mesh_skin operator in Mechanical DPF extracts contact elements – area doubled

[felix.kaule]

Hello everyone,

I’m using Ansys Mechanical 2024 R2  and want to calculate the surface area of my Tet10 mesh via the mesh_skin operator. However, the result includes contact elements (CONTA*/TARGE*), which leads to approximately twice the expected area.

My Code:
python
skin_mesh = dpf.operators.mesh.skin(
    mesh=sub_mesh,
    mesh_scoping=node_scoping
).outputs.mesh.GetData()
area_field = dpf.operators.geo.surface_area(mesh=skin_mesh).outputs.fields_container.GetData()[0]


Expected: Only the true boundary faces of the Tet10 elements.
Actual: Additional faces from contact elements are included.

What I tried:

• Filtering by mapdl_element_type_id via scoping.on_property

• Using mesh.faces instead of mesh.skin

• Explicit element vs. nodal scoping

Question:
How can I exclude contact elements from the skin mesh extraction so that only the structural boundary faces remain?

Thanks in advance for your help!

Best regards,
Felix

[Lydia]

Hi Felix,

For DPF and scripting related questions, you should go ahead and ask in the Ansys Developers Forum Home - Community Forum. 

Thank you for your understanding.

Regards,

Lydia

[felix.kaule]

Hello Lydia,

actually that's what I already did, you can delete this thread here if you want.

Regards
Felix

[OmarWorthing90]

Poor Bunny

Hello felix.kaule!

from ansys.dpf import core as dpf

# Filter out contact elements (e.g., type IDs for CONTA/TARGE are usually 100+)
element_types_to_keep = [1, 2, 3, 4, 5]  # Structural types (adjust based on your model)

filtered_mesh_op = dpf.operators.mesh.mesh_filter()
filtered_mesh_op.inputs.mesh.connect(sub_mesh)
filtered_mesh_op.inputs.element_type.connect(element_types_to_keep)
filtered_mesh = filtered_mesh_op.outputs.mesh()

# Now apply skin and surface area
skin_mesh = dpf.operators.mesh.skin(mesh=filtered_mesh).outputs.mesh.GetData()
area_field = dpf.operators.geo.surface_area(mesh=skin_mesh).outputs.fields_container.GetData()[0]