I am currently working on my master’s thesis. I simulate scenarios of a geothermal doublet over multiple sandstone formations in OGS5.8. Therefore, I have set up an easy model with one sandstone layer surrounded by an almost impermeable mudstone above and below to do a sensitivity analysis.
As the mudstone is assumed to be impermeable, heat transport should only depend on thermal diffusivity in that area.
Changing the specific thermal conductivity and the thermal capacity of the mudstone counterwise to achieve the same thermal diffusivity, yields different simulation results for temperature.
No other parameters were changed in the simulations. Therefore, results were expected to be exactly the same.
I added three figures that show the results. Thermal diffusivity was 0.983 m²/s in all cases.
I already checked if the very low (1e-19 m²) permeability of the mudstone still has an influence, but it does not.
Now I don’t know how to fix this problem anymore.
I added the input files of the base case and would appreciate any help!
Thanks in advance.
Neuer Ordner.zip (5.1 MB)