[AndreasW]

Hi,

I'm currently investigating aeroacoustics of a rather complex geometry, that requires highly resolved 3D LES Simulation, which I'm performing in Ansys Fluent.

For Meshing I currently use Ansys Workbench Meshing to create a (unstructured Delaunay) tetrahedral mesh or in some regions if possible a hexcore mesh using the MultiZone algorithm.

As the resulting mesh quality is rather poor I wonder if a cartesian octree mesh would yield better results. What i aim for is a mesh similar to what is shown in Picture 5 in [1], which i attached to this post.

As Ansys Workbench Meshing can't create octree meshes to my knowledge, I tried to use the Rapid Octree Algorithm of Fluent Meshing, but unfortunately I can't get it working for any geometry.

As a simple example i tried to mesh a sphere, but Fluent meshing always shows an error, that the geometry (the simple sphere) is not watertight. If I use the watertight meshing workflow however, it works just fine.

I couldn't find any tutorial on how to generate a cartesian non-conformal octree mesh.

I hope some of you can help me or point me to where i can find instructions on how to use this meshing tool.

Best regards
Andreas

[1] Oswald, M. and Sovani, S., 2015. Aero-Vibro-Acoustics For Wind Noise Applications. In 2015 Automotive Simulation World Congress.