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How to get the reaction rate of each cell when using Lagrangian – Composition PDF transport method

    • Yee_CFD
      Subscriber

      Hi,


      I am using the composition PDF transport method in the Species transport Manuel to simulate a turbulent reactive flow. I set up an Elementary reaction: A + B = C, and the reaction rate k  should be 1e5 * C[A] * C. Activation energy is 0 with the Pre-exponential factor of 1e5.


      I have two questions:


      1. When the Eulerian - composition PDF transport method is used, I can see the kinetic reaction rate in the contour. How is it calculated? I checked, it not 1e5 * C[A] * C. Of course, I know it should't be 1e5 * C[A] * C because the PDF method is used. But how the reaction rate value calculated in the coutour?


      2. A more important question: When the Lagrangian - composition PDF transport method is used, I can not see the reaction rate of each cell. How can I see the reaction rate of each cell?


      Please help. Thank you for any kind of input!!

    • Yee_CFD
      Subscriber
      Anyboday can help, please?n
    • wcao
      Ansys Employee
      Hi,nHere are some information for your questions:nthe PDF composition is used for turbulent combustion so that the reaction rate is not simply calculated by Arrhenius law. Since multiple PDF transport equations are solved, the reported reaction rate is actually the sum up over the reaction rate calculated in different moments:https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v202/en/flu_th/x1-42100012.5.html; https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v202/en/flu_th/x1-42400012.8.html;nWhen in Lagrangian approach, the reaction is calculated on the particles instead of in the cell so that there is no explicit expression for the reaction rate.nThank you.
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