TOUGH-UDEC: A simulator for coupled multiphase fluid flows, heat transfers and discontinuous deformations in fractured porous media

Journal Article · Wed Feb 13 00:00:00 EST 2019 · Computers and Geosciences

DOI:https://doi.org/10.1016/j.cageo.2019.02.004· OSTI ID:1542400

Lee, Jaewon ^[1]; Kim, Kwang-Il ^[2]; Min, Ki-Bok ^[2]; Rutqvist, Jonny ^[3]

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1. Korea Atomic Energy Research Inst., Daejeon (Korea, Republic of)
2. Seoul National Univ. (Korea, Republic of)
3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

A numerical simulator entitled TOUGH-UDEC is presented for the assessment of coupled thermal-hydraulic-mechanical processes in fractured porous media. Two existing well-established codes, TOUGH2 and UDEC, are coupled to model multiphase fluid flows, heat transfers, and discontinuous deformations in fractured porous media by means of discrete fracture representation. TOUGH2 is widely used for the modeling of heat transfers and multiphase multicomponent fluid flows, and UDEC is a well-known distinct element code for rock mechanics. The two codes are solved sequentially, with coupling parameters passed to each equation at specific intervals. After solving thermal-hydraulic equations within the TOUGH2 code, pressure and temperature information is imported into the UDEC model. Upon solving the mechanical equation within the UDEC code the calculated fracture apertures are converted to the equivalent permeability and porosity values for a TOUGH2 flow analysis. The solution is calculated by iteratively following an explicit sequence for numerical efficiency. Verifications are presented to demonstrate the capabilities of the coupled TOUGH-UDEC simulator. Three application examples of (1) shear dilation due to increased pore pressure, (2) thermal stress and (3) CO₂ injection, show that the new simulator can be an effective tool for geoengineering applications involving shear activation of fractures and faults.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC); National Research Foundation of Korea (NRF)
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1542400
• Journal Information: Computers and Geosciences, Vol. 126, Issue C; ISSN 0098-3004
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
Thermal-hydraulic-mechanical coupling simulator
Shear slip
Distinct element method