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Calculate the normal diffusion flux

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I used the down() operator to calculate the normal diffusion flux on the downside of a boundary, the expression was JBn=down(chds.ndflux_c) (in the Variable node). However, after solved, I found it equal to zero all the time. It was so strange, since the concentration difference didn't equal to zero. Where is wrong with the expression? Model file was attached.


0 Replies Last Post 7 giu 2011, 11:20 GMT-4
COMSOL Moderator

Hello Xiaoyi Yu

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