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I am getting following error

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I have used the library model in microfluidics area with laminar flow level set application mode.
original example is made in Axial symmetry 2d space and i have made the geometry in simple 2D plane
Rest everything is kept same.
But it gives me the following error



Exception:
com.femlab.jni.FlNativeException: Expression could not be evaluated
Messages:
Expression could not be evaluated

Stack trace:
at solvermodel.cpp, row 1386, ()
at com.femlab.solver.FlSolver.femTime(Native Method)
at com.femlab.solver.FemTime.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)

Can somebody help

Regards

Chattarbir Singh


1 Reply Last Post 6 feb 2010, 06:19 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 6 feb 2010, 06:19 GMT-5
Hi

in the part of your message the expression name not evaluated is not mentionned, it could be further up or down in the error log.

One cause is if you use library material data that depend on "T" and "p" (or other variables) and you do not solve for these, you must nevertheless define them, in this case adding a constant

T=20[degC]
p=1[atm]

generally helps

Other times it's the initial values left at "0" for T and p if solved for that causes some surprises.

I do not have access to my COMSOL licence these days so I cannot check your model.

Good luck
Ivar
Hi in the part of your message the expression name not evaluated is not mentionned, it could be further up or down in the error log. One cause is if you use library material data that depend on "T" and "p" (or other variables) and you do not solve for these, you must nevertheless define them, in this case adding a constant T=20[degC] p=1[atm] generally helps Other times it's the initial values left at "0" for T and p if solved for that causes some surprises. I do not have access to my COMSOL licence these days so I cannot check your model. Good luck Ivar

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