Posted Tue, 18 Nov 2014 11:17:17 GMT by mili111
Hello all,

I have to model a BHE field (only 5) für my MSc Thesis.
When i run my model to validate it with MATLAB, i used a constant Power for my first BHE, which was -40 MJ/d.
So there everything was fine and it matches with the MATLAB calculation.

But now i built a timeseries for 10 years, and always after exactly one year the model explodes! Temperatures rise above several hundreds °C and my cooling flag break away. I even tried to discretisize my model more, but then i get this error after one month "Incomplete satisfaction of flow constraints within 30 iterative cycles at time=3.100000e+001 [d]. Termination of cycling".
I also set lower time steps (one day) but no success.
Right now i run the model without more refinements (original model from the beginning) but set the time steps to half a day, but now the cooling flag breaks after one month! When this happens my time steps go down to xx*10^-5. The only error FEFLOW gives me here is: "Math: Argument domain error in function sqrt!"

I hope anyone can help me, im realy desperate. I only have 2-3 weeks to get the model done, and i dont have any idea what is my fault.

Here you can see my burst model:

Kind regards, Michael
Posted Wed, 19 Nov 2014 16:00:35 GMT by Björn Kaiser
Hello Michael,

If you like I may have a closer look to your model. Please send us an e-mail in the FEFLOW support:


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