Methods and systems for flow-based coarsening of reservoir grid models

Patent metadata

Field	Value
Publication number	US-11754745-B2
Application number	US-202016916978-A
Country	US
Kind code	B2
Filing date	Jun 30, 2020
Priority date	Jun 30, 2020
Publication date	Sep 12, 2023
Grant date	Sep 12, 2023

Abstract

A method may include obtaining model data for a reservoir region of interest. The model data may include flow property data based on streamlines. The method may further include generating a multilevel coarsening mask describing various coarsening levels that correspond to different flow values among the flow property data. The method may further include generating a coarsened grid model using the model data and the multilevel coarsening mask. The method may further include performing a reservoir simulation of the reservoir region of interest using the coarsened grid model.

First claim

What is claimed:

1. A method, comprising:
performing, by a computer processor, a first reservoir simulation of a reservoir region of interest using a first grid model to produce a first plurality of streamlines;
obtaining, by the computer processor, model data for the reservoir region of interest;
generating, by the computer processor, a multilevel coarsening mask describing a plurality of coarsening levels that correspond to different flow values among flow property data based on the first plurality of streamlines;
generating, by the computer processor, a first coarsened grid model using the model data and the multilevel coarsening mask;
performing, by the computer processor, a second reservoir simulation of the reservoir region of interest using the first coarsened grid model to produce a second plurality of streamlines;
performing, by the computer processor, a comparison of the first plurality of streamlines with the second plurality of streamlines;
adjusting, by the computer processor, the multilevel coarsening mask based on the comparison to produce an updated multilevel coarsening mask;
updating, by the computer processor, the first coarsened grid model based on the model data and the updated multilevel coarsening mask to produce a second coarsened grid model; and
performing, by the computer processor, a third reservoir simulation of the reservoir region of interest using the second coarsened grid model.

2. The method of claim 1 ,
wherein the multilevel coarsening mask is determined using a lookup table describing a plurality of coarsening values based on predetermined ranges of flow rate property values, and
wherein the multilevel coarsening mask is an integer mask.

3. A method of claim 1 ,
wherein the multilevel coarsening mask is an adjusted property mask comprising a smoothed grid region, and
wherein the smoothed grid region is produced by performing an edge smoothing operation to an expanded grid region.

4. A method of claim 1 ,
wherein the first coarsened grid model is generated using a plurality of local grid refinement and coarsening (LGR) object statements that are determined using a decomposition algorithm and one or more binary masks.

5. A method of claim 1 ,
wherein the first coarsened grid model is based on a coarsening scenario generated using a combinatorial algorithm.

6. A computer system, comprising:
a processor; and
a memory coupled to the processor, the memory comprising instructions, when executed by the processor, are configured to perform a method comprising:
performing a first reservoir simulation of a reservoir region of interest using a first grid model to produce a first plurality of streamlines;
obtaining model data for the reservoir region of interest;
generating a multilevel coarsening mask describing a plurality of coarsening levels that correspond to different flow values among flow property data based on the first plurality of streamlines;
generating a first coarsened grid model using the model data and the multilevel coarsening mask;
performing a second reservoir simulation of the reservoir region of interest using the first coarsened grid model to produce a second plurality of streamlines;
performing a comparison of the first plurality of streamlines with the second plurality of streamlines;
adjusting the multilevel coarsening mask based on the comparison to produce an updated multilevel coarsening mask;
updating the first coarsened grid model based on the model data and the updated multilevel coarsening mask to produce a second coarsened grid model; and
performing a third reservoir simulation of the reservoir region of interest using the second coarsened grid model.

7. The computer system of claim 6 ,
wherein the multilevel coarsening mask is determined using a lookup table describing a plurality of coarsening values based on predetermined ranges of flow rate property values, and
wherein the multilevel coarsening mask is an integer mask.

8. The computer system of claim 6 ,
wherein the multilevel coarsening mask is an adjusted property mask comprising a smoothed grid region, and
wherein the smoothed grid region is produced by performing an edge smoothing operation to an expanded grid region.

9. A non-transitory computer readable medium storing instructions executable by a computer processor, the instructions being configured to perform a method comprising:
performing a first reservoir simulation of a reservoir region of interest using a first grid model to produce a first plurality of streamlines;
obtaining model data for the reservoir region of interest;
generating a multilevel coarsening mask describing a plurality of coarsening levels that correspond to different flow values among flow property data based on the first plurality of streamlines;
generating a first coarsened grid model using the model data and the multilevel coarsening mask;
performing a second reservoir simulation of the reservoir region of interest using the first coarsened grid model to produce a second plurality of streamlines;
performing a comparison of the first plurality of streamlines with the second plurality of streamlines;
adjusting the multilevel coarsening mask based on the comparison to produce an updated multilevel coarsening mask;
updating the first coarsened grid model based on the model data and the updated multilevel coarsening mask to produce a second coarsened grid model; and
performing a third reservoir simulation of the reservoir region of interest using the second coarsened grid model.

10. The non-transitory computer readable medium of claim 9 ,
wherein the multilevel coarsening mask is an adjusted property mask comprising a smoothed grid region, and
wherein the smoothed grid region is produced by performing an edge smoothing operation to an expanded grid region.

11. The non-transitory computer readable medium of claim 9 ,
wherein the first coarsened grid model is generated using a plurality of local grid refinement and coarsening (LGR) object statements that are determined using a decomposition algorithm and one or more binary masks.

12. The non-transitory computer readable medium of claim 9 ,
wherein the first coarsened grid model is based on a coarsening scenario generated using a combinatorial algorithm.

Assignees

• Saudi Arabian Oil Co

Inventors

• Kayum Suha Naim
• Rogowski Marcin
• Cancelliere Michel
• Crumpton Paul

Classifications

• E21B49/00 Primary

  Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells · CPC title

• E21B2200/20

  Computer models or simulations, e.g. for reservoirs under production, drill bits · CPC title

• E21B43/00

  Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells (applicable only to water E03B) · CPC title

• G06F2113/08

  Fluids · CPC title

• G06F30/23

  using finite element methods [FEM] or finite difference methods [FDM] · CPC title