Convective Term Formulation
When modeling mass transport in the Nernst–Planck Equations interface, two formulations are available for the convective term: a conservative and a nonconservative formulation.
Equation 3-108
shows the conservative formulation.
In the nonconservative formulation the velocity is moved out of the divergence operator, which improves the stability of systems coupled to a momentum balance (fluid-flow equation). This is only applicable to systems that contain incompressible fluids. In these fluids, the following continuity equation is satisfied:
(3-113)
and
Equation 3-108
can be rewritten as:
(3-114)
which can be called the nonconservative formulation and is the default formulation in the Nernst–Planck Equations interface.
Specify the equation formulation in the Advanced Settings section of the Nernst–Planck Equations interface.
