Mass transfer units in fluent

nite_surfer

Hi all, I hope someone can give me an advice in this topic.

In Fluent's UDF manual it is stated that the units that must be returned in a DEFINE_MASS_TRANSFER UDF are kg/m3.

Commonly mass transfer coefficients are in kg/m3-s so for non-steady simulations it is possible to multiply by the current time step and the units are fullfilled, but in steady state it is not possible.

I have been told that UDF manual is a misprint and that the returned units are always kg/m3-s, but my simulations in steady state gave me too high mass transfer values, while non-steady simulations with the units as asked in the manual, are correct.

Can anybody help me in this?

If it is not a problem with the manual how can I circumvent the units affair in steady state?

Thanks Nite