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Stationary study fails, but time-dependent study completes

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When running a stationary study, I receive an error:

Feature: Stationary Solver Failed to find a solution. Singular matrix.

However, when running a time-dependent study, I do not receive any errors and the study finishes.

What could be causing the stationary study to fail in this situation? My model involves a solid block with wells and fractures inside. It couples Solid Mechanics and Darcy's Law with the Poroelasticity interface.

Thank you.


2 Replies Last Post 2022年11月10日 GMT-5 13:55
Henrik Sönnerlind COMSOL Employee

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Posted: 2 years ago 2022年11月10日 GMT-5 02:18

Chances are large that you have too few constraints, so that there are possible rigid body modes. Then a dynamic analysis will run, since the inertial forces will ensure a force balance.

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Henrik Sönnerlind
COMSOL
Chances are large that you have too few constraints, so that there are possible rigid body modes. Then a dynamic analysis will run, since the inertial forces will ensure a force balance.

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Posted: 2 years ago 2022年11月10日 GMT-5 13:55

Thank you, Henrik Sonnerlind! I solved the issue. My matrix permeability was set to 0 m^2 and I solved it by making it a very small value instead, 1e-100.

Thank you for your response!

Thank you, Henrik Sonnerlind! I solved the issue. My matrix permeability was set to 0 m^2 and I solved it by making it a very small value instead, 1e-100. Thank you for your response!

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