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Oil inflow to the production well is influenced by the permeability of the rock in a near-wellbore zone. Geomechanical properties of the rock are one of the factors determining permeability. As a result of elastoplastic deformations of the rock during the development of the field, the structure of the pore space changes, the permeability of the rock of the near-wellbore zone decreases, which leads to a decrease in the rate of the production well. The wave action of elastic vibrations on the near-wellbore zone is able to restore the permeability of the rock due to the elastic deformation of the rock matrix saturated with the formation fluid. The paper studies the laws of propagation of longitudinal and transverse waves in a saturated porous medium. An example of a permeable piston type tool is provided. When the maximum diameter is reached, the tool transfers elastic energy to the rock matrix (homogeneous at micro and macro levels). An analysis of the Bio equations is performed to estimate the penetration depth of elastic vibrations into the formation. It is shown that the penetration depth depends on the physical and mechanical properties of the rock and saturating fluid, as well as on the parameters of the elastic wave treatment. It is argued that the production well flow rate in the case of a flat-radial inflow of a single-phase fluid depends on the frequency. A technique (mathematical model) for changing the flow rate of a well as a result of the propagation of elastic vibrations (deformations) in a saturated porous medium is developed. To verify the methodology (mathematical model), the wave action was simulated in a vertical well using the finite element method (ABAQUS package). The depth of propagation of elastic vibrations is one meter from the well, which confirms the successful results of the wave action on formations with porosity from 15 to 21 % and permeability from 0.126 to 0.763 μm2 in wells of similar fields. The developed method can be used to assess the conduct of elastic wave treatment of wells in Perm region. References 1. Dyblenko V.P., Kamalov R.N., Shariffulin R.Ya., Tufanov I.A., Povyshenie produktivnosti i reanimatsiya skvazhin s primeneniem vibrovolnovogo vozdeystviya (Increasing productivity and reanimation of wells using vibrowave impact), Moscow: Nedra Publ., 2000, 381 p. 2. Gadiev S.M., Ispol'zovanie vibratsii v dobyche nefti (Using vibration in oil production), Moscow: Nedra Publ., 1977, 159 p. 3. Ryabokon' E.P., Laboratory study on the effect of elastic wave treatment on geomechanical and capillary properties of clastic reservoirs (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 4, pp. 54–57. 4. Biot M.A., Theory of propagation of elastic wave in a fluid saturated porous solid, Part I. Low frequency range, Journal of the Acoustical Society of America, 1956, V. 28, no. 2, pp. 168–178. 5. Tuncay K., Corapcioglu M.Y., Wave propagation in fractured porous media, Transport in Porous Media, 1996, no. 23, pp. 237–258. 6. Marfin E.A., Ovchinnikov M.N., Uprugie volny v nasyshchennykh poristykh sredakh (Elastic waves in saturated porous media), Kazan': Publ. of Kazan University, 2015, 31 p. 7. Nikolaevskiy V.N., Basniev K.S., Gorbunov A.T., Zotov G.A., Mekhanika nasyshchennykh poristykh sred (Mechanics of saturated porous media), Moscow: Nedra Publ., 1970, 339 p. 8. Zaslavskiy Yu.M., On excitation efficiency of the fast and slow Biot waves in water and gas saturated media (In Russ.), Tekhnicheskaya akustika, 2002, no. 2, pp. 1-12. 9. Biot M.A., Theory of propagation of elastic waves in a fluid-saturated porous solid, Part II. Higher frequency range, Journal of the Acoustical Society of America, 1956, V. 28, no. 2, pp. 179–191. 10. Suleymanov B.A., Abbasov E.M., Efendieva A.O., Vibrowave impact on the formation and bottomhole zone of wells, taking into account the slippage effect (In Russ.), Inzhenerno-fizicheskiy zhurnal = Journal of Engineering Physics and Thermophysics, 2008, V. 81, no. 2, pp. 100–113. 11. Johnson D. L., Koplin J., Dashen R., Theory of dynamic permeability and tortuosity in fluid saturated porous media, Journal of Fluid Mechanics, 1987, V. 176, pp. 379–402. 12. Prachkin V.G., Galyautdinov A.G., Wave technology stimulation of oil (In Russ.), Neftegazovoe delo, 2015, no. 5, pp. 215–235. |
