ECO2M running stopped, unit temperature and pressure status abnormal
Dear TOUGH community users,
The model is established using Ansys apdl starting from 0 m, with the first unit below the surfacecenter serving as the wellhead unit. The aquifer reservoir is located at 800~850m (Supercritical CO2), and the wellbore extends to the bottom of the aquifer at 850m. The wellbore unit located in the reservoir is uniformly dispersed as 10m. The initial pressure distribution of the wellborereservoir system adopts a hydrostatic pressure gradient distribution, with surface pressure set at a standard atmospheric pressure of 0.1MPa.The pressure distribution is calculated based on P=0.1*10^6+1000 * 9.8h (h is the burial depth of the formation); The geothermal gradient is set at 25 ℃/1000m, the surface temperature is set at 10 ℃, and the temperature distribution of the wellborereservoir system is calculated based on T=10+0.025h (h is the burial depth of the formation); The lateral boundary of the model is the first type of boundary condition  constant pressure boundary (The Dirichlet boundary);The initial reservoir water saturation is 1.0, the CO2 mass fraction is 0, and the NaCl mass fraction is 0.lnject CO2 into the aquifer at pressure and temperature of 12 MPa, 25 ℃(pressure value higher than the saturation pressure of CO2 at the selected temperature,corresponding to an enthalpy value of 0.252528E+06 J/kg), with an injection rate of 10kg/s and a simulation time of 10 days.
During the simulation process, the program stopped running when it reached 0.640102E+06s (approximately 7d). The wellbore unit FG54 located in the reservoir experienced a pressure drop to 0.1000000 E+05Pa (the lower limit of the pressure value in the CO2TAB table) and a temperature rise to 290.0337 ℃. What is the reason for this situation and what adjustments should I make? I have attached the input file above. Thanks very much!
3 replies

where did you get the enthalpy value of 0.252528E+06 J/kg? ECO2M use different enthalpy value which is shifted from the data from NIST web book with a constant of 302192.0d0. If you get the enthalpy for NIST, you need input enthalpy by 0.252528E06+302192.0d0