Abstract
In this paper we demonstrate the power of numerical simulation to match pressure data of complex horizontal wells of different types and reservoir heterogeneities. Analyzing large number of horizontal wells has shown that often there are cases that cannot be satisfactorily interpreted using analytical techniques. It requires more detailed investigation to handle several theoretical and practical challenges that are not normally encountered in analyzing vertical wells. The most important of these challenges are (1) the number of flow regimes in case of homogeneous infinite-acting reservoir, are 3 to 4 namely; early radial, linear, late radial and/or sometimes hemiradial and (2) the reservoir heterogeneity encountered while drilling horizontal wells (i.e. layering, faults/fractures, composite systems, …)
Finding the optimum grid settings necessary to model the flow regimes is by far the most critical aspect of the numerical simulation. Without an optimum grid, pressure response that represents numerical artifact, rather than physics of the problem, can be generated.
Three field cases are presented in this paper; a horizontal well intersecting a finite conductivity fracture, a horizontal power water injector well at the edge of the reservoir and a horizontal close to a finite conductivity fault. An integrated approach was used to match the pressure responses.
