Scaling
Because there can be a large variation in mass fraction of the components of a plasma, a logarithmic scaling of the equations is sometimes necessary. So, starting with the equation for a generalized mass transport template
(5-19)
and letting
W
k
=
ln
w
k
,
Equation 5-19
becomes
The first term on the right-hand side depends on which formulation is used. For the Mixture averaged diffusion model:
and for the
Fick’s law
diffusion model:
.
You can switch between the standard and logarithmic formulations of the mass balance equation. In this module the default implementation is logarithmic.
.