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About the error: Undefined value found in the equation residual vector
Posted 19 ago 2011, 11:42 GMT-4 Parameters, Variables, & Functions, Studies & Solvers Version 4.0, Version 4.0a, Version 4.1, Version 4.2 0 Replies
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I am doing a structural modeling and I am getting this error:
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Undefined value found.
- Detail: Undefined value found in the equation residual vector.
There are 628 degrees of freedom giving NaN/Inf in the vector for the variable mod1.solid.pw
at coordinates: (0.452,0), (0.443445,0),...
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Sounds like those points stated in the error are on my boundaries.
My material is hyperelastic and I get the above error after I apply my user-defined strain energy function. When I use incompressible material assumption the above message in invoked, but when I try to see how compressible material behaves I get this error:
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Failed to find a solution.
System matrix is zero.
Returned solution is not converged.
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I have added a few variables, and I believe that my strain energy function should work fine for the entire domain. Also, I am using exactly the same boundary conditions that I used with a built-in strain energy function and I could get correct solution. So I expect that my BC's should work fine with the new function.
I also doubt that my user-defined strain energy function is causing the problem, because when I use a constant value for the strain energy function, I still get exactly the same error.
I changed the initial values for displacement in the Initial Values from zero to another small value, but had no luck to get rid of the error. Manually entering a Scaling factor for the variable mod1.solid.pw did not help either.
I appreciate your help suggesting what the problem can be from.
Jessica
Hello Jessica
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