How to Set the Gas Fraction for a Multiphase Liquid in SOLIDWORKS FS
 

Hi all.
The task is to calculate a multiphase mixture of water + methane in SOLIDWORKS FS.

1. When adding two media, if liquid is selected by default, you can add the second one, also only liquid, there is also methane, but, as I understand it, it will be in liquid form.
2. If "Free Surface" is turned on, liquid and gas are added, two different media.
I include point 2. Boundary conditions: input - pressure, output - flow.
A substance concentration tab has appeared at the input; by default, water is selected as the liquid. BUT THERE IS NO POSSIBILITY TO INPUT THE VOLUME OF THE FRACTION, as, for example, this happens when you use two liquids at the inlet.
There is no option to enter a faction, only an incomprehensible dependency.

By the way, the total pressure can no longer be set either, but oh well. How to assign a faction? For example, I need 10% methane.
Thank you.