A Numerical Model Coupling Reservoir and Horizontal Well Flow Dynamics—Applications in Well Completions, and Production Logging

A fully implicit, three-dimensional simulator with local grid refinement around the wellbore is developed to solve reservoir and horizontal well flow equations simultaneously, for single-phase liquid and gas cases. The model consists of conservation of mass and Darcy's law in the reservoir, and mass and momentum conservation in the wellbore for isothermal conditions. Establishing the continuity of pressure and preserving mass balance at the sandface satisfy the coupling requirements. The proposed simulator is tested against and verified with the results obtained from a commercial code ECLIPSE-100, and available public domain simulators and semi-analytical models. The proposed model can be used for multiple purposes such as well productivity prediction, transient analyses, well length optimization, completion design and optimization, and production logging interpretation. Different completion scenarios and reservoir anisotropy are simulated and their effects on the productivity of the horizontal wells are discussed. Completion cases include open-hole and partial completions. During the production logging of a horizontal well, the coil tubing reduces the wellbore cross sectional area and may cause substantial changes in the wellbore flow behavior. Depending on the well and coil tubing diameters, a significant difference between the actual production rates and the rates obtained from a production log can be observed.

[1]  Cem Sarica,et al.  An Investigation of Horizontal Well Completions Using a Two-Phase Model Coupling Reservoir and Horizontal Well Flow Dynamics , 2001 .

[2]  D. W. Peaceman.  Representation Of A Horizontal Well In Numerical Reservoir Simulation , 1993 .

[3]  Erdal Ozkan,et al.  Interpretation of Horizontal-Well Production Logs: Influence of Logging Tool , 1998 .

[4]  James P. Brill,et al.  Effect of Perforation Density on Single Phase Liquid Flow Behavior in Horizontal Wells , 1996 .

[5]  C. Sarica,et al.  Influence of Pressure Drop Along the Wellbore on Horizontal-Well Productivity , 1999 .

[6]  Michael J. Landman,et al.  Analytic modelling of selectively perforated horizontal wells , 1994 .

[7]  Ole Harald Utvik,et al.  Pressure Drop in a Perforated Pipe With Radial Inflow: Single-Phase Flow , 1998 .

[8]  D. W. Peaceman.  Interpretation of well-block pressures in numerical reservoir simulation with nonsquare grid blocks and anisotropic permeability , 1983 .

[9]  T. S. Daltaban,et al.  Fundamental and applied pressure analysis , 1998 .

[10]  Ura Cnrs,et al.  On the initial value problem for a linear model of well- reservoir coupling , 1996 .

[11]  T. Ertekin,et al.  Implementation of a local grid refinement technique in modeling slanted, undulating horizontal and multi-lateral wells , 1999 .

[12]  William H. Press,et al.  Numerical recipes , 1990 .

[13]  Mohan Kelkar,et al.  Performance of Horizontal Wells Completed with Slotted Liners and Perforations , 2000 .