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Mass balance problem with "mixture model"
Posted 10 gen 2022, 06:22 GMT-5 Fluid & Heat, General, Computational Fluid Dynamics (CFD) Version 5.6 0 Replies
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Dear all,
i am trying to model nanoparticles in a fluid flow, for the beginning in simple water. Therefore i like to use the mixture model, so i have a dispersed phase (nanoparticles) and a continous phase (water). My model is a quite simple straight tube.
After running the simulation i saw that the volume fraction of the dispersed phase drops to negative numbers in wall regions, however i fixed it with a lower limit in the segregated solver setting.
So after that i checked the mass balance (see derived values). For the continous phase its all fine but for the dispersed phase there are 6% more mass going out than in. I nearly tried everything, mesh studies, tolerance studies of the solver, weak constraints... i couldnt fix the error to an acceptable value.
Maybe the reason is that the volume fraction of the dispersed phase is in maximum regions of magnitude 1e-3.
My file is attached.
I would be so happy if anyone could solve this problem or help.
Best regards Manuel
Attachments:
Hello Manuel Wolfschwenger
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