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[Comsol4] Simple Solid Mechanics model takes ages...
Posted 13.07.2010, 06:20 GMT-4 4 Replies
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Hello,
I started a new, very simple model using the Solid Mechanics Model. It? composed of a rectangle with a fixed boundary, and the opposite boundary has an initial displacement. I want to study the relaxation behavior.
I started with a material equal to silicon. After a while I changed it to Aluminium. But, whereas it works great with the silicon (15 seconds max on my pc) , when I change to aluminium it doesn't seem to solve the problem. The progress reads "Time-dependent solver (BDF) 0%" for ages. The time step increae by really small values, and never reach the end.
I attached one of my files. Change the material to aluminium to get the problem.
I started a new, very simple model using the Solid Mechanics Model. It? composed of a rectangle with a fixed boundary, and the opposite boundary has an initial displacement. I want to study the relaxation behavior.
I started with a material equal to silicon. After a while I changed it to Aluminium. But, whereas it works great with the silicon (15 seconds max on my pc) , when I change to aluminium it doesn't seem to solve the problem. The progress reads "Time-dependent solver (BDF) 0%" for ages. The time step increae by really small values, and never reach the end.
I attached one of my files. Change the material to aluminium to get the problem.
Attachments:
4 Replies Last Post 14.07.2010, 11:29 GMT-4
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Posted:
1 decade ago
I have tested with Aluminum your model, and it work properly, solution takes almost few seconds. I don't know if I have made right simulation.
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Posted:
1 decade ago
Ok, thank you for your reply. It works better with your Aluminium. But how where did you take its parameters from. In my version 4.0937 I used the built-in material called Aluminium, with presaved values (rho=2700, E=70e9, nu=0.33).
Your aluminium is called 'Aluminium [solid,bulk]' and I couldn't figure out how you choose it.
However I cannot solve the problem for a time greater than 0.54 seconds. The convergence (progress window) is up to 10? . Does that depend on my computer ( I tried a second time to be sure, and the computation was stuck at 0.52)? How can I get rid of that limitation?
Another question : when I want to stop the computation, it tries to finish the current step, and thus never gives back control to the user. Is it normal?
Your aluminium is called 'Aluminium [solid,bulk]' and I couldn't figure out how you choose it.
However I cannot solve the problem for a time greater than 0.54 seconds. The convergence (progress window) is up to 10? . Does that depend on my computer ( I tried a second time to be sure, and the computation was stuck at 0.52)? How can I get rid of that limitation?
Another question : when I want to stop the computation, it tries to finish the current step, and thus never gives back control to the user. Is it normal?
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Posted:
1 decade ago
I just tried on another computer (laptop, ubuntu 9, Comsol 9.0.0.925), and the calculation seems stuck at time 0.44.
So, two different computers, two different versions, and still no computations that ends. Where can it come from? Is there anything I could do to improve the model ?
(by the way, is there a ' modeling guide' for Comsol 4
.... and it works on our Cluster....
-> Does that simple model requires such good hardware to be solved?
So, two different computers, two different versions, and still no computations that ends. Where can it come from? Is there anything I could do to improve the model ?
(by the way, is there a ' modeling guide' for Comsol 4
.... and it works on our Cluster....
-> Does that simple model requires such good hardware to be solved?
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Posted:
1 decade ago
The material that I used is in Material Library->Elements->Aluminum (I don't know if the parameter are right for your simulation or not). With Aluminum in the Built-in Material the simulation takes more time, I don't have finished it, I closed Comsol before.
The same situation happens if I create a new material with the same constants (the three constants that are used for the simulation) of the Aluminum in the Built-in Material, I think that these constant are not correct for this simulation. It is very strange because the constant in the simulation with Material Library->Elements->Aluminum are the same!
The same situation happens if I create a new material with the same constants (the three constants that are used for the simulation) of the Aluminum in the Built-in Material, I think that these constant are not correct for this simulation. It is very strange because the constant in the simulation with Material Library->Elements->Aluminum are the same!