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Help with 'Undefined value found in the stiffness matrix' error!

Posted 7 févr. 2012, 09:14 UTC−5 Materials, Parameters, Variables, & Functions, Studies & Solvers, Structural Mechanics Version 4.2a 1 Reply

James Hickey
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Hi,

I am trying to build a model that first constructs a temperature field, and then uses that temperature in a second study that has a temperature dependent viscoelasticity. The end result I'm hoping for is a time and temperature dependent displacement. I have been using the library model 'viscoelastic_tube' as a guide.

However, when I try and run the second study I get the following error:

Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
• There are 111 equations giving NaN/inf in the matrix rows for the variable mod1.solid.qPHIPHI1
at coordinates...
• There are 111 equations giving NaN/inf in the matrix rows for the variable mod1.solid.qRR1
at coordinates...
• There are 111 equations giving NaN/inf in the matrix rows for the variable mod1.solid.qRZ1
at coordinates...
and similarly for the degrees of freedom, Nan/Inf in the matrix columns.
- Feature: Time Dependent Solver 1(sol2/t1)
- Error: Undefined value found

Any help on this matter would be greatly appreciated.

Thanks in advance,

James.
1 Reply Last Post 16 avr. 2012, 04:03 UTC−4
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Hello James Hickey

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Stefan Hoyer
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Posted: 1 decade ago 16 avr. 2012, 04:03 UTC−4
Hi!

I'm facing the same problem with a Heat Transfer / fluid flow Problem. Did you find the error in the meantime?

Thanks to anyone who can help,

Stefan
Hi! I'm facing the same problem with a Heat Transfer / fluid flow Problem. Did you find the error in the meantime? Thanks to anyone who can help, Stefan

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