• Application of Vertically-Integrated Models with Subscale Vertical Dynamics to Field Sites for CO2 Sequestration 

      Guo, B; Bandilla, Karl W.; Keilegavlen, Eirik; Doster, Florian; Celia, Michael A. (Peer reviewed; Journal article, 2014)
      To address the engineering questions on security issues of geological carbon sequestration (GCS), a broad range of computational models with different levels of complexity have been developed - from multiphase multicomponent ...
    • Auxiliary variables for 3D multiscale simulations in heterogeneous porous media 

      Sandvin, Andreas; Keilegavlen, Eirik; Nordbotten, Jan Martin (Journal article, 2013-04-01)
      The multiscale control-volume methods for solving problems involving flow in porous media have gained much interest during the last decade. Recasting these methods in an algebraic framework allows one to consider them as ...
    • A combined finite element–finite volume framework for phase-field fracture 

      Sargado, Juan Michael Uy Villanueva; Keilegavlen, Eirik; Berre, Inga; Nordbotten, Jan Martin (Journal article; Peer reviewed, 2021)
      Numerical simulations of brittle fracture using phase-field approaches often employ a discrete approximation framework that applies the same order of interpolation for the displacement and phase-field variables. In particular, ...
    • Conforming, non-conforming and non-matching discretization couplings in discrete fracture network simulations 

      Fumagalli, Alessio; Keilegavlen, Eirik; Scialo, Stefano (Peer reviewed; Journal article, 2019)
      Simulations of fluid flow in naturally fractured rocks have implications for several subsurface applications, including energy storage and extraction, and waste disposal. We are interested in flow in discrete fracture ...
    • Consistent MPFA Discretization for Flow in the Presence of Gravity 

      Starnoni, Michele; Berre, Inga; Keilegavlen, Eirik; Nordbotten, Jan Martin (Peer reviewed; Journal article, 2019)
      A standard practice used in the industry to discretizing the gravity term in the two‐phase Darcy flow equations is to apply an upwind strategy. In this paper, we show that this can give a persistent unphysical flux field ...
    • Crustal Conditions Favoring Convective Downward Migration of Fractures in Deep Hydrothermal Systems 

      Halldorsdottir, Sæunn; Berre, Inga; Keilegavlen, Eirik; Axelsson, Gudni (Journal article; Peer reviewed, 2023)
      Cooling magma plutons and intrusions are the heat sources for hydrothermal systems in volcanic settings. To explain system longevity and observed heat transfer at rates higher than those explained by pure conduction, the ...
    • Domain decomposition preconditioning for non-linear elasticity problems 

      Keilegavlen, Eirik; Skogestad, Jan Ole; Nordbotten, Jan Martin (Chapter; Peer reviewed, 2014)
      We consider domain decomposition techniques for a non-linear elasticity problem. Our main focus is on non-linear preconditioning, realized in the framework of additive Schwarz preconditioned inexact Newton (ASPIN) methods. ...
    • Dual virtual element methods for discrete fracture matrix models 

      Fumagalli, Alessio; Keilegavlen, Eirik (Peer reviewed; Journal article, 2019)
      The accurate description of fluid flow and transport in fractured porous media is of paramount importance to capture the macroscopic behavior of an oil reservoir, a geothermal system, or a CO2 sequestration site, to name ...
    • Effective permeability of deformation bands in fault damage zones – Can deformation bands reduce the risk of fault leakage? 

      Berge, Runar Lie; Gasda, Sarah Eileen; Keilegavlen, Eirik; Sandve, Tor Harald (SINTEF Proceedings;7, Chapter, 2021)
      Faults are major geological structures that can dominate the flow paths in subsurface reservoirs by, e.g., connecting otherwise unconnected layers. In CO2 storage sites where the faults act as the main structural trap, the ...
    • Effective Preconditioners for Mixed-Dimensional Scalar Elliptic Problems 

      Hu, Xiaozhe; Keilegavlen, Eirik; Nordbotten, Jan Martin (Journal article; Peer reviewed, 2023)
      Discretization of flow in fractured porous media commonly lead to large systems of linear equations that require dedicated solvers. In this work, we develop an efficient linear solver and its practical implementation for ...
    • Field-case simulation of CO2-plume migration using vertical-equilibrium models 

      Nilsen, Halvor Møll; Herrera, Paulo; Ashraf, Seyed Meisam; Ligaard, Ingeborg S.; Iding, Martin; Hermanrud, Christian; Lie, Knut-Andreas; Nordbotten, Jan Martin; Dahle, Helge K.; Keilegavlen, Eirik (Peer reviewed; Journal article, 2011)
      When injected in deep saline aquifers, CO2 moves radially away from the injection well and progressively higher in the formation because of buoyancy forces. Analyzes have shown that after the injection period, CO2 will ...
    • Finite volume discretization for poroelastic media with fractures modeled by contact mechanics 

      Berge, Runar Lie; Berre, Inga; Keilegavlen, Eirik; Nordbotten, Jan Martin; Wohlmuth, Barbara (Peer reviewed; Journal article, 2020)
      A fractured poroelastic body is considered where the opening of the fractures is governed by a nonpenetration law, whereas slip is described by a Coulomb‐type friction law. This physical model results in a nonlinear ...
    • Finite volume methods for elasticity with weak symmetry 

      Keilegavlen, Eirik; Nordbotten, Jan Martin (Peer reviewed; Journal article, 2017-11)
      We introduce a new cell‐centered finite volume discretization for elasticity with weakly enforced symmetry of the stress tensor. The method is motivated by the need for robust discretization methods for deformation and ...
    • A Finite-Volume-Based Module for Unsaturated Poroelasticity 

      Varela, Jhabriel; Gasda, Sarah Eileen; Keilegavlen, Eirik; Nordbotten, Jan Martin (Chapter, 2021)
      In this chapter, we present fv-unsat, a multipoint finite-volume–based solver for unsaturated flow in deformable and nondeformable porous media. The latter is described using the mixed form of Richards’ equation, whereas ...
    • Flexible and rigorous numerical modelling of multiphysics processes in fractured porous media using PorePy 

      Stefansson, Ivar; Varela, Jhabriel; Keilegavlen, Eirik; Berre, Inga (Journal article; Peer reviewed, 2024)
      Multiphysics processes in fractured porous media is a research field of importance for several subsurface applications and has received considerable attention over the last decade. The dynamics are characterized by strong ...
    • Flow in Fractured Porous Media: A Review of Conceptual Models and Discretization Approaches 

      Berre, Inga; Doster, Florian; Keilegavlen, Eirik (Peer reviewed; Journal article, 2019)
      The last decade has seen a strong increase of research into flows in fractured porous media, mainly related to subsurface processes but also in materials science and biological applications, as connected fractures can ...
    • Fractal structures in freezing brine 

      Alyaev, Sergey; Keilegavlen, Eirik; Nordbotten, Jan Martin; Pop, Iuliu Sorin (Peer reviewed; Journal article, 2017-09)
      The process of initial ice formation in brine is a highly complex problem. In this paper, we propose a mathematical model that captures the dynamics of nucleation and development of ice inclusions in brine. The primary ...
    • A fully coupled numerical model of thermo-hydro-mechanical processes and fracture contact mechanics in porous media 

      Stefansson, Ivar; Keilegavlen, Eirik; Berre, Inga (Journal article; Peer reviewed, 2021)
      Various phenomena in the subsurface are characterised by the interplay between deforming structures such as fractures and coupled thermal, hydraulic and mechanical processes. Simulation of subsurface dynamics can provide ...
    • High-accuracy phase-field models for brittle fracture based on a new family of degradation functions 

      Sargado, Juan Michael; Keilegavlen, Eirik; Berre, Inga; Nordbotten, Jan Martin (Peer reviewed; Journal article, 2018-02)
      Phase-field approaches to fracture based on energy minimization principles have been rapidly gaining popularity in recent years, and are particularly well-suited for simulating crack initiation and growth in complex fracture ...
    • Hydro-mechanical simulation and analysis of induced seismicity for a hydraulic stimulation test at the Reykjanes geothermal field, Iceland 

      Keilegavlen, Eirik; Duboeuf, Laure; Dichiarante, Anna Maria; Halldorsdottir, Sæunn; Stefansson, Ivar; Naumann, Marcel; Guðnason, Egill Árni; Ágústsson, Kristján; Eggertsson, Guðjón Helgi; Oye, Volker; Berre, Inga (Journal article; Peer reviewed, 2021)
      The combination of seismic analysis with advanced physics-based simulation provides an opportunity to further understand injection-induced fault reactivation, including the hydro-mechanical interplay between different ...