Danckwerts Inflow Boundary Condition
Constraining the composition to fixed values at an inlet to a reactor may sometimes result in issues with unreasonably high reaction rates or singularities at the inlet boundary. These problems may many times be mitigated by using a flux boundary condition instead, based on the inlet concentrations and the fluid velocity. In chemical engineering this type of flux boundary condition is also known as a Danckwerts condition.
Use the Danckwerts condition to specify inlet concentrations to domains where high reaction rates are anticipated in the vicinity to the inlet (
Ref. 2
).
Given an inlet concentration
c
i
,
0
the Danckwerts inflow boundary condition reads
n
⋅
N
i
=
n
⋅
(
u
c
i
,
0
)
See further:
Inflow
