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How to include anisotropy in the solid mechanics module

John R Puentes
I am working on a model, simulating an anisotropic material that shrinks and warps due to changes in temperature. I wonder how can I include an initial temperature (thermal strain) in the structural mechanics module? Do I need to use the structure-heat transfer coupling? Is there any way that I can add a constant temperature as the load in the structural mechanics module?


Thanks

3 Replies Last Post Jan 14, 2013, 10:29 AM EST
Nagi Elabbasi Certified Consultant
Posted: 5 years ago Jan 10, 2013, 3:57 PM EST
Hi John,

If the temperature is constant it is simpler to not use the heat transfer physics. You can account for the thermal strains using the “Thermal Expansion” sub-node under elastic materials or using the “Initial Stress and Strain” sub-node and manually setting initial strain equal to CTE*(T-T_Ref).

Nagi Elabbasi
Veryst Engineering
Hi John, If the temperature is constant it is simpler to not use the heat transfer physics. You can account for the thermal strains using the “Thermal Expansion” sub-node under elastic materials or using the “Initial Stress and Strain” sub-node and manually setting initial strain equal to CTE*(T-T_Ref). Nagi Elabbasi Veryst Engineering

John R Puentes
Posted: 5 years ago Jan 14, 2013, 10:04 AM EST
Thanks Nagi,

I have one more question regarding anisotropy, how does COMSOL treat the local and global coordinates in anisotropic models? In anisotropic models is important to be able to impose different local coordinates depending on the orientation of the fibers. Does COMSOL have options for local coordinates in curves and irregular shapes? Where can I find more information about the use of local and global coordinates in anisotropic models?


Thanks
Thanks Nagi, I have one more question regarding anisotropy, how does COMSOL treat the local and global coordinates in anisotropic models? In anisotropic models is important to be able to impose different local coordinates depending on the orientation of the fibers. Does COMSOL have options for local coordinates in curves and irregular shapes? Where can I find more information about the use of local and global coordinates in anisotropic models? Thanks

Nagi Elabbasi Certified Consultant
Posted: 5 years ago Jan 14, 2013, 10:29 AM EST
For curved geometries you can setup a Base Vector System in the Definitions node and refer to it in the Coordinate System Selection of the material model you are using. The manuals contain some examples.

Nagi Elabbasi
Veryst Engineering
For curved geometries you can setup a Base Vector System in the Definitions node and refer to it in the Coordinate System Selection of the material model you are using. The manuals contain some examples. Nagi Elabbasi Veryst Engineering

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