• Minimum entropy production in a distillation column for air separation described by a continuous non-equilibrium model 

      Kingston, Diego; Wilhelmsen, Øivind; Kjelstrup, Signe (Journal article; Peer reviewed, 2020)
      In this work, we apply the rate-based model of Taylor and Krishna to describe the separation of air in a low-pressure, packed distillation column. By use of numerical optimization, we identify the temperature profile for ...
    • Modelling of two-phase equilibrium, stability and steady-state flow in porous media 

      Gjennestad, Magnus Aashammer (Doctoral theses at NTNU;2020:364, Doctoral thesis, 2020)
      This thesis concerns fundamental aspects of coexistence and flow of two fluid phases within porous media. Specifically, the focus is on thermodynamic stability and equilibrium on the scale of a single pore and on macroscopic ...
    • Molecular alignment in molecular fluids induced by coupling between density and thermal gradients 

      Daub, Christopher David; Tafjord, Joakim; Kjelstrup, Signe; Bedeaux, Dick; Bresme, Fernando (Journal article; Peer reviewed, 2016)
      We investigate, using non-equilibrium molecular dynamics simulations and theory, the response of molecular fluids confined in slit pores under the influence of a thermal gradient and/or an applied force. The applied force ...
    • Molecular Dynamics Simulations of Metal / Molten Alkali Carbonate Interfaces 

      Roest, D.L.; Ballone, P.A.; Bedeaux, Dick; Kjelstrup, Signe (Journal article, 2017)
      Neutral and charged interfaces between molten alkali carbonates M2CO3 (M = Li, Na, and K) and planar solid walls have been investigated by molecular dynamics based on a rigid-ions force field. Simulations cover the temperature ...
    • Molecular Simulations of Gas Hydrates: Stability and Transport Properties 

      Waage, Magnus Heskestad (Doctoral theses at NTNU;2018:213, Doctoral thesis, 2018)
      At high pressures, mixtures of water and gas can form a crystalline compund called a gas hydrate. A considerable amount of methane hydrate exists at the sea floor and in permafrost regions. It is desirable to harvest this ...
    • Molten Carbonate Electrolyte Based Thermocell for High Temperature Waste Heat Recovery 

      Kandhasamy, Sathiyaraj (Doctoral theses at NTNU;2018:321, Doctoral thesis, 2019)
      Industrial processes for the production of metals and alloys by metallurgical and electrochemical methods generate a lot of waste heat due to irreversible losses. This waste heat could be used as a power source to produce ...
    • Nanothermodynamic Description and Molecular Simulation of a Single-Phase Fluid in a Slit Pore 

      Galteland, Olav; Bedeaux, Dick; Kjelstrup, Signe (Peer reviewed; Journal article, 2021)
      We have described for the first time the thermodynamic state of a highly confined single-phase and single-component fluid in a slit pore using Hill’s thermodynamics of small systems. Hill’s theory has been named ...
    • Nanothermodynamics and Molecular Simulations of Fluids in Porous Media 

      Galteland, Olav (Doctoral theses at NTNU;2022:144, Doctoral thesis, 2022)
      The thermodynamic and transport properties of fluids confined to porous media are in this thesis investigated with nanothermodynamics, non-equilibrium thermodynamics, and molecular simulations. Non-equilibrium thermodynamics ...
    • Nanothermodynamics of a Single-Phase Fluid Confined in a Complex Porous Medium 

      Varughese, Kevin Kottakkakathu (Master thesis, 2021)
      Nanotermodynamiske teorier og ideer blir her brukt på små systemer, spesifikt et porøsmedium, ved hjelp av Monte Carlo simulasjoner med Molekylær Dynamikk basert på "Grand Canonical Ensemble". Til å begynne med tester vi ...
    • Nature-inspired geometrical design of a chemical reactor 

      Magnanelli, Elisa; Solberg, Simon Birger Byremo; Kjelstrup, Signe (Journal article; Peer reviewed, 2019)
      We explore the possibility to actively use the system geometry to search for states of minimum entropy production in a chemical reactor. This idea is inspired by the energy-efficient mass and energy transfer that takes ...
    • Non-equilibrium Statistical Mechanics of Two-Phase Flow in Porous Media 

      Savani, Isha (Doctoral theses at NTNU;2016:335, Doctoral thesis, 2016)
      The world that we live in is a consortium of fluid-solid interactions. The field of two-phase flow in porous materials poses interesting questions regarding such interactions. In this project, we develop a statistical ...
    • Non-equilibrium thermodynamics and nature-inspired chemical engineering applied to PEM fuel cells 

      Sauermoser, Marco (Doctoral theses at NTNU;2021:38, Doctoral thesis, 2021)
      The first objective of this thesis is to discover potentials for the optimisation of the performance of polymer electrolyte membrane (PEM) fuel cells by using new designs for the flow field plates (FFP) based on nature-inspired ...
    • Non-equilibrium thermodynamics as a tool to compute temperature at the catalyst surface 

      Cruz, Carolina; Barragán, Daniel; Magnanelli, Elisa; Lervik, Anders; Kjelstrup, Signe (Journal article; Peer reviewed, 2019)
      The surface temperature is computed for a heterogeneous catalytic reaction model, namely the oxidation of carbon monoxide on platinum. The surface temperature was found using non-equilibrium thermodynamic theory, a theory ...
    • Non-isothermal transport of multi-phase fluids in porous media. Constitutive equations 

      Kjelstrup, Signe; Bedeaux, Dick; Hansen, Alex; Hafskjold, Bjørn; Galteland, Olav (Peer reviewed, Journal article, 2019)
      We define a representative elementary volume of a porous medium in terms of lumped extensive variables, including properties of homogeneous phases, interfaces, and contact lines. Using the grand potential, we define the ...
    • Non-isothermal transport of multi-phase fluids in porous media; The entropy production 

      Kjelstrup, Signe; Bedeaux, Dick; Hansen, Alex; Hafskjold, Bjørn; Galteland, Olav (Journal article; Peer reviewed, 2018)
      We derive the entropy production for transport of multi-phase fluids in a non-deformable, porous medium exposed to differences in pressure, temperature, and chemical potentials. Thermodynamic extensive variables on the ...
    • Nonequilibrium thermodynamics of surfaces captures the energy conversions in a shock wave 

      Hafskjold, Bjørn; Bedeaux, Dick; Kjelstrup, Signe; Wilhelmsen, Øivind (Peer reviewed; Journal article, 2020)
      A theory for the entropy production in a shock wave was developed using Gibbs’ excess properties in the framework of non-equilibrium thermodynamics (NET) of surfaces. The theory was used to analyze numerical results from ...
    • Numerical modelling of distinct ice lenses in frost heave 

      Ghoreishian Amiri, Seyed Ali; Grimstad, Gustav; Gao, Hao; Kjelstrup, Signe (Peer reviewed; Journal article, 2021)
      Frost heave happens when three conditions coincide: the temperature is below the normal freezing point of bulk water, the sub-cooled water is connected to a water reservoir, and the mechanical conditions of the soil allows ...
    • On the relation between the Langmuir and thermodynamic flux equations 

      van Erp, Titus Sebastiaan; Trinh, Thuat; Kjelstrup, Signe; Glavatskiy, Kirill (Journal article; Peer reviewed, 2014-01-22)
      Despite its approximative nature, the Langmuir theory has shown to be a very successful approach to describe experimental adsorption isotherms. Langmuir kinetics is based on systems of non-interacting particles that can ...
    • Onsager-symmetry obeyed in athermal mesoscopic systems: Two-phase flow in porous media 

      Winkler, Mathias; Gjennestad, Magnus Aashammer; Bedeaux, Dick; Kjelstrup, Signe; Cabriolu, Raffaela; Hansen, Alex (Peer reviewed; Journal article, 2020)
      We compute the fluid flow time correlation functions of incompressible, immiscible two-phase flow in porous media using a 2D network model. Given a properly chosen representative elementary volume, the flow rate distributions ...
    • Peltier effects in lithium-ion battery modeling 

      Spitthoff, Lena; Gunnarshaug, Astrid Fagertun; Bedeaux, Dick; Burheim, Odne Stokke; Kjelstrup, Signe (Peer reviewed; Journal article, 2021)
      A high battery temperature has been shown to be critical for lithium-ion batteries in terms of performance, degradation, and safety. Therefore, a precise knowledge of heat sources and sinks in the battery is essential. We ...