Fluids

Fluids

User Defined Real Gas Model floating point exception

    • astrotoma
      Subscriber

      Hello,


      I have been struggling with implementing a user defined real gas model in Fluent 19.2. To begin with, I am using the example ideal gas UDRGM provided in the Users Guide, copied line for line and I can't get it to work. 


      The ideal gas UDRGM has been taken from https://www.sharcnet.ca/Software/Fluent6/html/ug/node379.htm.


       The case I'm running is extremely simple. It is a square tube with a mass flow inlet and a pressure outlet. It successfully converged with ideal-gas air as the chosen material.


        


      Using Visual Studio 2017 I successfully compile and load the UDRGM library. The console output is as follows:




      Using the TUI I set the material to the compiled UDRGM, I initialize the case and hit Calculate and immediately without a single iteration this error is thrown:




      I have tried this with the Redlich-Kwong EOS example UDRGM as well and the same error props up. What is happening here, how do I avoid it?

    • DrAmine
      Ansys Employee
      Check if you are using the example from the documentation 19.2
    • astrotoma
      Subscriber

      Where can I find the newest documentation?


      Thank you!

    • DrAmine
      Ansys Employee
      Just hit F1 in Fluent.
    • DrAmine
      Ansys Employee
      Just hit Fone or click on help in Fluent
    • astrotoma
      Subscriber

      Tried it, still get the same error. 

    • Rob
      Ansys Employee

      If you plug the temperature, pressure etc from the initial solution into the UDF code what density etc does it give? How does that compare to the value in the initial data?

Viewing 6 reply threads
  • You must be logged in to reply to this topic.