bConverged

*HYPERFOAM

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*HYPERFOAM

Keyword type: model definition, material

This option is used to define a hyperfoam material. There is one optional parameters, N. N determines the order of the strain energy potential. Default is N=1. All constants may be temperature dependent.

The hyperfoam strain energy potential takes the form

$\displaystyle U=\sum_{i=1}^{N} \frac{2 \mu_i}{\alpha_i^2} \left[ \lambda_1^{\al... ...ha_i}+\lambda_3^{\alpha_i}-3+\frac{1}{\beta_i}(J^{-\alpha_i \beta_i}-1) \right]$

(169)

where $\lambda_1$ , $\lambda_2$ and $\lambda_3$ are the principal stretches. The parameters $\beta_i$ are related to the Poisson coefficients $\nu_i$ by:

$\displaystyle \beta_i=\frac{ \nu_i}{1 -2 \nu_i}$

(170)

and

$\displaystyle \nu_i= \frac{ \beta_i}{1+2 \beta_i}.$

(171)

First line:

*HYPERFOAM
Enter parameters and their values, if needed

Following line for N=1:

$\mu_{1}$ .
$\alpha_{1}$ .
$\nu_{1}$ .
Temperature.

Repeat this line if needed to define complete temperature dependence.

Following line for N=2:

$\mu_{1}$ .
$\alpha_{1}$ .
$\mu_{2}$ .
$\alpha_{2}$ .
$\nu_{1}$ .
$\nu_{2}$ .
Temperature.

Repeat this line if needed to define complete temperature dependence.

Following lines, in a pair, for N=3: First line of pair:

$\mu_{1}$ .
$\alpha_{1}$ .
$\mu_{2}$ .
$\alpha_{2}$ .
$\mu_{3}$ .
$\alpha_{3}$ .
$\nu_{1}$ .
$\nu_{2}$ .

Second line of pair:

$\nu_{3}$ .
Temperature.

Repeat this pair if needed to define complete temperature dependence.

Example:

*HYPERFOAM,N=2
0.164861,8.88413,2.302e-5,-4.81798,0.,0.

defines a hyperfoam material with two terms in the series.

Example files: beamhf.

Next: *INCLUDE Up: Input deck format Previous: *HYPERELASTIC Contents

guido dhondt 2011-03-26