[surface handling] How to make boundary patches in STL file

nzy102 · August 29, 2008, 02:48

Hello:

First, thank openfoam team for the wondful tool snappyhexmesh. I am working on meshing a quite geometry now. I made the geometry from solidworks. Then converted the solidworks file to STL. The problem with solidworks is it exported the geometry as a whole surface. So I couldn't make patches in the stl file. As a workaround, I imported the stl file in Rhino and saved every surface (patch) as a stl file in ASCII format. Then I put all the stil files together (integrated stl file). When I ran snappyhexmesh, I got something like:

===============================================
Shell **** does not support testing for inside
Probably it is not closed
================================================

I went back to open the integrated stl file in several different softwares ( blender, rhino and solidworks) and it looked that the stl file is closed. Does anybody here has a similar problem?

Is there any other way to makes patches for STL files in general?

Thank you so much.

mattijs · August 29, 2008, 04:48

To use inside/outside we require every edge to have exactly two faces using it. Load in paraview, Filter->Feature Edges and switch on the 'non-manifold' edges. Disable all sharp angle ones (by setting angle to 180?).

nzy102 · August 29, 2008, 13:53

Hi Mattijs:

It gave me the same error.

Ning

CoSponge · January 8, 2015, 07:56

Hi,

have you checked if every single solid has the exact syntax? I mean this one:

solid <name>
facet normal 0 1 0
outer loop
vertex -0.019754 -0.15 0.103129
vertex -0.02 -0.15 0.1
vertex -0.019754 -0.15 0.096871
endloop
endfacet
endsolid

Maybe you miss "endsolid" at the end while putting everything toghether. Let me know

Cheers

Julie

Cagatayemre · January 22, 2018, 15:03

I have just used SolidWorks to create stl and boundary patches. But in stl file there are the following lines

solid cylinder_small
facet normal 6.752258e-002 0.000000e+000 -9.977177e-001
outer loop
vertex -1.000000e-001 -5.000000e-004 -1.000000e-002
vertex -9.898832e-002 5.000000e-004 -9.948693e-003
vertex -9.898832e-002 -5.000000e-004 -9.948693e-003
endloop
endfacet

6.752258e-002
-9.977177e-001
I think these numbers creates problem in snappyHexMesh process. Maybe we should try another software to create geometry and mesh such as Salome. Any help will be appreciated.

August 29, 2008, 02:48	How to make boundary patches in STL file	#1
nzy102 Member Ning Yang Join Date: Mar 2009 Location: University Park, PA, USA Posts: 84 Rep Power: 17	Hello: First, thank openfoam team for the wondful tool snappyhexmesh. I am working on meshing a quite geometry now. I made the geometry from solidworks. Then converted the solidworks file to STL. The problem with solidworks is it exported the geometry as a whole surface. So I couldn't make patches in the stl file. As a workaround, I imported the stl file in Rhino and saved every surface (patch) as a stl file in ASCII format. Then I put all the stil files together (integrated stl file). When I ran snappyhexmesh, I got something like: =============================================== Shell **** does not support testing for inside Probably it is not closed ================================================ I went back to open the integrated stl file in several different softwares ( blender, rhino and solidworks) and it looked that the stl file is closed. Does anybody here has a similar problem? Is there any other way to makes patches for STL files in general? Thank you so much.

August 29, 2008, 04:48	To use inside/outside we requi	#2
mattijs Senior Member Mattijs Janssens Join Date: Mar 2009 Posts: 1,419 Rep Power: 26	To use inside/outside we require every edge to have exactly two faces using it. Load in paraview, Filter->Feature Edges and switch on the 'non-manifold' edges. Disable all sharp angle ones (by setting angle to 180?).

August 29, 2008, 13:53	Hi Mattijs: It gave me the	#3
nzy102 Member Ning Yang Join Date: Mar 2009 Location: University Park, PA, USA Posts: 84 Rep Power: 17	Hi Mattijs: It gave me the same error. Ning

January 8, 2015, 07:56	Close stl file	#4
CoSponge New Member Julie Correncon Join Date: Oct 2014 Posts: 7 Rep Power: 11	Hi, have you checked if every single solid has the exact syntax? I mean this one: solid <name> facet normal 0 1 0 outer loop vertex -0.019754 -0.15 0.103129 vertex -0.02 -0.15 0.1 vertex -0.019754 -0.15 0.096871 endloop endfacet endsolid Maybe you miss "endsolid" at the end while putting everything toghether. Let me know Cheers Julie

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[Other] Tabulated thermophysicalProperties library	chriss85	OpenFOAM Community Contributions	62	October 2, 2022 03:50
[swak4Foam] Installation Problem with OF 6 version	Aurel	OpenFOAM Community Contributions	14	November 18, 2020 16:18
what is swap4foam ??	AB08	OpenFOAM	28	February 2, 2016 01:22
SparceImage v1.7.x Issue on MAC OS X	rcarmi	OpenFOAM Installation	4	August 14, 2014 06:42
friction forces icoFoam	ofslcm	OpenFOAM	3	April 7, 2012 10:57

January 22, 2018, 15:03		#5
Cagatayemre Member Çağatay Emre Ayhan Join Date: Sep 2017 Location: Istanbul, Turkey Posts: 31 Rep Power: 8	I have just used SolidWorks to create stl and boundary patches. But in stl file there are the following lines solid cylinder_small facet normal 6.752258e-002 0.000000e+000 -9.977177e-001 outer loop vertex -1.000000e-001 -5.000000e-004 -1.000000e-002 vertex -9.898832e-002 5.000000e-004 -9.948693e-003 vertex -9.898832e-002 -5.000000e-004 -9.948693e-003 endloop endfacet 6.752258e-002 -9.977177e-001 I think these numbers creates problem in snappyHexMesh process. Maybe we should try another software to create geometry and mesh such as Salome. Any help will be appreciated.