[cucumber]

Hello,

I'm currently trying to investigate the compression of various gas mixtures in a piston/cylinder arrangement. I have my base simulation setup compressing air. I have also successfully completed the simulation with the predefined Methyl-Alcohol-Air mixture with it set to being an ideal gas, Inviscid and Species Transport (no reaction) parameters.

But I want to use a range of my own gas mixtures. I know how to setup a custom mixture but how do a vary the percentages of two gases in the cylinder, say 20% Hydrogen, 80% CO? I'm not using any inlets so I cannot vary it this way, but can I do it through the initial values in the Solution Initialization or is there a way I can define the gas composition in my custom mixture before hand?

Many Thanks