Preprocessing

Preprocessing

Mesh Generation Errors

    • b0baganush
      Subscriber

      I am having an issue when I try to generate a mesh on my model for Fluent. Everything I seem to find online basically states that Ansys wasn't installed correctly and to reinstall it and there is no real fix. 


      I import my model (I have tried .stl and .iges files) into space claim and then click over to generate the mesh. When the Mesh program opens I receive the error "PlugIn Error: Failed to import assembly from spaceclaim. No bodies to transfer." I tried reducing the number of triangles in the model and when I do that I receive the error "The mesh generation did not complete due to poor quality elements or incorrect input."


      Is there a fix to these issues or could someone explain to me why they are happening so that I can try to fix my models. 


      Not sure if it matters but the model was made in a CAD software called 3-Matics by Materialise.

    • peteroznewman
      Subscriber

      When you import a .stl file into SpaceClaim, it imports as a Facet Body, which cannot be meshed in the Mesh component.


      In SpaceClaim, go to the Facets tab and click the Check Facets tool, then click on the Facet Body.


      Reply with the results, such as this:



      You can use the Auto Fix tool to try to improve the situation.


      When the defects are fixed, you right mouse button on the Facet Body and Convert to Solid.


      This can be meshed in the Mesh component.

    • b0baganush
      Subscriber

      Thank you for the post. Below is the screenshot of the Check Facets screen for me. 



      It looks like the right clicking and converting to solid has stopped the error messages from showing up but when I open the meshing program nothing shows up. There is a flashing red stop sign at the bottom of the screen that when I click on it says that saving is disabled for bodies over x number of faces. Does this mean that I need to save the SpaceClaim file before I can import it into the meshing?

    • peteroznewman
      Subscriber

      You are on the free ANSYS Student license where there is a 300 face limit for geometry. You have 1016 faces.


      I am fortunate to have a full license and I want to practice my SpaceClaim skills to reduce the number of faces. If you are willing to put your STL file in a zip file, you can attach the zip file after you post your reply and I will have a go at returning a solid with < 300 faces that you can mesh.

    • b0baganush
      Subscriber

      Thank you for the offer. Unfortunately the model I am using is from a clinical patient that is being used for medical research. Due to HIPAA laws in the United States I cannot provide the model. If I was able to reduce the number of faces and save the part it should theoretically mesh correct? Thanks for your help.

    • peteroznewman
      Subscriber

      I understand HIPAA laws very well. You can share clinical data being used for medical research as long as the data have been de-identified and there is no Private Health Information included. An STL file with a random file name would be a good example of that.


      You can save the part if the number of faces is < 300.  You can open the STL file with more than 300 facets, and use the Facets tools to reduce the number of facets, or better yet, create a small number of surfaces using the Skin tool to cover the STL facets.  You can eventually close the surfaces to make a solid. Or try the Shrinkwrap tool.

    • b0baganush
      Subscriber

      Thanks for the clarification. I have attached the main model that I would like to test with.

    • peteroznewman
      Subscriber

      Are you on 2019 R2?  Please reply with the version you are using since if you are on an older version, you can't open files created in the newer version.

    • b0baganush
      Subscriber

      Yes I am using 2019 R2

    • peteroznewman
      Subscriber

      As I said, I am just practicing how to use the Skin Tool.



      I  think you can do what I just did, but on the student version. Just hide the solid and try again.

    • b0baganush
      Subscriber

      Awesome this seems to be working! Thank you for your help with this.

    • peteroznewman
      Subscriber

      You will want to slice a thin layer off the one face that covers the circular region that would be an inlet or outlet.  I did that and tried the new Watertight Meshing. 


      name id skewed-cells(> 0.90) maximum-skewness cell count








      aneurysm-skinned-solid:68 68 0 0.85048935 276117


       


      name id skewed-cells(> 0.90) maximum-skewness cell count








      Overall Summary none 0 0.85048935 276117


       



      276117 cells were created in : 0.93 minutes


       



      The mesh has a minimum Orthogonal Quality of: 0.15.


      Here is the polygon mesh with 3 elements through the boundary layer.


    • cfd_user12
      Subscriber
      Dear Peter,nI have the same problem too. i'm working wiht the 2020 R2 version on a bone scaffold and when import it in Fluent it import the file as facets body. I tried to use Skin tool but it doesn't work with a 3d geometry. Could you help me to convert my facets body in a solid Body?n
Viewing 12 reply threads
  • You must be logged in to reply to this topic.