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Fluent Fault-tolerant Meshing – Pipe with Valve – Mesh Pipe – Void Valve

    • peteroznewman
      Subscriber

      Continued study of the Beta feature in 2019 R2, the Fluent Fault-tolerant meshing.  I created a Tutorial for how to mesh the fluid region in a simple pipe and valve.  On my initial trying out of the workflow, I meshed the fluid region and the pipe and the valve in this discussion.


      Now I am trying to mesh the fluid region and the pipe, but leave the valve as a void. Error messages are produced.


    • Rob
      Ansys Employee

      Looks like the surface mesh hasn't fully sealed the volumes somewhere or is inconsistent.  Try R3 in a short while and/or hassle pgl for some help!  

    • peteroznewman
      Subscriber

      The pipe and valve geometry is a very simple surrogate for a much more complex geometry that an ASC member provided to me. That ASC member has been using ICEM for the last 6 months, but is experiencing some issues. I tried ANSYS Meshing at first, but the geometry is too complex to construct the fluid region from the two solids which interfere slightly. The two solids (which originate as STL files and so are faceted) are too complex for boolean operations to succeed to eliminate the interference between the complex solids. Each complex solid can be meshed individually, and the fluid region can be extracted from one solid: the "pipe".  I tried Fault-tolerant meshing to see if it would work, but it's too early in the development at this time.


      I haven't yet learned about overset mesh, would that allow three separate meshes with interference between them to resolve the interference in the solver?


      What other methods might work on this problem?

    • Rob
      Ansys Employee

      Overset may run into problems due to the various limitations. 


      Have a look at the full Fluent Meshing course: you should be able to use the Intersect tool to split/join/connect to create the bodies. SpaceClaim may also work as it'll read the stl with a full licence. 

    • peteroznewman
      Subscriber

      SpaceClaim on a full license was used to read the stl files and convert them to solids, but it couldn't do the booleans needed to get to a Volume Extract.


      I think the ASC, who is skilled at ICEM, is looking for support from a Fluent Meshing expert to try that code on this challenging geometry.

    • Rob
      Ansys Employee

      Thanks Peter. Can you ask them to log a support ticket? 


      In SC can you work with the surfaces and then create volumes or even not bother with volumes? 

    • peteroznewman
      Subscriber

      The ASC submitted a support ticket on August 7 and he is still waiting for help.


      SpaceClaim has the ability to do booleans on facet bodies. This first time I tried this, it created horrible results. I just realized that the difference in facet size may be the reason for the horrible result and I will try again after increasing the facets on the coarsely faceted body to match the facet size of the finely faceted body, then try the boolean again.

    • Rob
      Ansys Employee

      You can intersect in Fluent Meshing too, it's just not in the workflows. 

    • peteroznewman
      Subscriber

      I was successful increasing the facet count of the coarsely faceted body, then subtracting and uniting the finely faceted body. Now I have two STL files, one of which would be a suitable surface mesh to create a fluid volume from, and another surface mesh for the "pipe" that would have the interference removed from the inserted solid body "valve".  I was also able to convert these to solid bodies, but that is to go down the ANSYS Meshing path and I don't want to do that.


      Now I have to go take some training courses in Fluent Meshing to see what I can do with these STL files.

    • Rob
      Ansys Employee

      Have a look at surface remeshing in Fluent Meshing and "Material Points".  The tree in Fluent Meshing isn't as straightforward as the Workflows but the trade off is for power: think Workbench Mechanical v APDL. 

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