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Error in residual computation.....
Posted 2010年6月24日 GMT-4 10:54 0 Replies
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I am Sandesh, an undergraduate, aged 20, and am working on a 3D diffusion model, transient analysis in version 3.2.
In my problem, I have to first define my diffusion expression in "Subdomain Expressions".
For example,
when my expression is 4.5E-13*exp(0.071*c), it works fine....
when I modify my expression to 4.5E-13*exp(0.072*c) then also it works fine....
when I further modify it to 4.5E-13*exp(0.0715*c) and solve the problem, I get the error message:
Error in residual computation.
Very ill conditioned preconditioner.
Last time step is not converged.
When I modify it to 4.5E-13*exp(0.0714*c), it works fine...
and for 4.5E-13*exp(0.0716*c) it gives me two warnings, but solves the problem.....
I do not understand how for such small modifications, the results are erroneous....
Could someone please throw some light on this?
I would be very much grateful for some help...
Thank you...
-sandesh
Hello Sandesh Aher
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