species transport(need urgent help)

sree

Dear all, I am doing project on CFD modeling of gas-sparged solid-liquid systems. I have one doubt on species transport. My problem is effect of inner cylinder rotation and gas sparging on the dissolution of benzoicacid in pure water. I solved the coupled mass, momentum and mass transfer equation in three stages 1) In the first stage, I solved the mass and the momentum equations of liquid phase under steady state conditions 2) In the second stage, I solved the multiphase equations (gas-liquid) with the velocity field obtained from the steady state calculations as the initial condition under unsteady state condition. 3) In the third stage, I solved the mass transfer equation with the velocity fields obtained from the unsteady state solution (in which I solved only mass transfer equation). But I am getting same results (final concentrations of benzoicacid) gas sparging with and without rotation I tried in different models like Multiple Reference Frame model and Single Rreference Rrame model

Please give me the suggestion about the species transport.