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Autodyn subroutine issue – ideal gas EOS

    • Myunghyun Shin
      Subscriber

      I am a mechanical engineering student studying autodyn subroutines.

       

      I encountered an issue while implementing the ideal gas equation of state using a subroutine, so I am writing to seek assistance.

       

      I have written a subroutine code as shown below.

      When I attempt to build the code, I encounter an error as depicted in the image. Also, nothing happens when subroutine code is simulated in Autodyn.

       

      I am curious whether there are issues in the parts of the code where variable values are fetched and stored (getmlt, putmlt), or in the EOS calculation section (solve_eos_user1).

       

      Thanks and best regards,

      Myunghyun Shin

    • Chris Quan
      Ansys Employee

      The error message indicates that there was a problem with the calculation of the PP due to the use of an array. 

      Please check the definition of the PP in your user subroutine.

      PP in the default Autodyn user subroutine is not an array. The user subroutines in the mdeos_user_1.f90 is called by every element at every time step. All the variables, PP, EE, P0, E0, etc are not an array.

      How is the gamma defined? If it is defined by user-defined variable from Autodyn GUI, it is an array. Make sure the gamma is a constant, not an array.

       

      • Myunghyun Shin
        Subscriber

        Thanks for you kind response!

        As you mentioned, "variable gamma" is defined in "Module EOS_USER_1" just like the picture below(variable "rho" also!).

        I changed the array size to "Dimension 1" just like your comment.

        However, after I changed the array size of "variable gamma" to 1, the same error has occurred.

        Why has the error occurred? I still have no idea about it.

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