The polynomial hyperelastic material model is a phenomenological model of rubber elasticity. In this model, the strain energy density function is of the form of a polynomial in the two invariants I 1 , I 2 {\displaystyle I_{1},I_{2}} of the left Cauchy-Green deformation tensor. The strain energy density function for the polynomial model is
W = ∑ i , j = 0 n C i j ( I 1 − 3 ) i ( I 2 − 3 ) j {\displaystyle W=\sum _{i,j=0}^{n}C_{ij}(I_{1}-3)^{i}(I_{2}-3)^{j}}
where C i j {\displaystyle C_{ij}} are material constants and C 00 = 0 {\displaystyle C_{00}=0} . For compressible materials, a dependence of volume is added
W = ∑ i , j = 0 n C i j ( I ¯ 1 − 3 ) i ( I ¯ 2 − 3 ) j + ∑ k = 1 m 1 D k ( J − 1 ) 2 k {\displaystyle W=\sum _{i,j=0}^{n}C_{ij}({\bar {I}}_{1}-3)^{i}({\bar {I}}_{2}-3)^{j}+\sum _{k=1}^{m}{\frac {1}{D_{k}}}(J-1)^{2k}}
where
… excerpt ends here. Continue reading the full article.
