spheres_and_cylinders

spheres_and_cylinders(network, pore_diameter='pore.diameter', throat_diameter='throat.diameter')

Computes diffusive shape coefficient for conduits assuming pores are spheres and throats are cylinders.

Parameters:

network (OpenPNM Network object)

pore_diameterstr

Name of the dictionary key on network containing the ndarray of pore diameter values.

throat_diameterstr

Name of the dictionary key on network containing the ndarray of throat diameter values.

Returns:

size_factors – Array (Nt by 3) containing conduit values for each element of the pore-throat-pore conduits. The array is formatted as [pore1, throat, pore2].

Return type:

ndarray

Notes

The diffusive size factor is the geometrical part of the pre-factor in Fick’s law:

\[n_A = \frac{A}{L} \Delta C_A = S_{diffusive} D_{AB} \Delta C_A\]

Thus \(S_{diffusive}\) represents the combined effect of the area and length of the conduit, which consists of a throat and 1/2 of the pore on each end.