This model is very similar to the incompressible material model:
w = £ a jei( if+if+ifo – 3+£ «I (yi _ f),
‘ =1 1 1 ’
where the initial shear modulus has the form:
and module Ko:
N (1 ^ jo = 53 3 + A) .
Ogden’s models are mainly used for modelling foams of deformations above 700 %.
This equation has the form:
+ D I 2
where U is the potential energy of strains per unit volume, A,,, and
D temperature-dependent material parameters,
І1 = h1 + k2 + h2, (8.28)
J total volume coefficient,
Jel elasticity volume coefficient and k physical elongation.
The initial shear modulus [io in relation to ^ is expressed by the equation:
Most often, the coefficient k„, takes the value 7, for which ko = 1.0125, and the initial value of the module ko is