On heat and mass transfer within thermally shocked region of enhanced geothermal system

Kamran Jahan Bakhsh, Masami Nakagawa, Mahmood Arshad, Lucila Dunnington

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

An Enhanced Geothermal System (EGS) is an artificially created geothermal reservoir formed by hydrofracturing hot dry rock. Thermal shock occurs when the cold water contacts the hot rock near the injection borehole, creating a network of small, disorganized, closely spaced micro cracks. As the cold-water injection continues, the hot rock cools down and the micro cracks coalesce, becoming a better-defined network of thermal fractures. Thermal fractures in an EGS reservoir are believed to improve reservoir performance by increasing the surface area for heat exchange and lowering flow impedance; however, it is difficult to precisely predict how they grow and affect the permeability of the reservoir. The goal of this paper is to provide an insight into the transport mechanisms within the thin, permeable, thermally shocked region of an EGS reservoir. COMSOL Multiphysics® is used to set up an indealized porous region with identical geometrical features at different domain scales to show the scale dependence of heat and mass transport in the initial microscale crack network and in the later coalesced thermal fractures. This research shows the importance of EGS maturity in determining how heat and mass are transferred and how to select appropriate analytical tools for different stages of development.

Original languageEnglish
Article number2759267
JournalGeofluids
Volume2017
DOIs
Publication statusPublished - Jan 1 2017
Externally publishedYes

Fingerprint

heat transfer
mass transfer
microcrack
cold water
hot dry rock
mass transport
rock
crack
borehole
surface area
enhanced geothermal system
permeability

All Science Journal Classification (ASJC) codes

  • Earth and Planetary Sciences(all)

Cite this

On heat and mass transfer within thermally shocked region of enhanced geothermal system. / Bakhsh, Kamran Jahan; Nakagawa, Masami; Arshad, Mahmood; Dunnington, Lucila.

In: Geofluids, Vol. 2017, 2759267, 01.01.2017.

Research output: Contribution to journalArticle

Bakhsh, Kamran Jahan ; Nakagawa, Masami ; Arshad, Mahmood ; Dunnington, Lucila. / On heat and mass transfer within thermally shocked region of enhanced geothermal system. In: Geofluids. 2017 ; Vol. 2017.
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