Maybe check "Finite Element Analysis. Theory and Application with Ansys" by S. Moaveni. However, most books are either about the general theory of FEM (which is pretty much the same regardless of the software) or about the usage of a particular program. Apart from the books, I definitely recommend the use of software documentation, as it’s usually the best source of information and examples. Chapters discussing theory can be particularly useful for you as they focus on the implementation of FEM in given software.

I’m not sure what you mean by the analysis involving 2D and 3D elements. Are you talking about the connection of shell and solid elements ? In FEA, 2D can be understood in two ways - as modeling space (XY in 2D, XYZ in 3D) or as element geometry. You can’t directly switch from 2D to 3D modeling space but you can easily use 2D and 3D elements (shells and solids) in the same analysis.

Try this chapter from Prof. Allen Bower's book. If you want an even simpler introduction, this lecture by Prof. Scott Hollister is a breezy read. COMSOL has a very nice blog as well.

However, these are high-level introductory notes/blogs. As noted above, documentation for ANSYS will always be your best resource.

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Lot of books to choose from. For ANSYS-The Finite Element Method and Applications in Engineering Using Ansys by Erdogan Madenci and Ibrahim Guven is also good book with some elementary theory of FEM and main focus on how-to in ANSYS APDL.

The book suggested by FEA way - Finite Element Analysis. Theory and Application with Ansys" by S. Moaveni is also good with lot of focus on elementary theory and example and introduction to ANSYS APDL/Workbench.

But if you want to know what software is doing behind the scenes, you should know the basics of FEM and should read the basic FEM book first with its difficult math like - Finite element procedures by K J Bathe.

Also you can search ANSYS APDL theory reference manual for more details for behind the scene calculations in Ansys. ANSYS's New platform/GUI is Workbench but it still uses the APDL solver so the books above will be good reference.

If you want just a flavor of FEA, try - Building Better products with Finite Element Analysis by Adams & Askenazi

It's not a book, but this free course from Cornell is aimed at covering what Ansys does behind the scenes. The level of detail feels similar to a review session prior to a final exam in university, so it glosses over a fair bit, but it's a good introduction/refresher.


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