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Results are also different with each other between old version and new version
Posted Jul 2, 2010, 4:15 a.m. EDT Version 3.5a 1 Reply
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Dear Sir
I have two questions about comsol simulation.
1. I have load a file from "step index fiber" model liblary using comsol old version (comsol version3.4), but the result is different from your standard result originally contains in the liblary without modifying any parameter after re-meshing and run. Would you give me some suggestions?
2.Also, I have load this file from the same liblary using comsol new version (comsol version3.5a), and the result is still different from your standard result originally contains in the liblary after re-meshing and run. BTW., the results are also different with each other between old version and new version. Do you know what happen?
ps.the attach file is the results are different with each other between old version and new version.
Thanks a lot in advance for your help.
Best regards,
Yu-Mei
I have two questions about comsol simulation.
1. I have load a file from "step index fiber" model liblary using comsol old version (comsol version3.4), but the result is different from your standard result originally contains in the liblary without modifying any parameter after re-meshing and run. Would you give me some suggestions?
2.Also, I have load this file from the same liblary using comsol new version (comsol version3.5a), and the result is still different from your standard result originally contains in the liblary after re-meshing and run. BTW., the results are also different with each other between old version and new version. Do you know what happen?
ps.the attach file is the results are different with each other between old version and new version.
Thanks a lot in advance for your help.
Best regards,
Yu-Mei
1 Reply Last Post Jul 2, 2010, 8:02 a.m. EDT
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Posted:
1 decade ago
Hi
I do not fully understand why things are different, apart that it looks like you are not chasing the same mode. In the library file the solution has been calculated and the person who saved it could have saved it with the view of mode N (different from 1) while if you rerun it or even remesh and rerun it, it will by default show you mode "1" the first of the list. So you should first check the mode number to be sure you are looking at the same mode.
2nd between versions there are sometimes subtile differences in precision due to the numerical algorithms used and how these have been enhanced so a few percent difference, for the axactly same input and mesh distribution (difficult to guarantie between version) is for me quite normal. I cannot see exactly how much differences you are getting so I cannot really tell for your case (and I do no linger have any V3.4 up. Support can give you more details for such cases.
Good luck
Ivar
I do not fully understand why things are different, apart that it looks like you are not chasing the same mode. In the library file the solution has been calculated and the person who saved it could have saved it with the view of mode N (different from 1) while if you rerun it or even remesh and rerun it, it will by default show you mode "1" the first of the list. So you should first check the mode number to be sure you are looking at the same mode.
2nd between versions there are sometimes subtile differences in precision due to the numerical algorithms used and how these have been enhanced so a few percent difference, for the axactly same input and mesh distribution (difficult to guarantie between version) is for me quite normal. I cannot see exactly how much differences you are getting so I cannot really tell for your case (and I do no linger have any V3.4 up. Support can give you more details for such cases.
Good luck
Ivar