Numerical simulation of coupled flow dynamics in bottom-water reservoirs and horizontal wells

Horizontal wells are the primary method for developing bottom-water reservoirs. Accurately understanding the production contribution of each segment of a horizontal well and the downhole production performance serves as the basis for water control completion design. This understanding holds significant importance for enhancing well productivity, reducing costs, and improving efficiency. To address the deficiencies in the research on fluid flow in horizontal wells, ANYSY FLUENT is employed to analyze and evaluate influence rules and degree of target parameters-such as permeability distribution, production pressure difference, crude oil viscosity, and density-on the fluid in both the reservoir and the wellbore. The analysis reveal that the main locations of the reservoir and annulus distribution surface are near the toe of the wellbore. The number of diversion surfaces is correlated with permeability distribution, production pressure difference, crude oil viscosity, and crude oil density. Permeability distribution and oil viscosity play a dominant role: the number of distribution surface in the high-permeability heel section is significantly higher than that in the toe, and the number of distribution surface for crude oil with a viscosity of 200 cP is notably greater than that for 50 cP crude oil. The impacts of pressure drop and oil density are relatively minor: the number of distribution surface is the same under pressure differences of 1.5 MPa and 2.5 MPa, and the same holds true for crude oils with densities of 850 kg/m³ and 950 kg/m³. The research findings fills the gap in the study of fluid flow directions in horizontal wells and possess substantial scientific and engineering value for the effective development of bottom water reservoirs, as well as the production and management of horizontal wells.