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  3. create nonlinear BC in Fluent dynamic

create nonlinear BC in Fluent dynamic

    • December 11, 2019 at 8:31 am
      Hoosein86
      Subscriber

      Hello,


      could you please help me that how can I  define a nonlinear BC in (Blade) CFD Model.


      Thanks

    • December 11, 2019 at 8:36 am
      DrAmine
      Ansys Employee
      More details please.
    • January 22, 2020 at 8:47 am
      Hoosein86
      Subscriber

      Clould you please tell me wich Infos  or details you want to know?


      Best Regards


      Hossein

    • January 22, 2020 at 9:16 am
      DrAmine
      Ansys Employee

      Details about application, solver what you want to do?

    • January 22, 2020 at 9:23 am
      Hoosein86
      Subscriber

      The Model is in Fluent, and at my project I have to define a nonlinear BC in (Blade) CFD Model.


      My quastion is How can I do this?

    • January 22, 2020 at 9:31 am
      DrAmine
      Ansys Employee

      What do you mean with non linear boundary condition? What do you mean with (blade)?

    • January 22, 2020 at 9:37 am
      Hoosein86
      Subscriber

      this is the Topic of my Project : "Unsteady (Instationäre) flow simulation on a compressor stator grid using variable boundary conditions(Instationäre)" and I have to define a nonlinear BC.I have to finde a way to create a Non Linear BC.Hope you can help me.


      Best Regards


      Hossein

    • January 22, 2020 at 3:57 pm
      DrAmine
      Ansys Employee

      Yes: what is non-linear in your BCs?

    • January 29, 2020 at 9:51 am
      Hoosein86
      Subscriber

      I have to write an equation(Parameter)in inlet part that is related with time

    • January 29, 2020 at 1:21 pm
      DrAmine
      Ansys Employee

      Okay and what is now the issue with that equation? What are the dependent variables? Do you want to use UDF for that?

    • January 29, 2020 at 1:27 pm
      Hoosein86
      Subscriber

      I want to write an Equation that cause a Non-Linear BC.how?!


      the dependent variable could be the Z Coordinate.


      I an not sure how could be this Equation.


      Best regards


      Hossein


    • January 29, 2020 at 1:34 pm
      DrAmine
      Ansys Employee

      You can use an Expression for that. You require a bit more actual release. Another universal approach is to write DEFINE_PROFILE UDF. There are some example in the manual showing that.

    • January 29, 2020 at 1:44 pm
      Hoosein86
      Subscriber

      what do you mean to use Expression and actual release?


      BR


      Hossein

    • January 29, 2020 at 3:45 pm
      DrAmine
      Ansys Employee

      Using one of the latest versions of Fluent. Here you can use Expression not custom field function for profile description.

    • January 30, 2020 at 4:13 pm
      Hoosein86
      Subscriber

      Thanks for your answer.


      I want to write an Equation to Velocity that is not Constant, do you know what should I wtite to have No Unit to be able to calculate the Sinus Funktion ?


       


      Best Regards


      Hossein


    • January 30, 2020 at 4:14 pm
      DrAmine
      Ansys Employee
      Do not use that. You require UDF or Fluent Expression Custom field function are wrong here.
    • January 30, 2020 at 4:16 pm
      Hoosein86
      Subscriber

      First I have to write from custom field function.


      If it is not wort I will try UDF

    • January 30, 2020 at 4:28 pm
      DrAmine
      Ansys Employee
      It would not work from that only if you initialize and the custom field function in a profile and use that later as boundary profile
    • January 30, 2020 at 4:34 pm
      Hoosein86
      Subscriber

      Then How should I write UDF?


      using the custom ield function is much simple way to define the non steady flow.


      I have to write two Equations that change magnitude and Direction.

    • January 30, 2020 at 5:05 pm
      DrAmine
      Ansys Employee
      Yes or update to new version and use Expression. I hope you got it now.
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