Geomechanical response due to nonisothermal fluid injection into a reservoir. (July 2021)

• Record Type: Journal Article
• Authors: Green, Christopher P.; Wilkins, Andy; Ennis-King, Jonathan; LaForce, Tara
• Is Part Of: Advances in water resources. Volume 153(2021)
• Publication Date: 2021-07
• Subjects: Hydrology -- Periodicals; Hydrodynamics -- Periodicals; Hydraulic engineering -- Periodicals; 551.48
• DOI: 10.1016/j.advwatres.2021.103942
• Languages: English
• ISSNs: 0309-1708

Abstract

Highlights: Semi-analytical solutions to nonisothermal fluid injection are verified numerically. The numerical model allows adding features not possible in the analytic approach. Porosity evolution, capillarity, realistic fluid properties, etc, are explored. The additional features have minor impact on fluid and temperature evolution. The additional features have a major impact on displacements and stresses. The validated numerical model provides a demanding benchmark for other coupled codes. Abstract: The geomechanical response of a porous reservoir due to injection of fluid can result from a complex interplay between the changes in porepressure and temperature near the wellbore. As a result, predictions are usually made using either simplified analytical models, which may apply unrealistic assumptions in order to produce a tractable model, or detailed numerical simulations that can be computationally expensive. LaForce et al. (2014a, 2014b) developed a semi-analytical model for the geomechanical response of a reservoir to nonisothermal, multi-phase fluid injection, which has been used in studies of CO 2 sequestration. We demonstrate that a numerical solution using the MOOSE software precisely matches the analytical formulae. We then include various effects in the numerical model that relax the simplifying assumptions made in the analytical derivation. We find the analytic and numerical solutions for the fluid and temperature fronts still agree reasonably, while only qualitative agreement is observed for other quantities such as stress and displacement. We conclude the LaForce et al. (2014a, b) solutions are useful for rapid investigation of projects involving injection of cold fluid into warm aquifers. However, the enhancements afforded by MOOSE, such as high-precision fluid equations of state and the ability to more accurately capture geological complexity, along with its computational scalability which greatly reduces runtimes, means that MOOSE should be preferred for more sophisticated analyses. Because validating complex coupled codes is challenging, we propose that the model contained herein can be used as a benchmark for other coupled codes.