Discussion Forum

Hi

I have a question about COMSOL poroelastic model.
I want to model a sponge like material. In my model I want to apply a sinusoidal displacement at the top of a cylinder and to check the fluid flow inside the porous media.
in my model I did like this: I fixed the bottom of the cylinder and set a prescribed displacement boundary condition at the top with the function: 0.003[m]sin(4*pi*t) in Z direction. (0.003 means the amplitude is 20% strain) and the poroucity of my material is 0.8
but when I run the model over time I get strange displacement filed. at the top of cylinder the displacement in Z direction (along the axis) is correct like what I set. but the displacement flied in other parts is much higher which is not logical I guess.

Now my question is that in general with current comsol poroelastic model is it possible to model solid deformation on matrix, like when you want to compress a sponge (of course not to much less that 20% deformation) or no stress strain model is possible with this model and it is just for non deformable porous media.

If is is possible is it also possible to have large deformation in poroelastic model like the one which is possible in solid mechanics model. because I guess 20% should be considered as large deformation.

Thank you