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FSI - Not converging

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I am trying to simulate a free particle movement in microchannel. The particle moves upto a certain point and stops. I get the error "May have reached singularity or Maximum number of Newton iterations reached and Last time-step not convereged" And it runs only for about 0.8 secs while the total time I defined is greater than that (3secs)

I plotted solid stress, displacement, fluid velocity and pressure. Animation for stress shows particle outside the channel at the end of time while in the other three, particle doesn't go till the end of the channel. Outlet is defined in laminar flow.

Please find my model attached.

I am using 5.4. Is this an issue with meshing or solver? Any input is appreciated.


0 Replies Last Post Aug 23, 2020, 8:20 PM EDT
COMSOL Moderator

Hello Praneetha Pulyala

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