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Problem with chemical reaction - undefined value found
Posted 6 sept. 2011, 07:46 UTC−4 Heat Transfer & Phase Change, Chemical Reaction Engineering, Studies & Solvers Version 4.2 1 Reply
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Hey everybody,
i have right now a problem with solving a chemical reaction in a tube. I want to check out, how do I have to design a tube to keep the reaction in the tube with cooling water on the outside in a certain frame/range of heat. Right now im designing the reaction with fictitious values for a reaction with extremely coarse mesh.
Now I'm stuck with this error message :
Undefined value found.
- Detail: Undefined value found in the equation residual vector.
There are 11 degrees of freedom giving NaN/Inf in the vector for the variable mod1.c
at coordinates: (0.000431632,0.0145771), (0.000429675,0.014511), (0.000388626,0.0145459), (0.000470642,0.0142859), (0.00047191,0.0142209), ...
It appears by changing in the segregated solver 2 for dependent variables: user defined (values of variables not solved for -> solution - solver 1) to step 1 stationary.
Are the values to close to zero or might there a BC be missing?
I would be very happy to recieve some clues...
Thanx in advance
Simon Erbach
i have right now a problem with solving a chemical reaction in a tube. I want to check out, how do I have to design a tube to keep the reaction in the tube with cooling water on the outside in a certain frame/range of heat. Right now im designing the reaction with fictitious values for a reaction with extremely coarse mesh.
Now I'm stuck with this error message :
Undefined value found.
- Detail: Undefined value found in the equation residual vector.
There are 11 degrees of freedom giving NaN/Inf in the vector for the variable mod1.c
at coordinates: (0.000431632,0.0145771), (0.000429675,0.014511), (0.000388626,0.0145459), (0.000470642,0.0142859), (0.00047191,0.0142209), ...
It appears by changing in the segregated solver 2 for dependent variables: user defined (values of variables not solved for -> solution - solver 1) to step 1 stationary.
Are the values to close to zero or might there a BC be missing?
I would be very happy to recieve some clues...
Thanx in advance
Simon Erbach
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1 Reply Last Post 13 sept. 2011, 07:20 UTC−4
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Posted:
1 decade ago
The solution was kind of simple... Just needed lower Ea (Activating Energy) and deltaH and it worked...