[CFXILMENAU]

Hi, guys.

I am simulating a centrifuge which is full of air. Original oxygen concentration is 21%. My goal is to increase the oxygen concentration at the wall of the centrifuge, theoretically 25% or 26%, cause O2 is heavier than N2. But I don't know how to get the mass fraction of O2 at the wall of the centrifuge. Do I have to write a Expression to post the properties of O2?Do I need to add a monitor point in output control？

I have already done the CFX-Pre with multicomponent O2 and N2 with fixed composition mixture.

Could anyone help me with this problem？

I truly appreciated your help in advance.