ECO2N Steady state

Hi everybody!

I'm a new Tough2 ECO2N user and i'm experiencing some problems by reaching the steady state condition... I will use it as Initial conditions for the simulations.

Now i'm running the simulator for 100 years without CO2 injection rate at all, althouhgh the poligonyal mesh was created after well implantation.

it was suppose to reach steady state rapidly, but it runs until the end of the time. I've tried to run it as isothermal model, but it didn't reach the steady state too, meaning that there is no problem with temperature files, i guess. 

What can i do to reach the steady state? What are the drivers for steady state condition?

Thank you so much for your help,

Best Regards

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  • Hi, luis, I think you can extend the computing time,  such as  1000 years or 10000 years if necessary, good luck!


  • Ok, I'll try it!

    Thank you!

  • Hi everybody,


    I've tried to run it for 10e6 years and the simulation has halted prematurely and i can't understand why?

    Can anybody help please?


    Thank you very much!

    Please find attached the primary report and the last interaction line on the report:

  • Luis,

    It seems you have reached steady state, as repeated convergence within one Newton-Raphson iteration was achieved - look for a related statement just before the final output (not shown in your screen shots).


  • Hi again,


    I've searched on .out file and it is as this attached. 

    Can somebody tell me what does this mean? i've opened the file and they are empty..


    Many thanks in advance,

  • Hi Stefan,


    Thank you! I've looked for, but i'm afraid that i can't find it on this screenshot:

    Is CYCIT related to that?

    Just one more thing, once it reaches the steady state, it displays "steady state reached" every time or some times doesn't?

    Thank you very much!

  • Luis,

    I apologize; I did not see the full output from the (PetraSim?) screen shot (I'm on travel and have very slow internet connection, and only got to download the upper half of file ...47.png).

    The conclusion remains the same, though: You have reached steady state! The final time step is very large, and follows a long seuqnece of convergence within a single Newton-Raphson iteration. The convergence failure you highlighted in red indicates that the Newton-Raphson iterations try to determine the root of numerical round-off errors rather than actual changes in the primary variables. This may happen when approaching steady state (an attempt to solving 0=0).

    Also, check your elements and sink/sources in the GENER and GOFT blocks.


  • Thank you very much Stefan!

    I'll check it out!

  • Dear Stefan,


    Thank you once again for the tips.

    I've run the program and it says "no converge in NSIN at 1512 for (T, XS,XLCO2)"...

    I'm experiencing this kind of problem regularly and on puzzling way... and i can't find the problem. It might be temperature related but i find it difficult to be...

    what can it be?

    Please feel free if you do you want me to send you part of .out file.


    Thank you very much once again,


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