Plotting a displacement field from a numpy vector

[AnsMainak]

Is there a way to directly plot a displacement field (including any auxilary info such as corresponding nodes, dofs) available as a numpy vector(s) in python on the mesh that pymapdl has (eg. after resuming from a db) directly without performing any analysis inside mapdl?

[pmaroneh]

Hi @AnsMainak for this purpose, I would recommend using PyDPF Core. The data can be inserted in a field and this field can be plotted on the mesh.

[akaszynski]

You can also use pyvista for this as well. This works with any numpy arrays.
https://docs.pyvista.org/examples/01-filter/glyphs.html

[AnsMainak]

Thanks for your answers. To clarify, I want the displaced mesh like in mapdl (not just a contour plot of the displacements on the undisplaced mesh). If I'm not wrong, that requires morphing/ warping the mesh in pyvista? Does DPF core have a capability to plot the displaced mesh. Are you aware of examples for either case?

[mikerife]

Hi @AnsMainak There could be several answers here depending on some details of the actual numpy vector. And in addition to using using PyDPF core as @pmaroneh suggested. Do the numpy vector values correspond 1-to-1 to nodes in the MAPDL mesh? If so then we can get the MAPDL mesh as a VTK UnstructuredGrid object, then use PyVista to visualize the numpy vector data. There is an example of this in this PyMAPDL Doc Example:
https://mapdldocs.pyansys.com/examples/00-mapdl-examples/transient_thermal.html#sphx-glr-examples-00-mapdl-examples-transient-thermal-py
Scroll down to the "Visualize a Slice" section. Of course you can visualize the whole model and not just a slice but it shows the general steps. See the PyVista documentation for more information.

If there is not a 1-to-1 correspondence then you could map the numpy displacement field onto the MAPDL mesh...which again can be done then visualized via PyVista.

Mike

[AnsMainak]

Thanks for your reply. I'll check out that example and try to see if I can make it work for my case.

[mikerife]

Hi @AnsMainak PyVista has a "update_coordinates" for the Plotter. Seems like that should work. Sorry I am brand new to PyVista and last time I looked into this I cheated and used the APDL upcoord prior to exporting out the mesh as a VTK UnstructuredGrid object.
Mike

[AnsMainak]

@mikerife Thanks for the suggestion. Will look it up. Thanks!

[mikerife]

Hi @AnsMainak Well, I had forgotten that I had gotten this to work on a simple square plate modal analysis model! Attached is the Jupyter Lab notebook file. Let me know if you have any questions on the example. Mike

ModalAnimation.zip