Hi, your first assumption is correct. Chemkin is solving differential equations so that it needs a initial condition. For PSR (perfectly stirred reactor), it will be an ODE so that the initial conditions, including the initial gas species fractions will be necessary. Thanks.

Excuse me. I read the Theory manual for more information after seeing your answer. However, it seems that this manual states that ODE is used in the combustion reaction. But I use plasma reaction. Is it the same for plasma reactions?nI used 'quote' because I don't know how to get the answer. Thank you.n