Subscript denoting species A |
A |
Subscript denoting species B |
B |
Klinkenberg parameter (F/L2) |
b |
Moles of gas per unit volume (moles/L3) |
C |
Moles of species i per unit volume (moles/L3) |
Ci |
Effective molecular diffusion coefficient (L2/T) |
D |
Molecular diffusion coefficient (L2/T) |
Dm |
Knudsen diffusion coefficient for species i (L2/T) |
 |
Equimolar flux of species i (moles/L2T) |
Ji |
Intrinsic permeability (L2) |
k |
Permeability to gas or effective gas permeability (L2) |
kg |
Apparent gas permeability (L2) |
kga |
Knudsen number |
Kn |
Coordinate tangent to path of motion (L) |
l |
Ratio MA/MB |
MAB |
Ratio MB/MA |
MBA |
Molecular weight of specie i |
Mi |
Molecular mass of specie i |
mi |
Porosity |
n |
Number of molecules per unit volume (L-3) |
ñ |
Mole flux of species i (moles/L2T) |
Ni |
Mole flux of species i due to diffusion (moles/L2T) |
 |
Diffusive flux for the gas as a whole (non-equimolar flux) (moles/L2T) |
ND |
Mole flux of gas due to viscous flow (moles/L2T) |
Nv |
Mole flux of species i due to advection in viscous flow (moles/L2T) |
 |
Pressure (F/L2) |
p |
Mean pressure (F/L2) |
 |
Partial pressure of species i |
pi |
Ideal gas law constant (FL)/(moles temperature) |
R |
Absolute temperature |
T |
Volume flux (L/T) |
v |
Mean speed of species i molecules (L/T) |
 |
Mole fraction of species i |
xi |
Vertical coordinate (L) |
z |
Volume of gas per unit bulk volume |
θg |
Mean free path length (L) |
λ |
Characteristic pore dimension (L) |
λp |
Molecular diameter (L) |
σ |
Dynamic viscosity (FT/L2) |
μ |
Tortuosity |
τ |