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Can the integration value be considered to be zero?
Posted 11 mars 2020, 10:02 UTC−4 General, Modeling Tools & Definitions, Equation-Based Modeling Version 5.5 2 Replies
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Hello,
I am taking an integration on the boundary between two physics. I take the integral of the difference between two variables and expect the resulting integral to be zero. However, the integration gives something of the order of 1e2, whereas the variables are of the order of 1e5. My question is: can the integration be considered to be zero in this case?
Thanks,
Alex
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Maybe. I don't think it is possible to give a reliable answer to your question without more information about your model, mesh, the physics being modeled, etc. I suggest that you post your model to the forum so that others may look at it and offer suggestions.
Alternatively, use a much finer mesh, and/or higher-order elements, and re-run your model. If the integrated value that you are talking about gets much closer to zero, then it may indeed be simply a result of numerical error.
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Indeed, I realize that I haven't given much information, but I did use a finer mesh and higher order elements and the integration approaches zero. Also, I noticed that the integration is greater in areas where the dependent variable varies more, so I think it is due to numerical errors.
Thank you,
Alex