High-Resolution Modeling and Visualization of Drained Rock Volume Around Hydraulically Fractured Wells in Heterogeneous Reservoirs
Abstract
This dissertation applies and further develops a new semi-analytical streamline simulator based on complex analysis methods (CAM) that enables high-resolution flow visualizations to identify the growth of the drained rock volume (DRV) in hydraulically fractured hydrocarbon reservoirs. This CAM tool is complementary to commonly used, computationally intensive finite-volume numerical reservoir simulators.
The dissertation is written in a journal style format following Texas A&M University guidelines, and comprises six papers, five of which have already been published. The coherence and innovations of the combined body of research is summarized in Chapter 1. Chapter 2 compares the effects on DRV when hydraulic fractures are simple planar hydraulic fractures or increasingly complex fractal networks. Chapter 3 introduces natural fracture heterogeneity impact on flow and DRV shape and location in the reservoir. Chapter 4 uses hydraulic fracture geo-mechanical propagation data to move from the 2D plane to 3D and create DRV envelope plots. Chapter 5 applies the developed methods to visualize the DRV and calculate recovery factors for Permian Basin wells. Chapter 6 presents new insight that industry should use convective tracer fronts for DRV (using CAM models) rather than pressure plots only, which are poor proxies for DRV in ultra-low permeability shale reservoirs. Chapter 7 presents initial results of ongoing research to compare CAM with the fast-marching-method (FMM). The final Chapter 8 gives conclusions and outlines avenues for future work.
Several innovative outcomes developed are:
(1) Integration of the Lindenmayer fractal algorithm with CAM to visualize DRV models for a variety of complex fracture networks (Ch.2).
(2) The development of a new upscaling method for flow in naturally fractured reservoirs by combining object-based and flow-based upscaling methods, which was applied to field data from the Hydraulic Fracturing Test Site (Ch.3).
(3) Creation of a new algorithm to compute pseudo-3D DRV envelopes around hydraulic fractures using imported hydraulic conductivity data generated with a commercial hydraulic fracture propagation simulator (Ch.4).
(4) A new approach to recovery factor calculations based on DRV plots (Ch.5).
(5) The quantification and visualization of the time lag between the diffusive pressure front and convective tracer front in unconventional reservoirs (Ch.6).
Subject
Reservoir ModelingDrained Rock Volume
Natural Fractures
Reservoir Simulation: Streamlines
Complex Analysis Method
Convective Time of Flight
Diffusive Time of Flight
Citation
Nandlal, Kiran (2020). High-Resolution Modeling and Visualization of Drained Rock Volume Around Hydraulically Fractured Wells in Heterogeneous Reservoirs. Doctoral dissertation, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /192424.