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Continous first spatial derivative?
Posted May 18, 2012, 1:43 p.m. EDT Version 4.2a 0 Replies
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I'm trying to model a chemical reactor. In my model I'm using a boundary PDE module, solving a concentration profile in one dimension.
Unfortunately, my solution is behaving very erratically. One of the terms in my model uses the convective coefficient for the forced flow of the fluid. I believe that since the first spatial derivative is not continuous between elements the convective term is causing 'bumps' in my solution. Each iteration makes these bumps worse and they eventually become very significant.
It seems like this would be a pretty common problem. Is there a known solution? I've tried a google search and I've turned up "Argyris elements" which have continuous first derivatives, but when I try them it get an error "Failed to evaluate variable Jacobian" "Variable mod1.CTx". Is there something else I should be trying?
Hello Andrew Prudil
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