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Reacting Flows

Reacting Flows

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  3. Can you clarify the units of reaction rates in the porous zone when determined via define_vr_rate? It is kmol/m^3 s according to the define_vr_rate documentation. In a porous zone, is the m^3 referring to the total volume, the volume of voids, or the volume of solids?

Can you clarify the units of reaction rates in the porous zone when determined via define_vr_rate? It is kmol/m^3 s according to the define_vr_rate documentation. In a porous zone, is the m^3 referring to the total volume, the volume of voids, or the volume of solids?

Tagged: 19, fluent, fluid-dynamics, Scripting/Journaling/UDF, Species/Reactions
    • January 25, 2023 at 7:17 am
      FAQFAQ
      Participant

      It is kmol/sec/m^3. where the m3 express the gas volume only. Fluent take this value for the UDF and multiply it by the porosity which is (gas volume/total) volume so it ends up in the transport eqn as kmol/sec/m3(total volume). In other words, if you are using it in UDF then in your UDF you need to supply it as per gas volume only.

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