Comprehensive Simulation of Horizontal-Well Performance

Abstract

The simulation of the performance of a horizontal well has generated certain new and important challenges. These include the partial penetration of the well in the horizontal direction within the allocated drainage area, the positioning of the well between the vertical boundaries, the distance from the parallel horizontal boundaries, and the permeability anisotropy. In addition, there are special problems in the simulation of the response of fractures (natural and induced) in regard to their contact with the well (longitudinal or transverse), their conductivity, and the conductivity distribution along the fracture.We developed new numerical techniques to facilitate the simulation of these diverse problems. We use a locally refined perpendicular bisection grid to describe the horizontal (or deviated) wellbore. The grid is strictly orthogonal for the anisotropic case, and wellbore blocks are almost regular octagonal prisms. The transition to the coarse Cartesian grid is also orthogonal. The fully implicit formulation ensures the stability of the numerical solution. Our results are found to be in excellent agreement with published analytical or semianalytical approximations. In addition, the results offer flexibility that is not possible with analytical solutions. The grid system used is particularly amenable to handling practical problems with real reservoir geometries and configurations.This paper presents a comprehensive numerical simulation of problems associated with horizontal wells, including the arbitrary positioning of the well within a fully anisotropic medium. Hydraulic or natural fractures that intersect the well in the longitudinal or transverse direction are simulated for both infinite and finite conductivities.

CFD-based representation of non-Newtonian polymer injectivity for a horizontal well with coupled formation-wellbore hydraulics

“…Babu and Odeh (1988) proposed (Chen and Asaad, 2005;Economides et al, 1991;Giger, 1985;Helmy and Wattenbarger, 1998;Joshi, 1986;Lu and Tiab, 2007;Mutalik and Godbole, 1988). A comprehensive review of productivity indexes was created by Choi et al (2008).…”

“…Horizontal wells have become increasingly popular in the oil industry, especially for thin reservoirs or reservoirs with relatively high vertical/horizontal permeability ratios (Economides et al, 1991). Horizontal wells increase the contact with the pay zone resulting in significantly higher production rates (Joshi, 1986), which is critical to the oil industry because oil discoveries have declined (Lake, 1989).…”

Recent Advances in Production Engineering

“…This configuration evolved into Joshi's (43) widely used equation, which accounted for vertical-to-horizontal permeability anisotropy. It was adjusted by Economides et al (44) for a wellbore in elliptical coordinates.…”

Prediction of Multistage Fracturing Performance in Horizontal Heavy Oil Carbonate Reservoir

“…These models use local grid refinement to explicitly represent the actual size of the fracture (Dowdle and Hyde 1977, Holditch 1979, Economides et al 1991. However, the requirement for small grid sizes to represent fractures exhausts computational power and cause serious stability limitations in multiphase flow (Ji et al 2004).…”