About neo-hookean

[chen junnan]

Hi all

I am doing a simulation about the aortic dissection.I followed the manual step by step to import the neo-hookean into my model.Now I thinked I completed it.
But I'm still confused, I just know how to turn on the neo-hookean in Elmer, I don't know what the neo-hookean looks like in my model, where to set the parameters? Can I set it to look like the picture1？

best regards
chen junnan

[kevinarden]

I have reviewed the manuals, code, and performed some testing. My conclusion is the neo-hookean model in Elmer is the generalized neo-hookean solid which only requires the bulk modulus and the shear modulus which can be calculated form E and nu.

neo=hookean.png (102.31 KiB) Viewed 1458 times

K and G.png (21.18 KiB) Viewed 1458 times

Last line is the calculation of the bulk modulus and shear modulus given E and Nu.

Many commercial codes implement the generalized polynomial rubber elasticity model when they implement neo-hookean. In order to model hyperelastic material models. These models require require the input of C and K constants to fit the materiel response to test data.