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no convergence for cylinder under external pressure

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I have a 2D model of a cylinder tube.
External pressure acts on the outer wall of the cylinder, a different pressure on the inner wall.
The analysis does not converge:

I get an error message:
"Failed to find a solution for the initial parameter./Maximum number of Newton iterations reached./There was an error message from the linear solver./The relative error (3.9e+002) is greater than the relative tolerance./Returned solution is not converged./ - Feature: Stationary Solver 1 (sol1/s1)"

What is missing, to make it converge?
I include a model file.


I got the same problem with a 3D modeling of a cylinder tube, if I put the base on a "Roller" foundation, while it does converge, if I use "fixed constraint".


1 Reply Last Post 12.02.2014, 05:05 GMT-5

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Posted: 1 decade ago 12.02.2014, 05:05 GMT-5
With increasing experience I found the solution for 2-D myself: I need to insert a "fixed constraint" at two "points" or a "roller" on one surface segment.

With increasing experience I found the solution for 2-D myself: I need to insert a "fixed constraint" at two "points" or a "roller" on one surface segment.

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