*HYPERFOAM

ProductsAbaqus/StandardAbaqus/ExplicitAbaqus/CAE

TypeModel data

LevelModel

Abaqus/CAEProperty module

Optional parameters

MODULI

This parameter is applicable only when the HYPERFOAM option is used in conjunction with the VISCOELASTIC option.

Set MODULI=INSTANTANEOUS to indicate that the hyperfoam material constants define the instantaneous behavior. This parameter value is not available for frequency domain viscoelasticity in an Abaqus/Standard analysis.

Set MODULI=LONG TERM (default) to indicate that the hyperfoam material constants define the long-term behavior.

N

Set this parameter equal to the order of the strain energy potential. The maximum value is N=6. The default is N=1.

POISSON

Set this parameter equal to the effective Poisson's ratio, $ν$ , of the material. This parameter is valid only when the TEST DATA INPUT parameter is specified.

If this parameter is included, it is assumed that $ν_{i} = ν$ for all i and that lateral strain test data and volumetric test data are not required. If this parameter is omitted, the $ν_{i}$ are calculated from lateral strain data and/or volumetric test data.

TEST DATA INPUT

Include this parameter if the $μ_{i}$ , the $α_{i}$ , and the $ν_{i}$ material constants are to be computed by Abaqus from data taken from simple tests on a material specimen. If this parameter is omitted, $μ_{i}$ , $α_{i}$ , and $ν_{i}$ must be given directly on the data lines.

To define elastomeric foam behavior by giving test data

No data lines are used with this option when the TEST DATA INPUT parameter is specified. The data are given instead under the BIAXIAL TEST DATA, the PLANAR TEST DATA, the SIMPLE SHEAR TEST DATA, the UNIAXIAL TEST DATA, and the VOLUMETRIC TEST DATA options.

Data lines to define the elastic properties directly

First line if N=1

$μ_{1}$ .
$α_{1}$ .
$ν_{1}$ .
Temperature.

Repeat this data line as often as necessary to define the material constants as a function of temperature.

First line if N=2

$μ_{1}$ .
$α_{1}$ .
$μ_{2}$ .
$α_{2}$ .
$ν_{1}$ .
$ν_{2}$ .
Temperature.

Repeat this data line as often as necessary to define the material constants as a function of temperature.

First line if N=3

$μ_{1}$ .
$α_{1}$ .
$μ_{2}$ .
$α_{2}$ .
$μ_{3}$ .
$α_{3}$ .
$ν_{1}$ .
$ν_{2}$ .

Second line if N=3

$ν_{3}$ .
Temperature.

Repeat this pair of data lines as often as necessary to define the material constants as a function of temperature.

Data lines for higher values of N (up to 6)

The data lines for higher values of N follow the same pattern. First, give the $μ_{i}$ and $α_{i}$ for i from 1 to N. Then, give the N $ν_{i}$ . Finally, give the temperature. Exactly eight data values should be given on each line.