*MAT_177 (HILL_FOAM)

LS-DYNA Input Interface KeywordDefines a highly compressible foam based on the strain energy function proposed by Hill.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
*MAT_177 or *MAT_HILL_FOAM
mat_ID	${\rho }_i$		N
MU_1	MU_2	MU_3	MU_4	MU_5	MU_6	MU_7	MU_8
ALPHA_1	ALPHA _2	ALPHA _3	ALPHA _4	ALPHA _5	ALPHA _6	ALPHA _7	ALPHA _8
Blank card

Definition

Field	Contents	SI Unit Example
mat_ID	Material identifier. (Integer)
${\rho }_i$	Initial density. (Real)	$\left[\frac{\text{kg}}{{\text{m}}^{\text{3}}}\right]$
N	Compressibility constant. (Real)
MU_1 - MU_8	Material constants. Default = 0 (Real)	$\left[\text{Pa}\right]$
ALPHA_1 - ALPHA_8	Material exponents. (Real)

Comments

1. The keyword maps to /MAT/LAW62 (VISC_HYP).
2. Material uses Hill type of strain energy function.
3. Poisson coefficient calculated from the compressibility constant N/(1+2N).