When defining transport for species c, the general advection-diffusion equation applies:

(19–7)

where and s are the scalar diffusivity coefficient and the source term, respectively. A pure transport equation is obtained when the diffusivity and the source term s are set to zero.

The parameter is either 0 or 1 indicating that advection is disabled or enabled, respectively. If there is no transport, then the velocity field is not necessary.

  Disable advection term