II.1.11.2 In-plane and out-of-plane components

As has been done for the motion equations, one assumes a decoupling of in-plane laminate thermal conductivity and out-of-plane conductivity. Therefore, the thermal flux is separated into an in-plane flux:

and the out-of-plane component $q_3$.

Correspondingly, the tensor of thermal conductivity coefficients is separated into an in-plane conductivity tensor:

and the out-of-plane conductivity ${\lambda }_{33}^T$. The “shear” components ${\lambda }_{31}^T$ and ${\lambda }_{23}^T$ are neglected in the homogenization theory. (This means that out-of-plane and in-plane conductivities are decoupled.)