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velocities exceeding critical value N 61

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Old   April 20, 2022, 10:19
Default velocities exceeding critical value N 61
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shuqichang
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Hello,
I always get an error at run time that is faster than N 61. I also tried to change some of the parameters, but nothing worked out. I hope you can help me solve it. Attached are my running file and STL file. Thank you for your help .
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Old   April 22, 2022, 08:44
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Arun Kamath
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Some comments:
You are attempting a 3D simulation with 2D boundary conditions.
control.txt should have C12 and C 13 as 21 C 14 also 21.

ctrl.txt
I 12 1
N 40 3
N 47 0.1

Have you tried refining the grid, say to dx=0.5m?
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Old   April 22, 2022, 09:06
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Quote:
Originally Posted by kamath View Post
Some comments:
You are attempting a 3D simulation with 2D boundary conditions.
control.txt should have C12 and C 13 as 21 C 14 also 21.

ctrl.txt
I 12 1
N 40 3
N 47 0.1

Have you tried refining the grid, say to dx=0.5m?
Hello,
I will make corrections according to your suggestions. But I removed X 24 after I asked the question, and it worked fine without the error of exceeding N 61. I'm not sure if the problem has anything to do with X 24.
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Old   April 22, 2022, 10:07
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That is interesting.
Are you sure then that the X 24 inputs you provide are correct? A wrong input for the moment of inertia can be a problem.

OR
The stl file may have two few triangles for representing the structure. This can be improved using the cad software you used to generate the stl file.
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