Coupled Flow and Geomechanics Simulation in Production Management
Abstract
Pressure drawdown management plays a key technical role in reservoir management as it has an important impact on the estimated ultimate recovery (EUR) and, consequently, on the cash flow and economic viability. Thus, careful pressure depletion management, which controls production through choke management, can be used to attain maximal net present value. A frequently used current strategy is to use the largest available choke size and to maximize the production in order to recover the capital expenses as early as possible. However, there is evidence from a number of field production data that maximal production and estimated recovery can be accomplished by limiting the early production, a strategy that appears to increase recovery and long-term production.
This study aims to evaluate alternative drawdown management strategies for a specific reservoir in an effort to identify production strategies that maximize present-day and long-term production and ultimate recovery without geomechanically compromising the integrity of the hydraulic fracture (HF) by following strategies that may result in reduction of the HF aperture and productivity/performance because of adverse stress conditions.
The study has two components. The first component involves an analysis of field data from a reservoir of interest in an effort to identify possible correlations of production drawdown performance and choke setting during flowback. I estimate the flowing bottomhole pressure from the production rate, the surface pressure and the wellbore description, and I conduct a rate transient analysis in order to assess the properties and attributes of the reservoir and the fractures.
The second component of the study involves the analysis of a number of choke management and production practices associated with bottomhole pressure control. This is accomplished by means of numerical simulation of the coupled flow and geomechanical processes that are involved in the course of the production of reservoir fluids from hydraulically fractured shale oil reservoirs. For the needs of the project, (a) I developed a fully implicit, non-isothermal three-phase, three component compositional simulator to estimate production from a 3D shale oil multi-fractured horizontal well system and (b) I coupled the flow simulator with a pre-existing, validated 3D geomechanical model (based on the fixed-stress method) using a sequential implicit scheme. The two-way coupling of the flow and geomechanical simulators allowed the accurate description of the interdependence between the flow conditions and properties (pressure, phase saturation, porosity and permeability) and the geomechanical attributes (stresses, strains and displacements) in the course of the production. I used the numerical simulator to investigate the evolution of pressure, porosity, displacements and volumetric strains in the matrix and the fracture system under different pressure drawdown strategies. The estimated ultimate recovery is the criterion used for the evaluation of the various choke management strategies.
Subject
Coupled flow and geomechanics simulationProduction Management
Rate Transient Analysis
History Matching
Citation
Jin, Kejun (2020). Coupled Flow and Geomechanics Simulation in Production Management. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /200776.