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it doesn't work depends on thickness of electrolyte
Posted 2011年5月19日 GMT-4 14:32 Chemical Reaction Engineering, Geometry, Studies & Solvers Version 4.1 3 Replies
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I am trying to make the modelling to predict potential distribution under the thin electrolyte. My model consists of 2 electrodes covered with thin electrolyte.
When the thickness of electrolyte was 1mm, computation was successful and I obtained reasonable result. But, when the thickness is thin (0.02mm), it doesn't work. Boundary conditions are totally same. Only difference between them is thickness of electrolyte. I don't know what problem this model has.
I would appreciate if someone gives me some advice about it. I attached 2 files above 2 examples.
Attachments:
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In the case of 0.02mm thickness your layer has only one mesh element across the layer. This is not enough. To obtain convergence you should increase the number of these elements .
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Thank you for your comment.
I tried to make fine mesh not to across the thin layer and calculate again. But it still has problem.
Error message said,
Feature:Time Dependent solver1 (Sol1/t1)
Error:Nonlinear solver did not converge.
I attached file which mesh was made finer in the domain (thin electrolyte).
I would appreciate if someone tell me what this problem is.
Thank you,
Attachments:
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You should change these things to get the model to converge:
(1) used mapped mesh for electrolyte domain with several elements through the thickness (perpendicular to surface of electrodes) and good density of nodes also in the horizontal (x direction);
(2) under Time-Dependent Solver > Fully Coupled, change Nonlinear method from Constant (Newton) to Automatic (Newton).
-DW