about Mass Fraction

Jaloha

Hi，everybody, I've got a little question about mass fraction.

I used a variable component material(7 components) as the working fluid in my CFX simulation case(A reactor, including duct connected with it).

After proceeding to CFX-Post, I made a xy-plane as a cross section in the Reactor, and the variable I chose was "NH3 Mass Fraction"(NH3 is one of the 7 components). The plot did display a colour difference on the xy-plane, which indicated a value difference of the "NH3 Mass Fraction".

However, after I exported a .csv file of the value "NH3 Mass Fraction" and opened it in Excel, I found that the values are the same on different points of the plane.

I'm really curious about it. Is it caused by the fluid material type I have set? Since I have separately set the 7 component fractions one by one for the inlet boundary condition and the initialisation.

Regards.