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The Example in TOUGH2's ECO2N:Radial Flow from a CO2 Injection Well

Dear all, 

I am using TOUGH2 ECO2N and I have confused about the example in Page 28 of the manual ECO2N: A TOUGH2 Fluid Property Module for Mixtures of Water, NaCl which called ‘Radial Flow from a CO2 Injection Well’.I would like to know the following issues:(image 1 describe the related settings,image 2 describe the mesh files,image 3 is the Schematic of sample problem)

(1)What is the significance of setting the density of well to infinity

(2) why it is not necessary to set its specific enthalpy when injecting co2?

(3)What is the significance of setting the node distance to infinitely small

(4)How it works after setting these things up?

 

Kind regards,

Luo Yuhao

5 replies

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    • Reservoir Engineer
    • Alfredo_b
    • 1 yr ago
    • Reported - view

    Dear Luo,

    two cases are simulated, one is a isothermal problem in which the energy balance equation is not solved (NEQ=3), the second is a non-isothermal problem (NEQ=4) in which the wellbore injection T is held constant at the initial reservoir T of 45°C.

    (1) in order to run non-isothermally but with a constant injection T, the rock thermal energy of wellbore block needs to be numerically infinite, either by assigning an infinite rock density and/or an infinite rock specific heat. 

    (2) CO2 injection enthalpy can be omitted in both cases. Actually TOUGH2 reads 0 J/kg as CO2 injection enthalpy. This value does not affect the simulations because for the isothermal case the thermal energy balance is simply not solved, while for the non-isothermal case the CO2 injection enthalpy has an insignificant contribution to the energy balance of wellbore block due to the infinite rock thermal energy.

    (3) Setting the wellbore block node distance to zero simply reduces the P losses inside the wellbore to a negligible value as we can expect, assuming the wellbore P is applied directly at the sand face.

    (4) By using the above input assignments, you should be able to replicate the user's guide simulations for both isothermal and non-isothermal cases.

    The user's guide describes the use of the above input assignments quite clearly. Having a look to TOUGH2 balance equations helps in following the user's guide description.

    Regards,

    Alfredo

      • denim_scarf
      • 1 yr ago
      • Reported - view

      Alfredo I have one more question can I achieve non-isothermal simulation by specifying the enthalpy of co2 instead of assuming the infinite density of the wellbore?Thank you so much and best wishes for you!

      • Reservoir Engineer
      • Alfredo_b
      • 1 yr ago
      • Reported - view

      上衫绘梨衣 

      The second case above is related to a non-isothermal simulation in which the bottom-hole injection T is held constant by specifying an infinite rock density.

      If you want to run a non-isothermal simulation at a constant bottom-hole injection enthalpy, then use a negligible rock density value (no rock inside the wellbore) and the value of bottom-hole CO2 injection enthalpy you want to assign. You need to determine the CO2 enthalpy value, at desired P&T conditions, by using ECO2N.

      Alfredo

      • denim_scarf
      • 1 yr ago
      • Reported - view

      Alfredo Battistelli Thank you for your patience and have a great day!😄

    • Prince_Kumar.1
    • 1 yr ago
    • Reported - view

    Hello 

    I am solving ECO2M Example: CO2 Injection Well but after a successful TOUGH2.1 run I am unable to plot the 3D results. If you solved this already Could you please help me?

    After clicking on 3D results. The error tab shows that "Could not load results: Results file not found". 

    I checked the project folder and there are no .csv (Excel) files. 

     

    Query link:  https://tough.forumbee.com/t/h7yhx7j/results-file-not-found-eco2m-tough-v2-1-no-csv-file-generated

     

Content aside

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