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Failed to evaluate variable jacobian - using a step function

Posted Nov 19, 2012, 5:43 a.m. EST Fluid & Heat, Computational Fluid Dynamics (CFD), Modeling Tools & Definitions, Parameters, Variables, & Functions, Studies & Solvers Version 4.3a 1 Reply

Geovani Souza
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Hi every one,

Im trying to put a BC (volumetric flow rate) in my model as a step function. But the following error occur:


Failed to evaluate variable Jacobian.
- Variable: step1
- Geometry: 1
- Point: 2


anyone know how can i solve?


best regards,

Geovani
1 Reply Last Post Nov 19, 2012, 5:58 a.m. EST
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Nov 19, 2012, 5:58 a.m. EST
Hi

you must have defined a value or function that cannot be derived (Dirac function or other). be sure you use a continuous BC expression

--
Good luck
Ivar
Hi you must have defined a value or function that cannot be derived (Dirac function or other). be sure you use a continuous BC expression -- Good luck Ivar

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