Analysis of Changes in the Stress–Strain State and Permeability of a Terrigenous Reservoir Based on a Numerical Model of the Near-Well Zone with Casing and Perforation Channels
A finite element model, which includes reservoir rock, cement stone, casing, and perforation channels, was developed. The purpose of the study is to create a geomechanical model of the zone around the well, which includes support elements and perforation channels. This model will help predict change...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-11-01
|
| Series: | Applied Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2076-3417/14/21/9993 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850193514996957184 |
|---|---|
| author | Sergey Chernyshov Sergey Popov Xiaopu Wang Vadim Derendyaev Yongfei Yang Huajie Liu |
| author_facet | Sergey Chernyshov Sergey Popov Xiaopu Wang Vadim Derendyaev Yongfei Yang Huajie Liu |
| author_sort | Sergey Chernyshov |
| collection | DOAJ |
| description | A finite element model, which includes reservoir rock, cement stone, casing, and perforation channels, was developed. The purpose of the study is to create a geomechanical model of the zone around the well, which includes support elements and perforation channels. This model will help predict changes in the productivity coefficient of a terrigenous reservoir and determine the most efficient mode of operation of a producing well. In order to exclude the stress concentration within the casing–cement stone and cement stone–rock, the numerical model applies contact elements. As a result, structural elements slip, while the stresses are redistributed accurately. The numerical simulation of a stress state in the near-well zone was carried out by using the developed model with differential pressure drawdown on the terrigenous reservoir, one of the oil fields in the Perm region. It is shown that the safety factor of the casing reaches roughly 3–4 units. The only exceptions are the upper and lower parts of the perforations, where this parameter is close to one unit. The safety factor of cement stone accounts for 2–3 units. However, parts with its lowest value (1.35) are also concentrated near the perforation channels. In order to analyze the change in permeability, the dependence of the safety factor on effective stresses was taken into account. Therefore, it was found that, in the upper and lower parts of perforations, the stresses decreased, while permeability rose by up to 20% of the initial value. An increase in differential pressure drawdown, on the contrary, can lead to a permeability reduction of 25%, especially in the lateral parts of the perforations. Areas of rock destruction under tensile and compressive forces were identified by using the Mohr–Coulomb criterion. It is estimated that with an increase in pressure drawdown, the areas of rock destruction under tensile force disappear, while the areas of rock destruction under compression increase. After further analysis, it was found that, with the maximum pressure drawdown of 12 MPa, the well productivity index can decrease by 15% due to the reservoir rock compaction. |
| format | Article |
| id | doaj-art-4df54f5709ca4dad96dc9da2351a8a41 |
| institution | OA Journals |
| issn | 2076-3417 |
| language | English |
| publishDate | 2024-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj-art-4df54f5709ca4dad96dc9da2351a8a412025-08-20T02:14:15ZengMDPI AGApplied Sciences2076-34172024-11-011421999310.3390/app14219993Analysis of Changes in the Stress–Strain State and Permeability of a Terrigenous Reservoir Based on a Numerical Model of the Near-Well Zone with Casing and Perforation ChannelsSergey Chernyshov0Sergey Popov1Xiaopu Wang2Vadim Derendyaev3Yongfei Yang4Huajie Liu5Oil and Gas Technologies Department, Perm National Research Polytechnic University, 614990 Perm, RussiaInstitute of Oil and Gas Problems of the Russian Academy of Sciences, 119333 Moscow, RussiaSchool of Petroleum Engineering, China University of Petroleum, Qingdao 266580, ChinaOil and Gas Technologies Department, Perm National Research Polytechnic University, 614990 Perm, RussiaSchool of Petroleum Engineering, China University of Petroleum, Qingdao 266580, ChinaSchool of Petroleum Engineering, China University of Petroleum, Qingdao 266580, ChinaA finite element model, which includes reservoir rock, cement stone, casing, and perforation channels, was developed. The purpose of the study is to create a geomechanical model of the zone around the well, which includes support elements and perforation channels. This model will help predict changes in the productivity coefficient of a terrigenous reservoir and determine the most efficient mode of operation of a producing well. In order to exclude the stress concentration within the casing–cement stone and cement stone–rock, the numerical model applies contact elements. As a result, structural elements slip, while the stresses are redistributed accurately. The numerical simulation of a stress state in the near-well zone was carried out by using the developed model with differential pressure drawdown on the terrigenous reservoir, one of the oil fields in the Perm region. It is shown that the safety factor of the casing reaches roughly 3–4 units. The only exceptions are the upper and lower parts of the perforations, where this parameter is close to one unit. The safety factor of cement stone accounts for 2–3 units. However, parts with its lowest value (1.35) are also concentrated near the perforation channels. In order to analyze the change in permeability, the dependence of the safety factor on effective stresses was taken into account. Therefore, it was found that, in the upper and lower parts of perforations, the stresses decreased, while permeability rose by up to 20% of the initial value. An increase in differential pressure drawdown, on the contrary, can lead to a permeability reduction of 25%, especially in the lateral parts of the perforations. Areas of rock destruction under tensile and compressive forces were identified by using the Mohr–Coulomb criterion. It is estimated that with an increase in pressure drawdown, the areas of rock destruction under tensile force disappear, while the areas of rock destruction under compression increase. After further analysis, it was found that, with the maximum pressure drawdown of 12 MPa, the well productivity index can decrease by 15% due to the reservoir rock compaction.https://www.mdpi.com/2076-3417/14/21/9993stress–strain statepermeabilitynumerical finite element modelcement stonenear-well zonedifferential pressure drawdown |
| spellingShingle | Sergey Chernyshov Sergey Popov Xiaopu Wang Vadim Derendyaev Yongfei Yang Huajie Liu Analysis of Changes in the Stress–Strain State and Permeability of a Terrigenous Reservoir Based on a Numerical Model of the Near-Well Zone with Casing and Perforation Channels Applied Sciences stress–strain state permeability numerical finite element model cement stone near-well zone differential pressure drawdown |
| title | Analysis of Changes in the Stress–Strain State and Permeability of a Terrigenous Reservoir Based on a Numerical Model of the Near-Well Zone with Casing and Perforation Channels |
| title_full | Analysis of Changes in the Stress–Strain State and Permeability of a Terrigenous Reservoir Based on a Numerical Model of the Near-Well Zone with Casing and Perforation Channels |
| title_fullStr | Analysis of Changes in the Stress–Strain State and Permeability of a Terrigenous Reservoir Based on a Numerical Model of the Near-Well Zone with Casing and Perforation Channels |
| title_full_unstemmed | Analysis of Changes in the Stress–Strain State and Permeability of a Terrigenous Reservoir Based on a Numerical Model of the Near-Well Zone with Casing and Perforation Channels |
| title_short | Analysis of Changes in the Stress–Strain State and Permeability of a Terrigenous Reservoir Based on a Numerical Model of the Near-Well Zone with Casing and Perforation Channels |
| title_sort | analysis of changes in the stress strain state and permeability of a terrigenous reservoir based on a numerical model of the near well zone with casing and perforation channels |
| topic | stress–strain state permeability numerical finite element model cement stone near-well zone differential pressure drawdown |
| url | https://www.mdpi.com/2076-3417/14/21/9993 |
| work_keys_str_mv | AT sergeychernyshov analysisofchangesinthestressstrainstateandpermeabilityofaterrigenousreservoirbasedonanumericalmodelofthenearwellzonewithcasingandperforationchannels AT sergeypopov analysisofchangesinthestressstrainstateandpermeabilityofaterrigenousreservoirbasedonanumericalmodelofthenearwellzonewithcasingandperforationchannels AT xiaopuwang analysisofchangesinthestressstrainstateandpermeabilityofaterrigenousreservoirbasedonanumericalmodelofthenearwellzonewithcasingandperforationchannels AT vadimderendyaev analysisofchangesinthestressstrainstateandpermeabilityofaterrigenousreservoirbasedonanumericalmodelofthenearwellzonewithcasingandperforationchannels AT yongfeiyang analysisofchangesinthestressstrainstateandpermeabilityofaterrigenousreservoirbasedonanumericalmodelofthenearwellzonewithcasingandperforationchannels AT huajieliu analysisofchangesinthestressstrainstateandpermeabilityofaterrigenousreservoirbasedonanumericalmodelofthenearwellzonewithcasingandperforationchannels |