Investigation of the Effect of Capillary Barrier on Water–Oil Movement in Water Flooding
Water flooding technology is widely used to improve oil recovery efficiency in oilfields. The capillary barrier effect induced by the complex pore structures in the reservoir rocks is a crucial reason for the trapping of a great deal of residual oil in oil reservoirs after water flooding. However, t...
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MDPI AG
2022-06-01
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| Series: | Applied Sciences |
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| author | Bingtao Hu Zhaolin Gu Chenxing Zhou Le Wang Chuanqing Huang Junwei Su |
| author_facet | Bingtao Hu Zhaolin Gu Chenxing Zhou Le Wang Chuanqing Huang Junwei Su |
| author_sort | Bingtao Hu |
| collection | DOAJ |
| description | Water flooding technology is widely used to improve oil recovery efficiency in oilfields. The capillary barrier effect induced by the complex pore structures in the reservoir rocks is a crucial reason for the trapping of a great deal of residual oil in oil reservoirs after water flooding. However, the formation condition along with the effect on the recovery rate of the capillary barrier under different wettability conditions should be investigated further. To bridge the gap between the microscopic mechanism of the capillary barrier effect and the macroscopic mechanism of oil displacement efficiency, a simple conceptual capillary model is constructed to obtain the formation conditions of the capillary barrier using the analysis method, and its influence on macroscopic oil displacement efficiency in the porous media model with an opening angle of 45° is systematically investigated in this study using direct numerical simulations (DNS) coupled with the volume of fluid method. The results showed that the capillary barrier effect plays a significant role in the formation of the residual oil in the reservoir rock and the contact angle and the opening angle are the primary factors for the formation of the capillary barrier. The capillary force is the driving force when the oil–water interface advances in the throat channel under water-wet conditions, while the capillary force hinders the movement of oil–water movement when the liquid flows out of the throat channel and when <i>θ</i> + <i>β</i> > 90<sup>o</sup>. Furthermore, the highest oil displacement efficiency is achieved at the intermediate capillary number and in the case that the minimum conditions of occurrence of the capillary barrier phenomenon are satisfied. This is of great significance for controlling the optimized contact angle to further enhance the oil recovery rate of current oil reservoirs using waterflooding technology. |
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| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-10T00:27:22Z |
| publishDate | 2022-06-01 |
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| spelling | doaj.art-1c789091b2df42f5bb19ae809c9f582e2023-11-23T15:30:56ZengMDPI AGApplied Sciences2076-34172022-06-011212628510.3390/app12126285Investigation of the Effect of Capillary Barrier on Water–Oil Movement in Water FloodingBingtao Hu0Zhaolin Gu1Chenxing Zhou2Le Wang3Chuanqing Huang4Junwei Su5School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaSchool of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaSchool of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaMechanical Engineering College, Xi’an Shiyou University, Xi’an 710065, ChinaSchool of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi’an 710021, ChinaSchool of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaWater flooding technology is widely used to improve oil recovery efficiency in oilfields. The capillary barrier effect induced by the complex pore structures in the reservoir rocks is a crucial reason for the trapping of a great deal of residual oil in oil reservoirs after water flooding. However, the formation condition along with the effect on the recovery rate of the capillary barrier under different wettability conditions should be investigated further. To bridge the gap between the microscopic mechanism of the capillary barrier effect and the macroscopic mechanism of oil displacement efficiency, a simple conceptual capillary model is constructed to obtain the formation conditions of the capillary barrier using the analysis method, and its influence on macroscopic oil displacement efficiency in the porous media model with an opening angle of 45° is systematically investigated in this study using direct numerical simulations (DNS) coupled with the volume of fluid method. The results showed that the capillary barrier effect plays a significant role in the formation of the residual oil in the reservoir rock and the contact angle and the opening angle are the primary factors for the formation of the capillary barrier. The capillary force is the driving force when the oil–water interface advances in the throat channel under water-wet conditions, while the capillary force hinders the movement of oil–water movement when the liquid flows out of the throat channel and when <i>θ</i> + <i>β</i> > 90<sup>o</sup>. Furthermore, the highest oil displacement efficiency is achieved at the intermediate capillary number and in the case that the minimum conditions of occurrence of the capillary barrier phenomenon are satisfied. This is of great significance for controlling the optimized contact angle to further enhance the oil recovery rate of current oil reservoirs using waterflooding technology.https://www.mdpi.com/2076-3417/12/12/6285capillary barrierflow in porous mediapore-scale simulationenhanced oil recoverywettability |
| spellingShingle | Bingtao Hu Zhaolin Gu Chenxing Zhou Le Wang Chuanqing Huang Junwei Su Investigation of the Effect of Capillary Barrier on Water–Oil Movement in Water Flooding Applied Sciences capillary barrier flow in porous media pore-scale simulation enhanced oil recovery wettability |
| title | Investigation of the Effect of Capillary Barrier on Water–Oil Movement in Water Flooding |
| title_full | Investigation of the Effect of Capillary Barrier on Water–Oil Movement in Water Flooding |
| title_fullStr | Investigation of the Effect of Capillary Barrier on Water–Oil Movement in Water Flooding |
| title_full_unstemmed | Investigation of the Effect of Capillary Barrier on Water–Oil Movement in Water Flooding |
| title_short | Investigation of the Effect of Capillary Barrier on Water–Oil Movement in Water Flooding |
| title_sort | investigation of the effect of capillary barrier on water oil movement in water flooding |
| topic | capillary barrier flow in porous media pore-scale simulation enhanced oil recovery wettability |
| url | https://www.mdpi.com/2076-3417/12/12/6285 |
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