As per the information you've provided, I am interpreting it correctly, You came up with a mathematical model for the problem and solved it using the PyAnsys Math module you get the eigenvalues or the frequencies for the modal analysis?
And you want to perform a Modal analysis in Ansys Workbench for the custom material/ conditions you've used in the PyMath case?
So the "Modal Analysis" analysis system in the workbench can be helpful in addressing the concern. For that, you need geometry, material properties, and boundary conditions.
Please find the following video which demonstrates the Modal Analysis using Ansys Workbench.
Modal Analysis in Ansys Mechanical | Ansys Courses
How to create a new material in Ansys- 1. Create Material - ANSYS Innovation Courses
Creating a New Material (ansys.com)
Hope this helps!
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