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Expanding boundary as a boundary condition (COMSOL 4.3)
Posted Mar 6, 2013, 10:20 p.m. EST Computational Fluid Dynamics (CFD), Modeling Tools & Definitions, Parameters, Variables, & Functions, Studies & Solvers 2 Replies
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I am doing a flow modeling of the pulmonary system.
I want the driving component of my flow to be an expanding boundary outlet, an expanding volume
The inlet would then be a fixed pressure and the outlet be an expanding boundary, or a at a time varying pressure
The resulting pressure difference would then drive the flow.
Is there a way I can set a boundary condition as an expanding volume?
Or maybe the right way to do this is assigning a periodic pressure variation at the outlet and simply fixing the inlet pressure.
I want the driving component of my flow to be an expanding boundary outlet, an expanding volume
The inlet would then be a fixed pressure and the outlet be an expanding boundary, or a at a time varying pressure
The resulting pressure difference would then drive the flow.
Is there a way I can set a boundary condition as an expanding volume?
Or maybe the right way to do this is assigning a periodic pressure variation at the outlet and simply fixing the inlet pressure.
2 Replies Last Post Nov 12, 2013, 4:45 p.m. EST
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Posted:
1 decade ago
Hi
I would say the "easiest" is to define a pressure at the outlet, and have an equation expressing this pressure depending on the net flow out, taking into account your initial volume and the elastic constant of your container. You would need to add a global equation for this "global" pout variable
--
Good luck
Ivar
I would say the "easiest" is to define a pressure at the outlet, and have an equation expressing this pressure depending on the net flow out, taking into account your initial volume and the elastic constant of your container. You would need to add a global equation for this "global" pout variable
--
Good luck
Ivar
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Posted:
1 decade ago
Hello,
Did you ever figure out how to define a global function that calculates the time-integrated volumetric flux across an outlet boundary? I am trying to do the same thing, but can't figure out how to do the time integration of the out flux.
Thanks,
Helge
Did you ever figure out how to define a global function that calculates the time-integrated volumetric flux across an outlet boundary? I am trying to do the same thing, but can't figure out how to do the time integration of the out flux.
Thanks,
Helge