GEOTHERMAL TECHNOLOGIES LEGACY COLLECTION - Bibliographic Citation


Bibliographic Citation


Full Text:
application/pdf
0 K

View Full Text Access Individual Pages  -   Search, view and/or download individual pages
Title: THERMO-HYDRO-MECHANICAL MODELING OF WORKING FLUID INJECTION AND THERMAL ENERGY EXTRACTION IN EGS FRACTURES AND ROCK MATRIX
Creator/Author: Robert Podgorney ; Chuan Lu ; Hai Huang
Publication Date:2012 Jan 01
OSTI Identifier:OSTI 1042378
Report Number(s):INL/CON-12-24584
DOE Contract Number:DE-AC07-05ID14517
Document Type:Conference
Specific Type:
Coverage:
Resource Relation:Conference: Stanford Geothermal Workshop,Stanford,01/29/2012,02/01/2012
Other Number(s):
Research Org:Idaho National Laboratory (INL)
Sponsoring Org:DOE - EE
Subject:15 GEOTHERMAL ENERGY; COUPLING; DEFORMATION; ENTHALPY; EXTRACTION; FLUID FLOW; FRACTURES; FRACTURING; GEOTHERMAL SYSTEMS; HEAT; HEAT TRANSFER; INJECTION; PARTIAL DIFFERENTIAL EQUATIONS; PERFORMANCE; PERMEABILITY; PRODUCTION; RESERVOIR ROCK; ROCK MECHANICS; ROCKS; SHEAR; SIMULATION; SIMULATORS; SOLIDS; SOLUTIONS; STIMULATION; TRANSPORT; VOLUME; WORKING FLUIDS
Keywords:egs; geothermal; modeling
Description/Abstract:Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing), to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid-heat system and our ability to reliably predict how reservoirs behave under stimulation and production. Reliable performance predictions of EGS reservoirs require accurate and robust modeling for strongly coupled thermal-hydrological-mechanical (THM) processes. Conventionally, these types of problems have been solved using operator-splitting methods, usually by coupling a subsurface flow and heat transport simulators with a solid mechanics simulator via input files. An alternative approach is to solve the system of nonlinear partial differential equations that govern multiphase fluid flow, heat transport, and rock mechanics simultaneously, using a fully coupled, fully implicit solution procedure, in which all solution variables (pressure, enthalpy, and rock displacement fields) are solved simultaneously. This paper describes numerical simulations used to investigate the poro- and thermal- elastic effects of working fluid injection and thermal energy extraction on the properties of the fractures and rock matrix of a hypothetical EGS reservoir, using a novel simulation software FALCON (Podgorney et al., 2011), a finite element based simulator solving fully coupled multiphase fluid flow, heat transport, rock deformation, and fracturing using a global implicit approach. Investigations are also conducted on how these poro- and thermal-elastic effects are related to fracture permeability evolution.
Publisher:
Country of Publication:US
Language:English
Size/Format:Medium: ED
Rights:
Availability:
System Entry Date:2012 Dec 05
 View Non-Empty Fields Only

Top

Some links on this page may take you to non-federal websites. Their policies may differ from this site.