Browsing NTNU Open by Author "Marskar, Robert"
Now showing items 1-15 of 15
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Evolution of positive streamers in air over non-planar dielectrics: experiments and simulations
Meyer, Hans Kristian Hygen; Marskar, Robert; Mauseth, Frank (Peer reviewed; Journal article, 2022)We study positive streamers in air propagating along polycarbonate dielectric plates with and without small-scale surface profiles. The streamer development was documented using light-sensitive high-speed cameras and a ... -
Few- and Single-Cycle Coherent Pulse Propagation in Multi-Level Media
Marskar, Robert (Doktoravhandlinger ved NTNU, 1503-8181; 2014:154, Doctoral thesis, 2014)Recent experimental realizations of single-cycle pulses in the terahertz, infrared, and optical regions provide promising light sources for applications in telecommunication, medical imaging, spectroscopy, and coherent ... -
Lightning Impulse Testing in Short Air-Gaps and Memory Effect of Previous Discharges
Subhana, Arik; Støa-Aanensen, Nina Sasaki; Gammelsæter, Marte; Marskar, Robert; Mauseth, Frank (Peer reviewed; Journal article, 2024)This paper reports on an observed phenomenon of increasing breakdown voltage while performing standard up and down lightning impulse (LI) testing in short air-gaps with weakly non-uniform field in an enclosed volume. The ... -
Multilevel Maxwell-Bloch simulations in inhomogeneously broadened media
Marskar, Robert; Österberg, Ulf Lennart (Journal article; Peer reviewed, 2011)A compact numerical method for simulating ultrafast pulse interaction with inhomogeneously broadened multi-level media is reported. We use a low-dispersion pseudospectral scheme with fourth order time stepping for Maxwell’s ... -
New Environmentally-friendly Insulation Gases - Positive and Negative Streamer Propagation Along Micro-Profiled Dielectric Surfaces
Klævold, Kari Sværen (Master thesis, 2024)Gassen svovelheksafluorid (SF6) er et foretrukket isolasjonsmedium i innkapslede høyspenningssystemer på grunn av sine utmerkede dielektriske, termiske og elektronegative egenskaper. Im- idlertid har gassen et betydelig ... -
Nonlinear Vibration-Rotation Modes Of Inviscid Droplets
Marskar, Robert (Master thesis, 2009) -
Positive and Negative Streamer Propagation Along Profiled Dielectric Surfaces
Bilsbak, Henriette (Master thesis, 2021)Behovet for kostnadseffektive og solide SF6-frie isolasjonssystemer for MV koblingsanlegg øker forskningsinteressen for å forstå mekanismene bak streamerutbredelse langs dielektriske plater. Avhandlingen undersøker hvordan ... -
Simulations and Measurements of Streamer discharges near Dielectrics
Midttun, Sigurd Gard (Master thesis, 2017)A novel numerical fluid model for simulating streamer discharges has been tested and utilized with a two-diemnsional triple junction configuration. The triple junction was located at the upper end of a 1 cm dielectric rod, ... -
Streamer and surface charge dynamics in non-uniform air gaps with a dielectric barrier
Meyer, Hans Kristian Hygen; Marskar, Robert; Blaszczyk, Andreas; Mauseth, Frank; Pedersen, Per Atle (Journal article; Peer reviewed, 2019)Streamer behaviour near dielectric surfaces is an important characteristic of air-solid electrical insulation systems. Accurate predictions are important for dielectric design, but dynamic aspects such as surface charging ... -
Streamer inception in technical air with and without C5-fluoroketone for a rod-plane gap
Skirbekk, Fanny; Marskar, Robert; Meyer, Hans Kristian Hygen; Mauseth, Frank (Chapter, 2024)In this study, the inception probability of negative streamers in technical air with 7.5 %vol C5-fluoroketone (C5-FK+air) at 1.0 bar absolute pressure is studied. Similar tests were done for both polarities in technical ... -
Streamer inception probability in air at atmospheric pressure - An experimental and theoretical analysis
Skirbekk, Fanny; Meyer, Hans Kristian Hygen; Mauseth, Frank; Marskar, Robert (Journal article; Peer reviewed, 2024)We consider a self-consistent and probabilistic formulation of the classical Raether-Meek streamer inception model, and compare it with dedicated experiments. Our approach is based on the statistical evaluation of a first ... -
Streamer propagation along a profiled dielectric surface
Meyer, Hans Kristian Hygen; Marskar, Robert; Gjemdal, Henrik; Mauseth, Frank (Peer reviewed; Journal article, 2020)We investigate the propagation of positive streamers along a profiled dielectric surface in air at atmospheric pressure. Results from experiments and two-dimensional planar low-temperature plasma fluid simulations are ... -
Streamer Propagation along Dielectric Surfaces
Gjemdal, Henrik (Master thesis, 2019)Avhandlingen undersøker hvordan streamerutbredelse langs en dielektrisk overflate påvirkes av profilen på overflaten. Et eksperimentelt oppsett er utformet for å etterligne en 2D modell som også simuleres. Simuleringsprogramvaren ... -
Streamer Propagation along Profiled Insulator Surfaces under Positive Impulse Voltages
Meyer, Hans Kristian Hygen; Marskar, Robert; Bilsbak, Henriette Graverholt; Mauseth, Frank; Schueller, Michael (Peer reviewed; Journal article, 2022)Controlling discharge growth on insulator surfaces is important in high voltage gaseous insulation systems. In this study, the effect of small-scale surface profiles on streamer discharge propagation is examined experimentally. ... -
Surface Flashover over a Micro-Profiled Cylinder in Air
Meyer, Hans Kristian Hygen; Marskar, Robert; Osberg, Helene; Mauseth, Frank (Peer reviewed; Journal article, 2023)Increasing the lightning impulse (LI) flashover voltage of insulators can require significant changes to the geometry and material properties of the insulator or electrodes. In some cases, such changes can be difficult to ...