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Expanding Volume within a Constant Volume

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Hello,

I'd like to know if it's possible to create a balloon model in COMSOL in which there is one inlet but no outlet and the volume expands throughout the simulation. Overall, we are trying to model a balloon (medical device) being filled with a saline solution within a sphere with constant volume. The non-expanding sphere will be representative of a uterus.

What we are looking to find are:

a) The pressure gradient on the balloon model due to the saline solution.
b) The pressure gradient due to the exertion of forces from the inner expanding balloon over time on the outer spherical model's (uterus) wall.

Thanks for your time.

3 Replies Last Post 9 ago 2011, 09:25 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 17 feb 2011, 01:09 GMT-5
Hi

why not ? so long you do not try a "stationary" on a system without equilibrium I do not see what could go wrong.

You should adapt the settings to allow large deformations or hyper elasticity or whatever appropriate material conditions

My only comment use the latest v4 update it much more stable ;)

--
Good luck
Ivar
Hi why not ? so long you do not try a "stationary" on a system without equilibrium I do not see what could go wrong. You should adapt the settings to allow large deformations or hyper elasticity or whatever appropriate material conditions My only comment use the latest v4 update it much more stable ;) -- Good luck Ivar

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Posted: 1 decade ago 25 lug 2011, 15:14 GMT-4
I have a similar problem, but with the bladder. You're able to model the balloon? Did you use the fluid structure interaction module? Or perhaps the laminar flow/solid mechanics/moving mesh?

Thank you so much!

Dario
I have a similar problem, but with the bladder. You're able to model the balloon? Did you use the fluid structure interaction module? Or perhaps the laminar flow/solid mechanics/moving mesh? Thank you so much! Dario

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Posted: 1 decade ago 9 ago 2011, 09:25 GMT-4
Dario,

In my experience with COMSOL, I think you will be able to model the expansion of the balloon. all you have to do is constrain your 3D model by holding it in one point so that the other portions of your geometry will have the freedom to move. That's what i did in my 3D simulation with the swelling of rice grain. i used diffusion and structural mechanics.

Jonathan
Dario, In my experience with COMSOL, I think you will be able to model the expansion of the balloon. all you have to do is constrain your 3D model by holding it in one point so that the other portions of your geometry will have the freedom to move. That's what i did in my 3D simulation with the swelling of rice grain. i used diffusion and structural mechanics. Jonathan

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