0

EOS3-sink/source rates are piecewise constant, how to set up?

As mentioned in the title, I want to set the piecewise constant  sink/source rate as shown in the attached figure, but I can't achieve the desired result after setting it many times in petrasim, can anyone give me some help, I am very eager to know how to set this step?Thank you very much!

8 replies

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

    Dear Chu,

    if you want to use the Wells option in Petrasim, you need to assign the variable production and injection schedule in the Wells/flow  window by assigning times-rates for the production and time-rates-enthalpy for the injection periods :

    - production \ mass out \ Rate = Table : assign time-rates schedule

    - injection \ water/steam   \  Rate = table : assign time-rate-enthalpy schedule.

    In order to exactly reproduce your production/injection schedule, it is better to use the Rigorous step option under "solution control\options\MOP(12)".

    In addition, better to set optional printout at the times corresponding to rate changes. In this way there will be no interpolation during  time steps including a rate change.

    You can view the results under Results\Well plots, where you will find 1 sink (MASS) and 1 source (COM1). Results are saved in file GOFT. Of course you have to request the printout under Wells\print options.

    Take the attached Petrasim file as an example of the above choices (Petrasim 2020.2.1222 x64).

    Regards,

    Alfredo

      • Zhubin_Chu
      • 1 yr ago
      • Reported - view

      Alfredo Dear Alfredo,

      Thank you very much for your reply

      • Zhubin_Chu
      • 1 yr ago
      • Reported - view

      Alfredo Battistelli 

      Dear Alfredo.
      I am very sorry to disturb you again, according to your instructions I set a set of parameters that I need to simulate to inject air and produce air at a rate of 0.6kg/s. During the injection phase, the calculation went very well. However, unfortunately, when I set the production, Petrasim started reporting errors soon after the calculation, also I was producing at 0.6kg/s, but when I changed the production rate to 0.1kg/s, the calculation worked fine, I would like to know why this is, the volume of the well unit in my model is 0.1m x 0.1m x 3m. Is it because the volume of the well unit is too small? To be honest, I don't really understand the use of this production function.

      I regret your sim file version is high I can not open, attached is a set of parameters I set, I sincerely hope to get your advice.

      I am very eager to your reply!

      Thank you and best regards,

      Chu

      Translated with DeepL

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

      Zhubin Chu 

      With the info supplied I cannot help you.

      Looking at the output file and in particular to the history of well blocks, you can easily check if the P drops to too low values during production. The fact that the simulation proceeds with a lower extraction rate confirms the above hypothesys.

      This might be the reason for the premature end of the run. This may happen when using MASS extraction option, as the code simply tries to extract the assigned rate, even if it is too high for assigned formation properties. A better option could be to use a DELV approach by evaluating the PI depending on your grid shape and setting a wellbore pressure suitable for wellbore flowing conditions.

      Look first at TOUGH2 user's guide and then to Petrasim documentation if you need more info on how to handle sink/sources.

      About the *.sim file I sent you, the attached screen shots show how to set both production and injection history at the same well.

      Alfredo

      • Zhubin_Chu
      • 1 yr ago
      • Reported - view

      Alfredo Battistelli thank you for your reply and best wishes for you.

      • Zhubin_Chu
      • 1 yr ago
      • Reported - view

      Alfredo Battistelli 

      Dear Alfredo.
      I am sorry to disturb you, I recently saw a very interesting way to discretize the mesh in a paper as shown in the attached picture, but I tried to do it in petrasim without success, do I need to use other tools to achieve this ? I am very eager to know how to achieve this. Thank you very much!

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

      Zhubin Chu 

      There are different codes available to build discretization grids like those shown. You can find the main ones on the TOUGH page (https://tough.lbl.gov/pre-and-post-processors/).

      The main problem in Petrasim is that while the code has an algorithm to build discretisation grids preserving the requirement of IFDM, including unstructured Voronoi meshes, user's ability to control the mesh building is rather limited. You should supply the list of element nodes to Petrasim using the option allowing to give the points where a grid refinement is wanted, such as for wells location. Then you should choose the minimum element area requested by Petrasim to avoid the code will add additional nodes to those you supplied.

      Apart for some problems to control the grid shape at the boundaries of the modeled area, Petrasim should build a grid honoring your input nodes and IFDM requirements. That was shown in an old post (How to create meshes with local grid refinements).

      I replicate for convenience two of the images from previous post. The first one is a sample grid made using AMESH which you find on LBNL TOUGH page. The nodes where generated using a simple FORTRAN program allowing to define nested cartesian grids and nodes around wells.

      The second one has been generated with Petrasim by supplying the list of nodes as refining points for the unstructured Voronoi grid option. The grid is the same, apart the mentioned issue to replicate the exact gridding on the model boundaries. Thus, the main problem is to generate the list of nodes outside Petrasim.

      Likely there are smarter ways to build such grids inside Petrasim, or better, to allow Petrasim to use grids generated externally with some other code. I'm also interested to have additional suggestions.

      Regards,

      Alfredo

      • Zhubin_Chu
      • 1 yr ago
      • Reported - view

      Alfredo Battistelli Thank you very much, Alfredo!

Content aside

  • 1 yr agoLast active
  • 8Replies
  • 103Views
  • 2 Following