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Convergence problem
Posted 2025年4月15日 GMT+8 20:45 3 Replies
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Hello,
I have a Comsol license within the company Framatome. I am currently working on a topic related to the simulation of fluid flow within a test loop section (inlet d = 3mm + rack + 4 titanium steam generator tubes with a diameter of 17mm) and I am encountering a problem with the simulation.
The chosen physics:
Laminar flow (Re = 9 / Velocity = 2.36 * 1E-03)
Steady-state study (solver, tolerance, error; all left as default)
Mesh: Normal (Defined by the physics)
Temperature: 25°C
However, in the end, the solution does not converge, displaying the following message: "Failed to find a solution. Divergence in the iterations of the linear solver. The linear solver/preconditioner is ill-conditioned. The relative residual is more than 1000 times larger than the tolerance. The returned solution did not converge properly."
I would greatly appreciate any clarification regarding this type of error and a possible solution.
Best regards,
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It is almost always impossible to make suggestions without seeing the (reduced) mph file.
However 3D laminar flow problems usually require a pressure point constraint for convergence.
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Hello David , Thank u in advance for the reply Conserving all the paramaters that i published before this is the mph file (geometry ) Notice the version is little bit old 4.4
Attachments:
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4.4 is very old and it is unlikely that anyone can open a file.
By the way .mphbin is not a reduced file, see the instructions at the bottom of this page.