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Problem with chemical reaction - undefined value found

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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


1 Reply Last Post 2011年9月13日 GMT-4 07:20

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Posted: 1 decade ago 2011年9月13日 GMT-4 07:20
The solution was kind of simple... Just needed lower Ea (Activating Energy) and deltaH and it worked...
The solution was kind of simple... Just needed lower Ea (Activating Energy) and deltaH and it worked...

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