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how to solve this negative eigen value error?

how to solve this negative eigen value error?

RE: how to solve this negative eigen value error?


RE: how to solve this negative eigen value error?

Negative eigenvalues indicate that some instabilities occur in the analysis. In some cases they are related to buckling but here the reason must be different. Most likely there’s a large unphysical (incorrect) deformation causing stability issues. Carefully check deformed shape and warnings related to distorted elements. Mesh of the nozzle looks really bad too.

RE: how to solve this negative eigen value error?

So what can I do? can I give nozzle fine mesh and try. Because in my next step glass should move but it doesnt move. And which contact property is good? i have given surface to surface is it ok?

RE: how to solve this negative eigen value error?

Yes, start from refining mesh of the nozzle. And carefully check all boundary conditions. Contact should be fine. But something probably causes large distortion and it should be visible on the deformed shape plot.

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