts.

Create a material point or whatever...

Set sizes.

Hit the button to Compute mesh (using Octree Tetra)

Other than the Import part (which is pretty straight forward), you can see the process at www.youtube.com/ansysinc

I recommend all new users go thru the tutorials before getting yourself frustrated and stuck on your own model.

Simon

calvin123 · December 2, 2010, 21:33

Hi PSYMN,
I agree with you, it is better to read tutorials first. I am a newer of ICEM too, and I cannot locate whereabout the tutorial manuals, could you please let me know?
I also need to import STL file in ICEM (I tried in Gambit, but it is hopeless of Gambit

).
For my model (human body shape; the geometry is done by other software), I import STL in ICEM and it seems fine, then when I mesh it, I cannot see the human body is meshed, but only the flow domain

.
Could you suggest any possible ways to get the mesh created, please?
Many thanks.

PSYMN · January 30, 2011, 18:26

ICEM CFD controls which bodies are meshed by the location of material points. If you put one inside the body, then that region is meshed. If you put one outside the body, then that region is meshed. If you put both, then both regions are meshed...

ld1305 · January 16, 2012, 09:14

Hi,

I've recently begun work on something similar, however I'm having issues creating inlets and outlets, is there any more detailed instruction available?

Thanks very much

PSYMN · January 16, 2012, 09:35

Calvin123, I missed your previous comment about not being able to select the inlet and outlet...

The problems is that your STL is all one surface, so when you try to select it, you get the whole thing...

As is often the case, there are a number of solutions. If your inlets and outlets are separated by sharp angles, use "Geometry (tab) => Repair => Build Diagnostic Topology". This tool will break up the STL into separate surfaces based on the angle specified. It can also add curves and points based on that angle, which is great for Tetra/Prism. Once the STL surface is broken up into separate surfaces, you can come back and put the inlet into an inlet part, etc.

If you have regions that you want to separate, but which do not have nature feature angles to automate the break up, there are a number of other methods. Most of the geometry tools (such as split surface at a plane) work with STL geometry also. You can also use the geometry repair tools to split STL or even to select facet by facet (or use the polygon select tool) and "Move to New Part".

PSYMN · January 16, 2012, 09:36

Lauren,

Please be more specific. Were you just having trouble breaking up the STL surface? The previous comment should help.

Best regards,

Simon

Lilly · June 28, 2012, 13:24

Dear all,

I am a bit confused about the *.stl-meshing at the moment.
When I do "Build Topology" and the curves and points appear on my surface, do I have to erase them later on again? Or are they a sign for a "bad geometry"?
I realized that my surface includes several small surfaces afterwards (due to the curves that appear). Do I have to merge them again or does this not have any influence on the quality of my mesh?
I couldn't find the mentioned tutorials for meshing *.stls. Can anybody maybe post a link please?
Thanks a million for any help!
Lilly

Malthehh · January 19, 2018, 02:10

Hi Lilly
I am just working with the same thing right now

I hope that you found a solution to your problem.

If you open ICEM - Go to help userguide:
- ICEM CFD
- Tutorials
- Tetra/Prism Mesh Generation for an Aorta

You can also take a look at the other tutorials which are given in the userguide.

crayon · January 7, 2019, 21:40

Hi calvin,

Recently I need to model human breast (segmented from MR image) and import it to Ansys ICEM for meshing. I do the segmentation in 3DSlicer but found the output was surface mesh, not geometry. I want to know how you model your human body shape. What software did you use (better in modeling with medical image)?
Hope for some advice, thank you!

Crayon

Malthehh · January 20, 2019, 11:22

Hi Crayon. I am not sure of what you mean. But I will try to answer you question.

In my master thesis, I got the human breast model as a STL geometry from my supervisor, which I then could modify in ICEM and Spaceclaim. I use Spaceclaim to make plane surfaces at bronchies, so I could define these as outles. The same thing at the oral and nasal openinings. Spaceclaim should also repair all the "holes" and other scannings mistakes which I found as a neccerary tool to make my geometry/mesh work.
- Most of the functions with creating surfaces you can also do i ICEM, which I actually found most easy to work with.

- If you look though the tutorials is ICEM there is a tutorial of how to create a mesh by a STL file. It was VERY helpful for my work.

crayon · January 21, 2019, 00:21

Hi Malthe. Thanks for your reply.

I have segmented my human breast model from MR image (in 3DSlicer) and got a surface mesh. Is your STL geometry a mesh (surface or volumetric mesh?) or a solid? I think that STL formats are mostly mesh files?

I have also looked through the tutorials (https://www.sharcnet.ca/Software/Ans...sermanual.html) and tried to import the STL files to ICEM (My workflow: File-Import Geometry-Faceted-STL, import options Part names "Generate" and "From file" were both tried). But the result turned out badly. The following figures are two results in Solidworks (normally displayed) and ICEM. I have no idea why the import failed. Could you give me some advice? Thank you very much.

Best regards,
Crayon

AtoHM · January 21, 2019, 02:28

If you have Solidworks at hand, try to create a solid body from the STL you have (there is an import option for STL to import as solid body and also a checking tool somewhere). Then save it as step file and import it with ICEM.

Ludvik · January 21, 2019, 06:16

Import looks correct.
Just change type of presentation. (Geometry> Surface > RMB "Show Full")

crayon · April 17, 2019, 08:21

Dear all,

I have generated a tetrahedral volumetric mesh of a bounding box (nearly a cuboid) using ICEM. I wonder how to extract the coordinate of the nodes located at the boundary of the bounding box. I want to generate the displacement of these nodes (by combination with other displacement vector fields) and use them as constraint of subsequent fem boundary condition (the following work will be done in Ansys).
Could anyone give some advice? Your help is greatly appreciated!

Crayon

@Arash · May 9, 2023, 14:42

Hi Simon Pereira,

I have a 3D STL geometry file and I want to create an structured mesh on it. Is it possible?
I opened the STL file in ICEM according to the command you gave and selected the Build Diagnostic Topology, then obtained some curves from the geometry and tried to block and create a structure mesh, but after generating the mesh,
The mesh looks unusual and broken in some areas. After selecting the Build Diagnostic Topology option, should I do something else and then block the geometry?

Any help is appreciated.

@Arash · May 9, 2023, 14:45

Quote:

Originally Posted by PSYMN

There are several tutorials for this exact thing...

File => Import Geometry => STL.

Then "Geometry (tab) => Repair Geometry => Build Diagnostic Topology" to get your curves and segment the faceted geometry by feature angle.

Then right click on parts in the model tree to create new parts (Such as INLET, Outlet, etc.) and add the surface segments to the correct parts.

Create a material point or whatever...

Set sizes.

Hit the button to Compute mesh (using Octree Tetra)

Other than the Import part (which is pretty straight forward), you can see the process at www.youtube.com/ansysinc

I recommend all new users go thru the tutorials before getting yourself frustrated and stuck on your own model.

Simon

Hi Simon Pereira,

I have a 3D STL geometry file and I want to create an structured mesh on it. Is it possible?
I opened the STL file in ICEM according to the command you gave and selected the Build Diagnostic Topology, then obtained some curves from the geometry and tried to block and create a structure mesh, but after generating the mesh,
The mesh looks unusual and broken in some areas. After selecting the Build Diagnostic Topology option, should I do something else and then block the geometry?

Any help is appreciated.

June 22, 2010, 16:39	Meshing .stl surface in ICEM	#1
kbodla New Member karthik Join Date: Jun 2010 Posts: 3 Rep Power: 15	Hi.., I have just recently begun ICEM and would like to know how would one import an .stl surface mesh and generate a volume mesh for the corresponding volume bound by the surface. Thanks, Karthik

June 23, 2010, 14:44	Steps	#2
PSYMN Senior Member Simon Pereira Join Date: Mar 2009 Location: Ann Arbor, MI Posts: 2,663 Blog Entries: 1 Rep Power: 47	There are several tutorials for this exact thing... File => Import Geometry => STL. Then "Geometry (tab) => Repair Geometry => Build Diagnostic Topology" to get your curves and segment the faceted geometry by feature angle. Then right click on parts in the model tree to create new parts (Such as INLET, Outlet, etc.) and add the surface segments to the correct parts. Create a material point or whatever... Set sizes. Hit the button to Compute mesh (using Octree Tetra) Other than the Import part (which is pretty straight forward), you can see the process at www.youtube.com/ansysinc I recommend all new users go thru the tutorials before getting yourself frustrated and stuck on your own model. Simon

December 2, 2010, 21:33	ICEM tutorial	#3
calvin123 New Member calvin Join Date: Nov 2010 Posts: 12 Rep Power: 15	Hi PSYMN, I agree with you, it is better to read tutorials first. I am a newer of ICEM too, and I cannot locate whereabout the tutorial manuals, could you please let me know? I also need to import STL file in ICEM (I tried in Gambit, but it is hopeless of Gambit). For my model (human body shape; the geometry is done by other software), I import STL in ICEM and it seems fine, then when I mesh it, I cannot see the human body is meshed, but only the flow domain. Could you suggest any possible ways to get the mesh created, please? Many thanks.

January 30, 2011, 18:26	Material Points.	#4
PSYMN Senior Member Simon Pereira Join Date: Mar 2009 Location: Ann Arbor, MI Posts: 2,663 Blog Entries: 1 Rep Power: 47	ICEM CFD controls which bodies are meshed by the location of material points. If you put one inside the body, then that region is meshed. If you put one outside the body, then that region is meshed. If you put both, then both regions are meshed...

January 16, 2012, 09:35		#6
PSYMN Senior Member Simon Pereira Join Date: Mar 2009 Location: Ann Arbor, MI Posts: 2,663 Blog Entries: 1 Rep Power: 47	Calvin123, I missed your previous comment about not being able to select the inlet and outlet... The problems is that your STL is all one surface, so when you try to select it, you get the whole thing... As is often the case, there are a number of solutions. If your inlets and outlets are separated by sharp angles, use "Geometry (tab) => Repair => Build Diagnostic Topology". This tool will break up the STL into separate surfaces based on the angle specified. It can also add curves and points based on that angle, which is great for Tetra/Prism. Once the STL surface is broken up into separate surfaces, you can come back and put the inlet into an inlet part, etc. If you have regions that you want to separate, but which do not have nature feature angles to automate the break up, there are a number of other methods. Most of the geometry tools (such as split surface at a plane) work with STL geometry also. You can also use the geometry repair tools to split STL or even to select facet by facet (or use the polygon select tool) and "Move to New Part". __________________ ----------------------------------------- Please help guide development at ANSYS by filling in these surveys Public ANSYS ICEM CFD Users Survey This second one is more general (Gambit, TGrid and ANSYS Meshing users welcome)... CFD Online Users Survey

January 16, 2012, 09:14		#5
ld1305 Member Lauren Dransfield Join Date: Jan 2012 Posts: 50 Rep Power: 14	Hi, I've recently begun work on something similar, however I'm having issues creating inlets and outlets, is there any more detailed instruction available? Thanks very much

January 16, 2012, 09:36		#7
PSYMN Senior Member Simon Pereira Join Date: Mar 2009 Location: Ann Arbor, MI Posts: 2,663 Blog Entries: 1 Rep Power: 47	Lauren, Please be more specific. Were you just having trouble breaking up the STL surface? The previous comment should help. Best regards, Simon __________________ ----------------------------------------- Please help guide development at ANSYS by filling in these surveys Public ANSYS ICEM CFD Users Survey This second one is more general (Gambit, TGrid and ANSYS Meshing users welcome)... CFD Online Users Survey

June 28, 2012, 13:24		#8
Lilly Senior Member Join Date: Feb 2011 Posts: 140 Rep Power: 15	Dear all, I am a bit confused about the .stl-meshing at the moment. When I do "Build Topology" and the curves and points appear on my surface, do I have to erase them later on again? Or are they a sign for a "bad geometry"? I realized that my surface includes several small surfaces afterwards (due to the curves that appear). Do I have to merge them again or does this not have any influence on the quality of my mesh? I couldn't find the mentioned tutorials for meshing .stls. Can anybody maybe post a link please? Thanks a million for any help! Lilly

January 19, 2018, 02:10		#9
Malthehh New Member Malthe Haahr Hvelplund Join Date: Oct 2017 Location: Aalborg, Denmark Posts: 12 Rep Power: 8	Hi Lilly I am just working with the same thing right now I hope that you found a solution to your problem. If you open ICEM - Go to help userguide: - ICEM CFD - Tutorials - Tetra/Prism Mesh Generation for an Aorta You can also take a look at the other tutorials which are given in the userguide.

January 7, 2019, 21:40		#10
crayon New Member xinxie Join Date: Jan 2019 Posts: 5 Rep Power: 7	Hi calvin, Recently I need to model human breast (segmented from MR image) and import it to Ansys ICEM for meshing. I do the segmentation in 3DSlicer but found the output was surface mesh, not geometry. I want to know how you model your human body shape. What software did you use (better in modeling with medical image)? Hope for some advice, thank you! Crayon

January 20, 2019, 11:22		#11
Malthehh New Member Malthe Haahr Hvelplund Join Date: Oct 2017 Location: Aalborg, Denmark Posts: 12 Rep Power: 8	Hi Crayon. I am not sure of what you mean. But I will try to answer you question. In my master thesis, I got the human breast model as a STL geometry from my supervisor, which I then could modify in ICEM and Spaceclaim. I use Spaceclaim to make plane surfaces at bronchies, so I could define these as outles. The same thing at the oral and nasal openinings. Spaceclaim should also repair all the "holes" and other scannings mistakes which I found as a neccerary tool to make my geometry/mesh work. - Most of the functions with creating surfaces you can also do i ICEM, which I actually found most easy to work with. - If you look though the tutorials is ICEM there is a tutorial of how to create a mesh by a STL file. It was VERY helpful for my work.

January 21, 2019, 00:21		#12
crayon New Member xinxie Join Date: Jan 2019 Posts: 5 Rep Power: 7	Hi Malthe. Thanks for your reply. I have segmented my human breast model from MR image (in 3DSlicer) and got a surface mesh. Is your STL geometry a mesh (surface or volumetric mesh?) or a solid? I think that STL formats are mostly mesh files? I have also looked through the tutorials (https://www.sharcnet.ca/Software/Ans...sermanual.html) and tried to import the STL files to ICEM (My workflow: File-Import Geometry-Faceted-STL, import options Part names "Generate" and "From file" were both tried). But the result turned out badly. The following figures are two results in Solidworks (normally displayed) and ICEM. I have no idea why the import failed. Could you give me some advice? Thank you very much. Best regards, Crayon

January 21, 2019, 02:28		#13
AtoHM Senior Member M Join Date: Dec 2017 Posts: 642 Rep Power: 12	If you have Solidworks at hand, try to create a solid body from the STL you have (there is an import option for STL to import as solid body and also a checking tool somewhere). Then save it as step file and import it with ICEM.

January 21, 2019, 06:16		#14
Ludvik Member Join Date: Apr 2009 Location: Czech Republic Posts: 65 Rep Power: 18	Import looks correct. Just change type of presentation. (Geometry> Surface > RMB "Show Full")

April 17, 2019, 08:21		#15
crayon New Member xinxie Join Date: Jan 2019 Posts: 5 Rep Power: 7	Dear all, I have generated a tetrahedral volumetric mesh of a bounding box (nearly a cuboid) using ICEM. I wonder how to extract the coordinate of the nodes located at the boundary of the bounding box. I want to generate the displacement of these nodes (by combination with other displacement vector fields) and use them as constraint of subsequent fem boundary condition (the following work will be done in Ansys). Could anyone give some advice? Your help is greatly appreciated! Crayon

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[Gmsh] Problem with Gmsh	nishant_hull	OpenFOAM Meshing & Mesh Conversion	23	August 5, 2015 02:09
problem with surface creation in ICEM from multiple curves	dialolema	ANSYS Meshing & Geometry	2	October 27, 2014 13:14
[ICEM] 2d Aerofoil meshing in ansys ICEM	syler3321	ANSYS Meshing & Geometry	2	February 3, 2012 01:59
[Gmsh] boundaries with gmshToFoam‏	ouafa	OpenFOAM Meshing & Mesh Conversion	7	May 21, 2010 12:43
[ICEM] Need help in ICEM CFD Mapped Meshing	falconf16	ANSYS Meshing & Geometry	3	February 19, 2010 14:21

May 9, 2023, 14:42		#16
@Arash Member Join Date: Oct 2022 Posts: 61 Rep Power: 3	Hi Simon Pereira, I have a 3D STL geometry file and I want to create an structured mesh on it. Is it possible? I opened the STL file in ICEM according to the command you gave and selected the Build Diagnostic Topology, then obtained some curves from the geometry and tried to block and create a structure mesh, but after generating the mesh, The mesh looks unusual and broken in some areas. After selecting the Build Diagnostic Topology option, should I do something else and then block the geometry? Any help is appreciated.