Reacting Flows

Reacting Flows

What numeric method is used in the Fluent Stiff Chemistry Solver? Is it operator splitting or something else? What is the order of accuracy of the resulting chemistry source term(s)? Is there a difference in the treatment between the Fluent Stiff Chemistry solver and Chemkin CFD solvers?

    • FAQFAQ
      Participant

      Fluent employs no formal operator splitting method. Instead, the chemistry source terms are integrated over a timescale that is assumed to give them step-independence. This timescale is chosen to be larger than the reaction timescale, to allow for stability, but small enough to produce a step-independent source term. For steady runs, the timescale is 1/10 of the minimum computed diffusion/advection timescale; for transient runs the physical timescale is used. This treatment for reaction source terms is first-order accurate.