This study presents a numerical method of determining the sandface completion profile of a horizontal well to achieve a prescribed production objective. A technique is developed to determine the completion profile that maximizes an objective function (e.g., cumulative production) for a given well operating program in a defined reservoir environment. Sandface completion is modeled in terms of a connection factor between the reservoir gridblocks adjacent to the well and wellbore segments. Well performance is evaluated in terms of cumulative production within specified operational constraints (maximum rate, minimum bottomhole pressure). The method uses a finite-difference technique to determine the sensitivity of well performance to changes in the wellbore-reservoir connection profile. The optimum connection profile is determined by a gradient-based technique using the sensitivity coefficients from the finite-difference method. This approach can be used to either plan the sandface completion during the well design stage, or to optimize the completion after drilling based on measured petrophysical and flow properties of the formation. Examples are given in the paper covering both water-and gas-drive problems.

You can access this article if you purchase or spend a download.