Difference between revisions of "Talk:Composite analysis"

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Thanks. It's nice to hear a voice with comments.
 
Thanks. It's nice to hear a voice with comments.
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Hi, I suggest that you use quadratic/second order FE elements for your analysis, they usually give you the best accuracy.
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If the shell in thin (span to thickness ration > 30) and relativelly flat Kirchoff plate element formulation should work fine (no transverse shear deformation) => elements called DKT in Code-Aster.
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If the shell is thicker (span / thickness ration between 15 and 30) but curvature is negligible, the First order Shear Deformation Theory (FSDT) is recommended as it allows for transverse shear deformability => it is the DST FE formulation in Code-Aster (use ~0.8333 as shear correction factor for a better accuracy).
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If the shell is thick and significantly curved, a real 3D shell formulation is required; in Code-Aster, these elements are called Coque3D.
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To see an "old" example of a composite shell analysis, you can have a look at this archive: http://www.caelinux.com/downloads/examples/modal.tar.gz
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Joël Cugnoni

Latest revision as of 14:12, 31 March 2009

130 visitors and 0 contributions

Do you think that this is a good idea (comosite analysis wiki)?

Is this information in other wiki?


Well maybe you should kick it off with an example and others can tune in with improvements

/C


Element size seems reasonable, if the results appears strange later on, it's just a matter of using code_aster to convert it to quadratic elements - but I'm no expert.

Well as you say; units matter, but I would prefer [m] in this case for some reason :)

/C


Thanks. It's nice to hear a voice with comments.


Hi, I suggest that you use quadratic/second order FE elements for your analysis, they usually give you the best accuracy.

If the shell in thin (span to thickness ration > 30) and relativelly flat Kirchoff plate element formulation should work fine (no transverse shear deformation) => elements called DKT in Code-Aster.

If the shell is thicker (span / thickness ration between 15 and 30) but curvature is negligible, the First order Shear Deformation Theory (FSDT) is recommended as it allows for transverse shear deformability => it is the DST FE formulation in Code-Aster (use ~0.8333 as shear correction factor for a better accuracy).

If the shell is thick and significantly curved, a real 3D shell formulation is required; in Code-Aster, these elements are called Coque3D.

To see an "old" example of a composite shell analysis, you can have a look at this archive: http://www.caelinux.com/downloads/examples/modal.tar.gz

Joël Cugnoni