The Mooney-Rivlin strain energy density function is expressed as:
| Mooney-Rivlin Material Constants |
Energy Density Equation |
| Two-constant formulation |
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| Five-constant formulation |
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| Six-constant formulation |
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- JI, J2, and J3 are the reduced invariants of the right Cauchy-Green deformation
tensor and can be expressed in terms of principal stretch ratios
- A, B, C, D, E, and F are the First, Second, Third, Fourth, Fifth, and Sixth
material constants of the Mooney-Rivlin material model. You enter these
constants in the Material properties dialog box.
, = Poisson's ratio
It has to be noted that as the material approach incompressibility, the
third invariant, III, approaches unity, while K approaches infinity. Thus, for values of
Poisson's ratio close to 0.5, the last term in W1 remains bounded, and a solution can be
obtained.
The Mooney-Rivlin material model can be used with solid elements and
thick shells.
The
Mooney-Rivlin
constants are automatically computed when the Use curve data
to compute material constants option in the Material dialog box is selected. The constants are saved in a text file
with the extension .log in the result folder of the active study.