Model divergence

i have simplified the model to bare minimum, however i am getting an error message. help please, before i give up.

Hello mpetraits
thanks for reaching out to us here in the forum.

Can you please share a link to your project with the forum so that we can have a look at it ?

Best regards
Sebastian

Oh thank you. Here is a link:

The dimentions are in meters. The project is for deep well geothermal situation, where the depth of the borehole is approx 6km, the flow of water is 60m2/s , the thermal gradient of the rock is 30C/km, the are of land assumed in a simulation is 3*3km, so the borehole is tiny in relation to overall model. The intention is to analyze the heat transfer (from cold injected water to rock and vice versa) over a period of time (say 1 year). Also the question is - what time it would take for the rock temperature to stabilize under constant influx of cool water.

The model was produced in rhino; it has been scaled down when imported, so i had to scale it up by a factor of 1000.

I really hope you can help me, thank You.