Blar i NTNU Open på forfatter "Hansen, Alex"
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Role of Pore-Size Distribution on Effective Rheology of Two-Phase Flow in Porous Media
Roy, Subhadeep; Sinha, Santanu; Hansen, Alex (Peer reviewed; Journal article, 2021)Immiscible two-phase flow of Newtonian fluids in porous media exhibits a power law relationship between flow rate and pressure drop when the pressure drop is such that the viscous forces compete with the capillary forces. ... -
Semiconductor core fibers for terahertz applications
Sørgård, Trygve Reinertsen (Doctoral theses at NTNU;2021:156, Doctoral thesis, 2021)There are currently no usable waveguides or fibers for the THz frequency range, limiting opportunities for THz applications. This thesis describes a variety of considerations related to the characterization of silicon-core ... -
Simulation of Two-Phase Flow in Porous Media using a Network Model.
Harris, Eivind Eskerud (Master thesis, 2016)A network simulator has been used to study two-phase flow in porous media. The medium has been modeled as a bundle of tubes and the capillary forces inside these tubes have been investigated. This has been done by applying ... -
Soft-Clamp Fiber Bundle Model and Interfacial Crack Propagation: Comparison Using a Non-linear Imposed Displacement
Stormo, Arne; Lengliné, Olivier; Schmittbuhl, Jean; Hansen, Alex (Peer reviewed; Journal article, 2016)We compare experimental observations of a slow interfacial crack propagation along an heterogeneous interface to numerical simulations using a soft-clamped fiber bundle model. The model consists of a planar set of brittle ... -
Solving the Inverse Problem of Electrical Resistivity Tomography by Simulated Annealing
Børseth, Frode Thorsen (Master thesis, 2018)A detailed account is given of an educational visit with the company Ruden AS, which served as an introduction to the field of Electrical Resistivity Tomagraphy (ERT). The formal Calder\'on problem is presented afterwards, ... -
Stable and efficient time integration of a dynamic pore network model for two-phase flow in porous media
Gjennestad, Magnus Aashammer; Vassvik, Morten; Kjelstrup, Signe; Hansen, Alex (Journal article; Peer reviewed, 2018)We study three different time integration methods for a dynamic pore network model for immiscible two-phase flow in porous media. Considered are two explicit methods, the forward Euler and midpoint methods, and a new ... -
A statistical mechanics framework for immiscible and incompressible two-phase flow in porous media
Hansen, Alex; Flekkøy, Eirik Grude; Sinha, Santanu; Slotte, Per Arne (Peer reviewed; Journal article, 2022)We construct a statistical mechanics for immiscible and incompressible two-phase flow in porous media under local steady-state conditions based on the Jaynes maximum entropy principle. A cluster entropy is assigned to our ... -
Statistical Properties of a Single-Phase Bingham Fluid in a Porous Media
Hennig, Andreas Andersen (Master thesis, 2023)Del I (Prosjektoppgave): Effekten av en Terskelstressreologi på Strømninger i Porøse Medier Tofasestrømmer i porøse medier er komplekse fenomener som foregår over alt, fra et delikat pennestrøk til utvinning av grunnvann ... -
Statistics of Electric Power Blackouts: Data Analysis and Data Modeling
Gebremedhin-Abraha, Friew (Master thesis, 2013)We tried to see the scaled window variance and rescaled window variance statistics of the North American, Norwegian and Ethiopian blackouts. Beside we also see the square lattice modelling of blackout distribution. The ... -
Steady-State Two-Phase Flow of Compressible and Incompressible Fluids in a Capillary Tube of Varying Radius
Cheon, Hyejeong; Fyhn, Hursanay; Hansen, Alex; Wilhelmsen, Øivind; Sinha, Santanu (Peer reviewed; Journal article, 2023)We study immiscible two-phase flow of a compressible and an incompressible fluid inside a capillary tube of varying radius under steady-state conditions. The incompressible fluid is Newtonian and the compressible fluid is ... -
Stretching, breaking, and dissolution of polymeric nanofibres by computer experiments
Bering, Eivind (Doctoral theses at NTNU;2021:176, Doctoral thesis, 2021)Bundles of polymeric materials are ubiquitous and play essential roles in biological systems, and often display remarkable mechanical properties. With the never-ending experimental advances in control and manipulation of ... -
Studies of the Configurational Probability of Immiscible Two-Phase Flow in Porous Media
Brevig, Marthe (Master thesis, 2021)I denne oppgaven er en studie av konfigurasjonssannsynligheten for ublandbar tofasestrømning i porøse medier blitt utført. For å simulere strømningen, er en dynamisk nettverksmodell blitt tatt i bruk. Markov Chain Monte ... -
The Breaking Process of an Idealized Polymeric Bundle under Applied Tensile Stress
Linga, Gaute (Master thesis, 2014)We introduce a particle-based model of an idealized polymeric bundle, whose properties are investigated by means of molecular dynamics simulations. We analyse in particular the effect of applying a tensile stress, stretching ... -
The impact of wettability alterations on oil release and transport mechanisms in a 2D porous medium
Flovik, Vegard (Master thesis, 2012)The effects of wettability alterations in a 2D network model of a porous media has been studied. By changing the wetting properties of the reservoir through a developed wettability changing algorithm, previously immobile ... -
The Lattice Boltzmann Method for Steady State Sediment Transport.
Klemsdal, Thor Olaf (Master thesis, 2016)Simulating water behaviour in coastal areas is an important tool when predicting sedimentary processes over geological time. We implement a general lattice Boltzmann model for shallow water flow, that can handle having ... -
Thermal processing of semiconductor alloy core glass fibers
Song, Seunghan (Doctoral theses at NTNU;2021:409, Doctoral thesis, 2021)Semiconductor core glass-clad fibers are of great interest as optical and optoelectronic platforms for their high transparency in infrared and the potential control of their electrical properties by doping or strain ... -
The Three Extreme Value Distributions: An Introductory Review
Hansen, Alex (Peer reviewed; Journal article, 2020)The statistical distribution of the largest value drawn from a sample of a given size has only three possible shapes: it is either a Weibull, a Fréchet or a Gumbel extreme value distributions. I describe in this short ... -
Topological impact of constrained fracture growth
Hope, Sigmund Mongstad; Davy, Philippe; Maillot, Julien; Le Goc, Romain; Hansen, Alex (Journal article; Peer reviewed, 2015-09-08)The topology of two discrete fracture network models is compared to investigate the impact of constrained fracture growth. In the Poissonian discrete fracture network model the fractures are assigned length, position and ... -
Topology of fracture networks
Andresen, Christian Andre; Hansen, Alex; Le Goc, Romain; Davy, Philippe; Hope, Sigmund Mongstad (Journal article; Peer reviewed, 2013)We propose a mapping from fracture systems consisting of intersecting fracture sheets in three dimensions to an abstract network consisting of nodes and links. This makes it possible to analyze fracture systems with the ... -
Transition from viscous fingers to foam during drainage in heterogeneous porous media
Lanza, Federico; Sinha, Santanu; Hansen, Alex; Rosso, Alberto; Talon, Laurent (Peer reviewed; Journal article, 2023)We investigate the behavior of drainage displacements in heterogeneous porous media finding a transition from viscous fingering to foam-like region. A pore network model incorporating the formation of blobs is adopted to ...