[gyf135]

Hi folks,

I am currently modeling the electro-hydrodynamics equation using UDS. Considering that the UDF guide says "advective flux field that is supplied by your UDF should be divergence-free", I am wondering if the "advective flux field" here means the vector field of psi (which has a unit of velocity) or the product of psi and phi(uds).

Since the electric field here is certainly not conserved due to the space charge effect but the current density is a conserved value for a steady-state solution, I am not sure if it is ok to type in the psi as "mobility * electric field and phi(uds) representing the charge density".

Thank you for your help!