implantation virtual stent

[Ehsan ABC]

HI Sir,
I want to simulate a brain artery by virtual implantation a stent. I have some problem as below:
1. After I imported the artery .stl model and extract face, it divided into several faces but I need one wall and tow caps.
2. After I imported the stent .stl model and extract face,It takes too long to extract faces.
3. how to define outlet condition pressure=0.

[Joseph Roshan]

I have the same problem. In fact, after importing an artery in STL fromat into the SV, there are lots of faces after “extract feces” command. Besides, importing an stent is very problematic as you mentioned! Regarding the outlet pressure, you could notice that SV is subjected to physiologic BC conditions! In case you want to manually charge the outlet pressure with zero, there should be a way, but I could not remind any!

[Hongzhi Lan]

Hi,

For an artery in STL, you may get more faces than you want after "Extract Faces". In this case, you can select some faces and combine them to one face using "Combine".

For a stent, which truly has a lot of faces, SimVascular does extract many faces. Could you tell me why you want to extract faces on a stent?

In Simulation tool, go to Inlet and Outlet BCs, you can specify BC for each cap face there including Distal Pressure (0 by default).

Hongzhi
SimVascular Development Team

[Joseph Roshan]

Thanks for your reply,
I’ll test combining the faces.
Regarding the stent issue, would you pls tell me how to define for SV that stent is a “wall” so that it could be placed within the parent artery of a brain aneurysm?! SV must undrestand that stent is a solid positioned under the neck of the aneurysm within the medium(parent artery).

[Joseph Roshan]

Would you pls give a response?!
I’ve trouble to treat the stent for FSI modeling too! How could SV understand that stent is a solid?!

[Rudolf Hellmuth]

I you want to edit STLs, I would recommend you Blender.

[gang fang]

Hi, Developers
I have the similar question about this theme like https://cfd.gmu.edu/~jcebral/highlight.html

for example , I have two stl format model , one is vessel and the other is stent mesh, How can I import the two model to SV and do CFD together?
Thank you all!

Best,
Gang

[David Parker]

Hi Gang,

You will need to use solid modeling software to subtract the stent solid model from the vessel solid model using a Boolean operation. You can use SolidWorks or FreeCAD to do this.

Cheers,
Dave

[gang fang]

Hi, David,
Thank you for still working now.
I have done the solid boolean cutting that the stent has been cut from vessel.
I have imported the STL to SV model part, and it will seperate the face by angle(50 in default). as you know , there is very huge number of faces on stent wall, so the SV can nearly not process.
I don't know what to do next based on SV for this target. Any advice?
Model file link is https://drive.google.com/open?id=1yEiyT ... ExRXiM3ylM

Best Regards,
Gang

[David Parker]

Hi Gang,

That is a complicated model, 967 faces!

SV Modeling tool was taking forever to show faces in the Face List table for models with a large number of faces. The latest 2020-02 SV release fixes that problem. Rotating the model is still a bit slow. I have a fix for that and will create new installers for it today for Ubuntu and MacOS.

I was able to set the faces to cap and wall, but I was not able to mesh the model, got the error

Code: Select all

Creating surface mesh ...
Found two nearly self-intersecting facets.
  1st: [71024, 70562, 70894] #669
  2nd: [71024, 70562, 71166] #669
The dihedral angle between them is 0.0350315 degree.

so there seems to be a problem with the STL model.

I suggest creating a simpler model, like a cylinder with a stent and see if SV can mesh it.

Cheers,
Dave