The correct well testing data interpretation is of particular interest in case of injection wells with the induced fractures (waterflooding fractures) that occur due to the high injection pressure. Standard software used for the well testing simulation does not have the functionality to model filtration processes with hydraulic fractures of varying geometry and conductivity. The coupled hydrogeomechanical model accounting the waterflooding fractures is used in this work for the interpretation of field experiment data. The well test is simulated in two selected areas of oil fields with wells oriented along maximum region stress. In the first case, one vertical injection well surrounded by production wells is considered. In the second one, the sector of the field development system is treated. The sector includes two horizontal injection wells with multi-stage hydrofracturing and production wells located nearby. It is shown that in the both cases the model pressure curves are in an acceptable agreement with the field data. The comparison of the field data with the results of the standard well test modeling shows that the discrepancy occurs when the fracture length changes. In the case of the sector of field development system, the model is able to simulate the performance of two injection wells simultaneously. Numerical calculations expose the possibility of main fracture growth between two injection wells. During the pressure falloff test, the fractures close quickly due to the large leaks into the formation. When the injection is resumed, the waterflooding fractures grow rapidly and merge into the main fracture. The fracture propagation rate is used to improve the multiphase hydrodynamic model. The hydrodynamic simulations demonstrate the possible positive impact of the waterflooding fracturing on the economic performance of the development system by reducing the number of injection wells.
References
1. Davletbaev A., Asalkhuzina G., Ivaschenko D. et al., Methods of research for the development of spontaneous growth of induced fractures during flooding in low permeability reservoirs (In Russ.), SPE-176562-MS, 2015, DOI: https://doi.org/10.2118/176562-MS
2. Kalinin S.A., Baykin A.N., Abdullin R.F. et al., Modeling and analysis of hydraulic fractures coalescence during waterflooding in a direct line drive pattern (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 12, pp. 40–45, DOI: https://doi.org/10.24887/0028-2448-2022-12-40-45
3. Baykin A.N., Abdullin R.F., Dontsov E.V., Golovin S.V., Two-dimensional models for waterflooding induced hydraulic fracture accounting for the poroelastic effects on a reservoir scale, Geoenergy Sci. Eng., 2023, V. 224, Article no. 211600, DOI: https://doi.org/10.1016/j.geoen.2023.211600
4. Coussy O., Poromechanics, Chichester: J.Wiley& Sons Ltd, 2004, 360 p., DOI: https://doi.org/10.1002/0470092718
5. Dontsov E., Peirce A.P., Comparison of toughness propagation criteria for blade-like and pseudo-3D hydraulic fractures, Eng. Fract. Mech., 2016, V. 160, pp. 238–247, DOI: https://doi.org/10.1016/j.engfracmech.2016.04.023
6. Kremenetskiy M.I., Ipatov A.I., Gidrodinamicheskie i promyslovo-tekhnologicheskie issledovaniya skvazhin (Hydrodynamic and oil field and technological research of wells), Moscow: MAKS Press Publ., 2008, 476 p.
7. Hecht F., New development in FreeFem++, J. Num. Math. Vol., 2012, V. 20, no. 3– 4, pp. 251–266.
