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126.96.36.199 Constant Orthotropic Diffusivity
The material type for constant orthotropic diffusivity materials is “diff-const-ortho”. The following material parameters must be defined:
|<free_diff>||free diffusivity of solute (diffusivity in solution)||[L /t]|
|<diff>||diffusivities along orthogonal directions (||[L /t]|
When the permeability is orhotropic, where are orthonormal vectors normal to the planes of symmetry (defined as described in Section 4.1.1↑). For this material model, 's are constant. Therefore this model should be used only when strains are small. Note that the user must specify , since a solute cannot diffuse through the biphasic-solute mixture faster than in free solution.
<diffusivity name="Permeability" type="diff-const-ortho"> <free_diff>0.005</free_diff > <diff>0.002,0.001,0.003</diff> </diffusivity>