Thermal Drawdown Induced Flow Channeling in Fractured Geothermal Reservoirs: Rock Mechanics and Rock Engineering
We investigate the flow-channeling phenomenon caused by thermal drawdown in fractured geothermal reservoirs. A discrete fracture network-based, fully coupled thermal "hydrological" mechanical simulator is used to study the interactions between fluid flow, temperature change, and the associated rock deformation. The responses of a number of randomly generated 2D fracture networks that represent a variety of reservoir characteristics are simulated with various injection-production well distances. We find that flow channeling, namely flow concentration in cooled zones, is the inevitable fate of all the scenarios evaluated. We also identify a secondary geomechanical mechanism caused by the anisotropy in thermal stress that counteracts the primary mechanism of flow channeling. This new mechanism tends, to some extent, to result in a more diffuse flow distribution, although it is generally not strong enough to completely reverse flow channeling. We find that fracture intensity substantially affects the overall hydraulic impedance of the reservoir but increasing fracture intensity generally does not improve heat production performance. Increasing the injection-production well separation appears to be an effective means to prolong the production life of a reservoir.
DOI: 10.1007/s00603-015-0776-0.
RMRE Peer Review Paper.pdf
Citation Formats
TY - DATA
AB - We investigate the flow-channeling phenomenon caused by thermal drawdown in fractured geothermal reservoirs. A discrete fracture network-based, fully coupled thermal "hydrological" mechanical simulator is used to study the interactions between fluid flow, temperature change, and the associated rock deformation. The responses of a number of randomly generated 2D fracture networks that represent a variety of reservoir characteristics are simulated with various injection-production well distances. We find that flow channeling, namely flow concentration in cooled zones, is the inevitable fate of all the scenarios evaluated. We also identify a secondary geomechanical mechanism caused by the anisotropy in thermal stress that counteracts the primary mechanism of flow channeling. This new mechanism tends, to some extent, to result in a more diffuse flow distribution, although it is generally not strong enough to completely reverse flow channeling. We find that fracture intensity substantially affects the overall hydraulic impedance of the reservoir but increasing fracture intensity generally does not improve heat production performance. Increasing the injection-production well separation appears to be an effective means to prolong the production life of a reservoir.
DOI: 10.1007/s00603-015-0776-0.
AU - Fu, Pengcheng
A2 - Carrigan, Charles R.
A3 - Walsh, Stuart D. C.
A4 - Hao, Yue
DB - Open Energy Data Initiative (OEDI)
DP - Open EI | National Renewable Energy Laboratory
DO -
KW - geothermal
KW - thermal drawdown
KW - flow channeling
KW - thermomechanical coupling
KW - reservoir simulation
KW - stimulation
KW - egs
KW - enhanced geothermal reservoirs
KW - explosive fracturing
LA - English
DA - 2015/11/15
PY - 2015
PB - Lawrence Livermore National Laboratory
T1 - Thermal Drawdown Induced Flow Channeling in Fractured Geothermal Reservoirs: Rock Mechanics and Rock Engineering
UR - https://data.openei.org/submissions/6890
ER -
Fu, Pengcheng, et al. Thermal Drawdown Induced Flow Channeling in Fractured Geothermal Reservoirs: Rock Mechanics and Rock Engineering. Lawrence Livermore National Laboratory, 15 November, 2015, GDR. https://gdr.openei.org/submissions/654.
Fu, P., Carrigan, C., Walsh, S., & Hao, Y. (2015). Thermal Drawdown Induced Flow Channeling in Fractured Geothermal Reservoirs: Rock Mechanics and Rock Engineering. [Data set]. GDR. Lawrence Livermore National Laboratory. https://gdr.openei.org/submissions/654
Fu, Pengcheng, Charles R. Carrigan, Stuart D. C. Walsh, and Yue Hao. Thermal Drawdown Induced Flow Channeling in Fractured Geothermal Reservoirs: Rock Mechanics and Rock Engineering. Lawrence Livermore National Laboratory, November, 15, 2015. Distributed by GDR. https://gdr.openei.org/submissions/654
@misc{OEDI_Dataset_6890,
title = {Thermal Drawdown Induced Flow Channeling in Fractured Geothermal Reservoirs: Rock Mechanics and Rock Engineering},
author = {Fu, Pengcheng and Carrigan, Charles R. and Walsh, Stuart D. C. and Hao, Yue},
abstractNote = {We investigate the flow-channeling phenomenon caused by thermal drawdown in fractured geothermal reservoirs. A discrete fracture network-based, fully coupled thermal "hydrological" mechanical simulator is used to study the interactions between fluid flow, temperature change, and the associated rock deformation. The responses of a number of randomly generated 2D fracture networks that represent a variety of reservoir characteristics are simulated with various injection-production well distances. We find that flow channeling, namely flow concentration in cooled zones, is the inevitable fate of all the scenarios evaluated. We also identify a secondary geomechanical mechanism caused by the anisotropy in thermal stress that counteracts the primary mechanism of flow channeling. This new mechanism tends, to some extent, to result in a more diffuse flow distribution, although it is generally not strong enough to completely reverse flow channeling. We find that fracture intensity substantially affects the overall hydraulic impedance of the reservoir but increasing fracture intensity generally does not improve heat production performance. Increasing the injection-production well separation appears to be an effective means to prolong the production life of a reservoir.
DOI: 10.1007/s00603-015-0776-0.
},
url = {https://gdr.openei.org/submissions/654},
year = {2015},
howpublished = {GDR, Lawrence Livermore National Laboratory, https://gdr.openei.org/submissions/654},
note = {Accessed: 2025-05-17}
}
Details
Data from Nov 15, 2015
Last updated Aug 11, 2017
Submitted Nov 26, 2015
Organization
Lawrence Livermore National Laboratory
Contact
Authors
Original Source
https://gdr.openei.org/submissions/654Research Areas
Keywords
geothermal, thermal drawdown, flow channeling, thermomechanical coupling, reservoir simulation, stimulation, egs, enhanced geothermal reservoirs, explosive fracturingDOE Project Details
Project Name Validation of EGS Feasibility and Explosive Fracturing Techniques
Project Lead Elisabet Metcalfe
Project Number FY15 AOP 1.3.2.4
