SimScale CAE Forum

Shaft analysis MUMPS contradictory error

I am trying to complete a dynamic analysis of a rotating shaft that has two links attached. It has meshed well, but I have received a strange error. What’s strange is that my settings are actually what it’s telling me to do or it did not identify my settings. Somewhere it failed because of it:

“The MUMPS linear solver was set up using the matrix type symmetric positive definite, but the actual system matrix has negative or zero terms on its diagonal. This is contradictory. Please switch the Matrix type in the numerics settings to automatic detection.”

In Run 2, it was MUMPS set to “automatic detection”, not “symmetric positive definite”. In Run 3, for fun, it was set to “Multifrontal”, but it still had the same error. Can anyone help with this seemingly erroneous error? Thanks!

“Stanchion Bolt Shaft”

Hey @profjbirt!

Will have a look at that later in the evening. Tagging our experts, the @FEA-SQUAD here in the meantime.



Thank you! I will try a simpler analysis later to get some results.

And my attempts at Static analysis aren’t working either. Something in my model? So frustrating.