mass transfer by source
 

hai all,

I have one question about setting additional variable mass transfer in CFX5.5.7.1.

in two phase (gas and water), There is a soluble component (A) in gas phase. I want to model the mass transfer of A from gas to water and I set two additional variables for A in each phase

Assuming: source=density*mass transfer coefficient *(saturation mass fraction of A in water- actual mass fraction of A in water), in which saturation mass fraction of A in water can be calculated by Herry's law.these source term gives unit of Kgm^-2s^-1 but when I input this source term in fluid mass source in cfx pre by using subdomain,but it giving error of it is not correct unit and required unit is Kgm^-3s^-1 of source

actualy in source term , i have to include the interfacial area, then only unit will match, but in cfx validate report of bubble column shows,cfx 5 take interfacial area automatically, but i don't know why this error is coming

please help my proplem