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Defining steady solution as initial condition.
Posted Mar 3, 2012, 8:57 p.m. EST Version 4.2 2 Replies
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Hi,
I want to define steady solution as initial condition
Therfore, I added two study mode, 1 for steay and 2 for transient.
I solved steady state solution first, and then typed T in the initial values field.
Then, I solved study 2 for transient.
But I had an error,
"Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
There are 14961 equations giving NaN/Inf in the matrix rows for the variable mod1.T
at coordinates: (0.224,0.038), (0.224,0.035), (0,0.038), (0,0.035), (0.224,0.0378125), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns"
Please help.
Thanks.
I want to define steady solution as initial condition
Therfore, I added two study mode, 1 for steay and 2 for transient.
I solved steady state solution first, and then typed T in the initial values field.
Then, I solved study 2 for transient.
But I had an error,
"Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
There are 14961 equations giving NaN/Inf in the matrix rows for the variable mod1.T
at coordinates: (0.224,0.038), (0.224,0.035), (0,0.038), (0,0.035), (0.224,0.0378125), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns"
Please help.
Thanks.
2 Replies Last Post Mar 4, 2012, 4:59 a.m. EST
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Posted:
1 decade ago
Hi
Normally when you link two studies, you use the solver derived values sub-node to select which initial conditions to use, here you can choose betwen the results from previous solver sequence (default when you add multiple solver nodes under thesame study), or the one you defined in the initila conditions.
But in multiphysics multi solver onemust ensure that all BC are defined for all physics, and typically "t" is not defined in a steady state solution while it becomes defined for the transient one, and often one link t into BC's. Ths can lead to errors. It might be your case.
My way for the "t" time issue is t add t=0[s] in the Global Paramter list or whatever other value that is of interest
--
Good luck
Ivar
Normally when you link two studies, you use the solver derived values sub-node to select which initial conditions to use, here you can choose betwen the results from previous solver sequence (default when you add multiple solver nodes under thesame study), or the one you defined in the initila conditions.
But in multiphysics multi solver onemust ensure that all BC are defined for all physics, and typically "t" is not defined in a steady state solution while it becomes defined for the transient one, and often one link t into BC's. Ths can lead to errors. It might be your case.
My way for the "t" time issue is t add t=0[s] in the Global Paramter list or whatever other value that is of interest
--
Good luck
Ivar
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Posted:
1 decade ago
Thanks, IVar
It works!
It works!