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Viscous flow boundary question

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Hello,

I am trying to simulate a region of a deforming viscous solid (ie the lithosphere of Venus). I would like to specify the equivalent of a horizontal strain boundary condition - with the horizontal velocity fixed and the vertical velocity free. Any suggestions? I am using the standard Laminar Flow physics.

Thanks,

Phil

3 Replies Last Post Feb 23, 2011, 1:54 a.m. EST
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Feb 21, 2011, 1:39 a.m. EST
Hi

I would study the underlaying COMSOL equations of noslip, and moving wall BC's (and perhaps some of the others) I believe you will find your need therein, if not by tweaking these somewhat

--
Good luck
Ivar
Hi I would study the underlaying COMSOL equations of noslip, and moving wall BC's (and perhaps some of the others) I believe you will find your need therein, if not by tweaking these somewhat -- Good luck Ivar

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Posted: 1 decade ago Feb 22, 2011, 8:48 p.m. EST
Thanks for the suggestion Ivar,

I think I see what I need in the slip wall BC. The default sets the normal velocity to zero while leaving the tangential free. I can adjust the normal to a fixed velocity as in the moving wall.

Can anyone lead me toward resources that will instruct me on how to create a user-defined boundary condition? Can this be done within the COMSOL GUI?

Phil
Thanks for the suggestion Ivar, I think I see what I need in the slip wall BC. The default sets the normal velocity to zero while leaving the tangential free. I can adjust the normal to a fixed velocity as in the moving wall. Can anyone lead me toward resources that will instruct me on how to create a user-defined boundary condition? Can this be done within the COMSOL GUI? Phil

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Feb 23, 2011, 1:54 a.m. EST
Hi

study the existing BC and add weak contributions at will
You might need to turn on the Main Physics Node - Advanced Settings - Show all model inputs

--
Good luck
Ivar
Hi study the existing BC and add weak contributions at will You might need to turn on the Main Physics Node - Advanced Settings - Show all model inputs -- Good luck Ivar

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