MATX62

Format

Example

Definitions

Comments

1. The material identification number must be that of an existing MAT1 Bulk Data Entry. Only one MATXi material extension can be associated with a particular MAT1.
2. MATX62 is only applied in geometric nonlinear analysis subcases which are defined by ANALYSIS = EXPDYN. It is ignored for all other subcases.
3. NU is defined on the corresponding MAT1.
4. If no pair GAM1, T1 is given the law is hyper-elastic.
5. The strain energy density W is computed using the following equation:
   (1)

   $$\text{W}\left({\lambda }_1,{\lambda }_2{\lambda }_3\right)=\sum _{\text{i}=1}^{\text{N}}\frac{2\mu }{{\alpha }_{\text{i}}^2}\left({\lambda }_1^{{\alpha }_{\text{i}}}+{\lambda }_2^{{\alpha }_{\text{i}}}+{\lambda }_3^{{\alpha }_{\text{i}}}-3+\frac{1}{\beta }\left({\text{J}}^{-\alpha \text{i}\beta }-1\right)\right)$$

   with ${\lambda }_i$ being the i^th principal stretch, J = $\lambda$ ₁ * $\lambda$ ₂ * $\lambda$ ₃ being the relative volume and $\beta =\frac{\text{v}}{\left(1-2\text{v}\right)}$ . O < NU < 0.5

   The ground shear modulus is:(2)

   $$\text{G}=\sum _1^{\text{N}}{\mu }_{\text{i}}$$
6. This card is represented as a material in HyperMesh.