Inventor Professional 2017 - Stress Analysis FEM Details

[Anonymous]

Hi,

I'm comparing Inventor's Stress Analysis to Strand7 for both my employer and a university major project (undergraduate 4th year CAE course). We currently use Strand for all our FEA, and would like to make use of Inventor's FEA capability where possible.

I'm trying to understand in detail how the Inventor FEA package works and what its limitations are. I've done a lot of reading and experimentation but am still unclear on the following:

• What exact elements/element formulations does Inventor use? Are they isoparametric elements?
• Do the P-refinements add nodes to the mesh/elements (ie. does it go: Tet4, Tet10, Tet20, ... as the order increases)?
• Does it do local P refinement, or only global?
• What does the 'Create Curved Elements' check box really do? (I note that it affects the number of initial p-refinements).
• How does Inventor decide whether to do a h-refinement or a p-refinement step?
• What stresses are displayed (and how are they averaged)? PS. It would be nice to be able to view un-averaged results.
• Is it possible to view the full thickness representation of a plate model?
• Do the 1st and 3rd principal stress plots correspond to the top and bottom surface stresses for a plate model?

Thanks in advance,

Oliver Couch

[johnsonshiue]

Hi Oliver,

I am not an expert in Stress Analysis. I only know very basic stuff. Below is a link to an article talking about the analysis accuracy. You may be able to find answers to some of your questions.

https://knowledge.autodesk.com/support/inventor-products/learn-explore/caas/sfdcarticles/sfdcarticle...

I took a look at Strand7's website. It indicates that Strand7 is capable of non-linear static analysis. Inventor Stress Analysis can only support linear static analysis. However, Inventor FEA is 64-bit and multi-threaded/multi-core enabled. It can handle linear static analysis for complex parts and assemblies. For non-linear static analysis, you will need to use NASTRAN In-CAD add-in to Inventor. This is included as part of the Product Design and Manufacturing Collection along with Inventor Professional.

Many thanks!

[TheCADWhisperer]

Most of your questions are answered in >>this book<<.