Ivar Stefansson er en forsker i gruppen for porøse medier og Senter for modellering av koblet undergrunnsdynamikk ved Matematisk institutt. Han forsker på utvikling av numeriske metoder og simuleringsteknologi for porøse medier med sprekker. Disse metodene hjelper oss å forstå prosesser i undergrunnen, for eksempel knyttet til geotermisk energi. Ivar er en av hovedutviklerne av simuleringsverktøyet PorePy.

Vitenskapelig foredrag

• Berre, Inga; Both, Jakub Wiktor; Halldorsdottir, Sæunn et al. (2024). Mathematical and Numerical Modelling of Process-Structure Interaction in FracturedGeothermal Systems. (ekstern lenke)
• Jacobsen, Ingrid Kristine; Berre, Inga; Nordbotten, Jan Martin et al. (2024). An MPSA-Newmark discretization of the elastic wave equation with absorbing boundary conditions. (ekstern lenke)
• Berre, Inga; Banshoya, Shin Irgens; Stefansson, Ivar et al. (2024). Simulation of THMC processes in fractured porous media . (ekstern lenke)
• Stefansson, Ivar (2024). A simple and efficient line search for nonlinear and semismooth multiphysics problems . (ekstern lenke)
• Berre, Inga; Stefansson, Ivar (2024). Process-structure interaction in geothermal reservoirs: modeling and simulation. (ekstern lenke)
• Stefansson, Ivar; Keilegavlen, Eirik; Both, Jakub Wiktor et al. (2024). Multiphysics simulation of fractured geothermal systems using PorePy. (ekstern lenke)
• Stefansson, Ivar (2023). Elastic normal fracture deformation ​ in thermoporomechanical media. (ekstern lenke)
• Stefansson, Ivar (2023). Modeling and Simulation of Fracture Deformation in Coupled Problems. (ekstern lenke)
• Keilegavlen, Eirik; Banshoya, Shin Irgens; Halldorsdottir, Sæunn et al. (2022). Modeling and Simulation of Thermo-Hydro-Mechanical-Chemical Processes in Fractured Rocks with Applications to Geothermal Energy. (ekstern lenke)
• Stefansson, Ivar; Rinaldi, Antonio; Driesner, Thomas et al. (2022). Mixed-dimensional hydromechanical modelling of an in situ hydroshearing experiment. (ekstern lenke)
• Halldorsdottir, Sæunn; Berre, Inga; Keilegavlen, Eirik et al. (2021). Thermal fracturing and natural convection: A hidden source of geothermal activity in the earth’s crust?. (ekstern lenke)
• Berre, Inga; Ervik, Haakon Langeland; Stefansson, Ivar et al. (2021). Discrete Fracture-Matrix Modelling of Coupled THM Processes and Fracture Deformation. (ekstern lenke)
• Keilegavlen, Eirik; Stefansson, Ivar; Berre, Inga et al. (2020). A simulation model for fracture reactivation accounting for thermo-hydro-mechanical forces with applications to geothermal systems. (ekstern lenke)
• Berre, Inga; Berge, Runar Lie; Dang, Hau Trung et al. (2020). Modelling of process-structure interaction resulting from fluid injection in fractured subsurface systems. (ekstern lenke)
• Stefansson, Ivar; Berre, Inga; Fumagalli, Alessio et al. (2019). Numerical Methods for Flow in Fractured Porous Media in a Unified Implementation. (ekstern lenke)
• Keilegavlen, Eirik; Stefansson, Ivar; Berre, Inga et al. (2019). Enhancing Geothermal Reservoirs – Modelling and Analysis of Hydraulic and Thermal Stimulation. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Stefansson, Ivar et al. (2019). Mixed-dimensional discrete fracture matrix models with heterogeneous discretization and non-matching grids. (ekstern lenke)
• Stefansson, Ivar; Berre, Inga; Keilegavlen, Eirik et al. (2018). Modelling of thermal shock induced fracture growth. (ekstern lenke)
• Berge, Runar Lie; Keilegavlen, Eirik; Fumagalli, Alessio et al. (2018). PorePy: A Python Simulation Tool for Fractured and Deformable Porous Media​. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Stefansson, Ivar et al. (2018). Unified modeling and discretization of flow in fractured porous media. (ekstern lenke)
• Berre, Inga; Flemisch, Bernd; Scotti, Anna et al. (2017). [2] Benchmarking and comparison of numerical methods: overall considerations and a recent study of methods for flow in fractured porous media, Flow in Deformable Porous Media: Numerics and Benchmarks. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Berge, Runar Lie et al. (2017). PorePy: A Python Simulation Tool for Fractured and Deformable Porous Media. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Berge, Runar Lie et al. (2017). Discretization of mixed-dimensional problems using legacy codes. (ekstern lenke)
• Stefansson, Ivar; Berre, Inga; Keilegavlen, Eirik (2017). Handling of Fractures and Intersections in Finite Volume Methods. (ekstern lenke)

Poster

• Berre, Inga; Stefansson, Ivar (2024). Multi-Point Finite Volume Method for Fracture Propagation in Linear Elastic Media. (ekstern lenke)
• Berre, Inga; Stefansson, Ivar (2024). Multi-Point Finite Volume Method for Fracture Propagation in Linear Elastic Media. (ekstern lenke)
• Stefansson, Ivar; Berre, Inga; Keilegavlen, Eirik (2019). Simulation of temperature and pressure driven fracture deformation. (ekstern lenke)
• Stefansson, Ivar; Keilegavlen, Eirik; Berre, Inga (2017). Coupling Conditions for Finite Volume Methods for Fractured Porous Media. (ekstern lenke)
• Stefansson, Ivar; Berre, Inga; Keilegavlen, Eirik (2017). Finite Volume Methods for Flow and Transport in 3-Dimensional Fractured Porous Media. (ekstern lenke)

Populærvitenskapelig artikkel

• Jacobsen, Ingrid Kristine; Nevland, Marius; Stefansson, Ivar (2024). Geotermisk energi. (ekstern lenke)
• Stefansson, Ivar (2022). Slik kan vi hente stabil, fornybar energi fra under bakken. (ekstern lenke)
• Stefansson, Ivar (2022). Slik kan vi hente stabil, fornybar energi fra under bakken. (ekstern lenke)
• Stefansson, Ivar (2019). Geotermisk energiproduksjon. (ekstern lenke)

Faglig foredrag

• Stefansson, Ivar; Nermoen, Anders; Wheeler, Walter H et al. (2024). Ground source heat in Norway – on the value gained by firm, renewable, carbon neutral, local and areal effective thermal resources by the Geothermal Energy Association of Norway. (ekstern lenke)
• Nermoen, Anders; Iversen, Fionn; Stefansson, Ivar (2023). Network Meeting Bergen: Ground Source Heat Pump Energy System . (ekstern lenke)
• Nermoen, Anders; Pelfrene, Gilles; Iversen, Fionn et al. (2023). GeoEnergy 2023. (ekstern lenke)
• Stefansson, Ivar; Berre, Inga; Keilegavlen, Eirik (2017). Coupled processes in geothermal systems. (ekstern lenke)

Vitenskapelig artikkel

• Stefansson, Ivar (2024). A line search algorithm for multiphysics problems with fracture deformation. (ekstern lenke)
• Stefansson, Ivar; Varela, Jhabriel; Keilegavlen, Eirik et al. (2024). Flexible and rigorous numerical modelling of multiphysics processes in fractured porous media using PorePy. (ekstern lenke)
• Stefansson, Ivar; Keilegavlen, Eirik (2023). Numerical Treatment of State-Dependent Permeability in Multiphysics Problems. (ekstern lenke)
• Berre, Inga; Boon, Wietse; Flemisch, Bernd et al. (2021). Verification benchmarks for single-phase flow in three-dimensional fractured porous media. (ekstern lenke)
• Keilegavlen, Eirik; Berge, Runar Lie; Fumagalli, Alessio et al. (2021). PorePy: an open-source software for simulation of multiphysics processes in fractured porous media. (ekstern lenke)
• Stefansson, Ivar; Keilegavlen, Eirik; Berre, Inga (2021). A fully coupled numerical model of thermo-hydro-mechanical processes and fracture contact mechanics in porous media. (ekstern lenke)
• Keilegavlen, Eirik; Duboeuf, Laure; Dichiarante, Anna Maria et al. (2021). Hydro-mechanical simulation and analysis of induced seismicity for a hydraulic stimulation test at the Reykjanes geothermal field, Iceland. (ekstern lenke)
• Stefansson, Ivar; Keilegavlen, Eirik; Halldorsdottir, Sæunn et al. (2021). Numerical Modelling of Convection-Driven Cooling, Deformation and Fracturing of Thermo-Poroelastic Media. (ekstern lenke)
• Berre, Inga; Stefansson, Ivar; Keilegavlen, Eirik (2020). Fault slip in hydraulic stimulation of geothermal reservoirs: Governing mechanisms and process-structure interaction. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Berge, Runar Lie et al. (2019). Implementation of mixed-dimensional models for flow in fractured porous media. (ekstern lenke)
• Stefansson, Ivar; Berre, Inga; Keilegavlen, Eirik (2018). Finite-volume discretisations for flow in fractured porous media. (ekstern lenke)
• Flemisch, Bernd; Berre, Inga; Boon, Wietse et al. (2018). Benchmarks for single-phase flow in fractured porous media. (ekstern lenke)

Populærvitenskapelig foredrag

• Stefansson, Ivar (2024). Some whys and hows of computational mathematics. (ekstern lenke)

Programvare

• Keilegavlen, Eirik; Stefansson, Ivar; Duran, Omar et al. (2023). PorePy: A Simulation Tool for Fractured and Deformable Porous Media, version 1.8.1. (ekstern lenke)
• Keilegavlen, Eirik; Stefansson, Ivar; Varela, Jhabriel et al. (2021). PorePy versjon 1.5 (simuleringsverktøy for prosesser i oppsprukne porøse medier). (ekstern lenke)
• Stefansson, Ivar; Keilegavlen, Eirik; Berge, Runar Lie et al. (2020). PorePy: Python Simulation Tool for Fractured and Deformable Porous Media. Versjon 1.3. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Berge, Runar Lie et al. (2019). PorePy: A Simulation Tool for Fractured and Deformable Porous Media written in Python, v.1.0. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Berge, Runar Lie et al. (2018). PorePy: A Simulation Tool for Fractured and Deformable Porous Media written in Python, versjon 0.4.3. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Berge, Runar Lie et al. (2017). PorePy: A Simulation Tool for Fractured and Deformable Porous Media written in Python. (ekstern lenke)
• Keilegavlen, Eirik; Fumagalli, Alessio; Berge, Runar Lie et al. (2017). PorePy: A Python Simulation Tool for Fractured and Deformable Porous Media. Version 0.2. (ekstern lenke)

Dokumentar

• Nordbotten, Jan Martin; Berge, Runar Lie; Stefansson, Ivar (2022). Runar Lie Berge - Numerical methods for coupled processes in fractured porous media. (ekstern lenke)
• Nordbotten, Jan Martin; Budisa, Ana; Stefansson, Ivar (2022). Ana Budiša - Preconditioning for Flow in Fractured Porous Media. (ekstern lenke)

Vitenskapelig Kapittel/Artikkel/Konferanseartikkel

• Stefansson, Ivar; Berge, Runar Lie; Berre, Inga et al. (2021). Modelling of Thermally Induced Fracture Slip caused by Fluid Injection During Geothermal Production. (ekstern lenke)
• Stefansson, Ivar; Berre, Inga; Keilegavlen, Eirik (2020). Finite Volume Discretisation of Fracture Deformation in Thermo-poroelastic Media. (ekstern lenke)

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