Inflow Performance for Slanted Wells in Anisotropic Reservoirs Considering Wellbore Pressure Drop

Abstract

The inflow performance prediction is very important to completion optimization of slanted wells. A reservoir/wellbore coupling model for slanted wells in anisotropic parallelepiped reservoirs considering wellbore pressure drop is presented based on source function method and superposition principle and solution methodology is described. On this basis, the inflow behavior of a slanted well in an anisotropic, infinite slab reservoir with impermeable top and bottom boundaries is investigated. Potential drop in the wellbore can cause flux difference, which is greatest under isotropic, and decreases with vertical anisotropy. Well productivity decreases with vertical anisotropy and the decrease is more significant for larger inclination angles than for smaller ones. Well inclination angle has a greater influence on inflow performance of wells in higher-anisotropy reservoirs than in lower-anisotropy ones and should be determined cautiously in the reservoir engineering design.