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Segregated group X1 Undefined value found.

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Hello,

I am simulating a turbulent pipe flow of pulp... I am interested in a section of 4m and with a entrance section of 4m the simulations doing well, but the turbulence is not developed. I change the entrance section to 5m and I get the message:
"Segregated group X1

Undefined value found.

Exception:
com.femlab.jni.FlNativeException: Undefined value found Solvermodel
Messages:
Undefined value found Solvermodel

Segregated group X1


Stack trace:
at solvermodel.cpp, row 1837, (Undefined value found in the stiffness matrix.
There are 1004 equations giving NaN/Inf in the matrix rows for the variable p
at coordinates: (0,8.01188), (0,8.02687), (0.00892227,8.01959), (0.0176751,8.0122), (0,8.04186), ...
There are 3854 equations giving NaN/Inf in the matrix rows for the variable u
at coordinates: (0,8.01188), (0,8.01937), (0.00446113,8.01574), (0,8.02687), (0,8.03437), ...
There are 3854 equations giving NaN/Inf in the matrix rows for the variable v
at coordinates: (0,8.01188), (0,8.01937), (0.00446113,8.01574), (0,8.02687), (0,8.03437), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns
)
at segregsolver.cpp, row 990, ()
at com.femlab.solver.FlSolver.femStatic(Native Method)
at com.femlab.solver.FemStatic.run(Unknown Source)
at com.femlab.server.FlRunner.run(Unknown Source)
at com.femlab.util.i.run(Unknown Source)
at com.femlab.util.aa.run(Unknown Source)
"

I don't know why this happens.
Someone can help me?

Carla


1 Reply Last Post 29 nov. 2011, 01:52 UTC−5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 29 nov. 2011, 01:52 UTC−5
Hi

I see those error mostly when I have missed a BC conditions, or not defined enough to get an unique solution

--
Good luck
Ivar
Hi I see those error mostly when I have missed a BC conditions, or not defined enough to get an unique solution -- Good luck Ivar

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