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How can I define an PML in model solids mechanics ?

I need a help !

I'm using a model of a small rectangle onto a large rectangle 2D axisymmetric
to denote of wave propagation
I have to put the PML absorbed wave to not be reflects
But when i put it and i do the compute
I don't see a difference => PML like does not work !
can you help me please ? what do I do?


note:
-> Model Wizard -> 2D axisymmetric -> structural mechanics -> solid mechanics -> temporel
-> Definitions -> PML

I have searched through the documents COMSOL a model that contains a sample of the PML but I have not found.


4 Replies Last Post May 13, 2013, 9:58 AM EDT
Posted: 4 years ago May 13, 2013, 6:16 AM EDT
beware! PMLs are defined only for harmonic analysis. For transient analysis, please use infinite elements (COMSOL version 4.3 and later).

This is not specific to structural mechanics, but also valid for other physics.

More information may be found in Help > Documentation > Search > infinite elements


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www.comsol.fr
beware! PMLs are defined only for harmonic analysis. For transient analysis, please use infinite elements (COMSOL version 4.3 and later). This is not specific to structural mechanics, but also valid for other physics. More information may be found in Help > Documentation > Search > infinite elements -- www.comsol.fr

Posted: 4 years ago May 13, 2013, 6:36 AM EDT
thank you,

But my internship project is "the simulation of wave propagation by finite element method"
can i use Elements infinite in this case?
thank you, But my internship project is "the simulation of wave propagation by finite element method" can i use Elements infinite in this case?

Posted: 4 years ago May 13, 2013, 7:38 AM EDT
Actually, the search for "infinite elements" returns a lot of information, so my first answer was too general. Here is a more specific answer for structural mechanics: please check the chapter "About the Low-Reflecting Boundary Condition" in the MEMS or Structural Mechanics Module documentation.

Please also not that, under some circumstances, a periodic boundary condition might also be helpful. For instance:
www.comsol.com/showroom/gallery/9903/


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www.comsol.fr
Actually, the search for "infinite elements" returns a lot of information, so my first answer was too general. Here is a more specific answer for structural mechanics: please check the chapter "About the Low-Reflecting Boundary Condition" in the MEMS or Structural Mechanics Module documentation. Please also not that, under some circumstances, a periodic boundary condition might also be helpful. For instance: http://www.comsol.com/showroom/gallery/9903/ -- www.comsol.fr

Posted: 4 years ago May 13, 2013, 9:58 AM EDT
thank you
I'll try from this model.
thank you I'll try from this model.

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