7.6.17.34.12. Nernst_Planck

Syntax

Species Diffusion [{of} SpeciesName] = Nernst_Planck ([F = f] | [R = r])

Scope

Aria Material

Description

The diffusive flux is

${\bf{J}} = C \left(\frac{v_i S_i F D_i}{R T} \nabla V - D \nabla S_i \right)$

where $v_i$ is the valence of the ion species, $S_i$ the molar concentration, $F$ the provided Faraday’s constant, $D_i$ the SPECIES_DIFFUSIVITY, R the provided gas constant, $T$ the temperature, and $V$ the voltage.

If both POROSITY and TORTUOSITY_FACTOR models are present then $C = \phi\tau$ , else $C=1$ .

Parameter	Value	Default
{of}	{of \| species \| subindex}	–
SpeciesName	string	–
f	real	9.649e+04
r	real	8.314