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norskFakultet for ingeniørvitenskap og teknologi: Nye registreringer
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Sensitivity Analysis and Case Studies for CO2 Transportation Energy Consumption
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020)The transportation of CO2 is important to all Carbon Capture and Storage (CCS) projects. Both the infrastructure costs – compressors, pipelines, tanker ships, etc. – and the energy consumed in the compression or liquefaction of CO2 are significant. Understanding how the size, capacity and energy consumption of transportation alternatives varies between projects is therefore important. Modelling ... -
Optimization study of heat pumps using refrigerant blends – Ejector versus expansion valve systems
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-11-19)This article investigates tap water heating systems to highlight an ongoing debate. Some report that CO2-based transcritical heat pumps with an ejector have the best coefficient of performance (COP), while others report that blend-based refrigerant systems (without an ejector) are better. In the literature, however, these systems are only compared with conventional heat pump designs, and not against ... -
Mathematical modelling of bioenergy systems for stability analysis and parametric sensitivity
(Doctoral thesis; Doktorgradsavhandling, 2021-03-19)<p>This thesis presents a research study on bioreactor design and biochemical processes for conversion of biomass into bioenergy and develops mathematical models that can be used for designing better reactors and control systems. Good design of the bioreactors and understanding of the biochemical process is essential to control the process for maximizing the yield. Improving the performance efficiency ... -
Conjugate Heat Transfer Model Based on SIMPLE and Coupled Energy and Heat Equations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-01-28)In this study, a numerical weak coupling strategy for the modeling of a conjugate heat transfer phenomenon is considered. Where the incompressible Navier-Stokes equations are solved using the Semi-Implicit Method for Pressure Linked Equations (SIMPLE) as a first step, and then the heat conduction equation for solid is solved in a second step considering the convective velocity field resulting from ... -
Poly[2,2′-(4,4′-bipyridine)-5,5′-bibenzimidazole] functionalization of carbon black for improving the oxidation stability and oxygen reduction reaction of fuel cells
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-20)The rapid oxidation of carbon black (CB) is a major drawback for its use as a catalyst support in polymer electrolyte fuel cells. Here, we synthesize poly[2,20 -(4,40 -bipyridine)-5,50 -bibenzimidazole] (BiPyPBI) as a conducting polymer and use it to functionalize the surface of CB and homogenously anchor platinum metal nanoparticles (Pt-NPs) on a CB surface. The as-prepared materials were ... -
Study of ice accretion on wind turbine blade profiles using thermal infrared imaging
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-08)Atmospheric icing has been recognized as hindrance in proper utilization of good wind resources in cold regions. There is a growing need to better understand the ice accretion physics along wind turbine blades to improve its performance and for optimal design of anti/de-icing system. This article describes a study of ice accretion along wind turbine blade profiles using thermal infrared imaging. Surface ... -
Electric Ships in Norway - Experiences and Future trends.
(Conference object; Konferansebidrag, 2020) -
Modelling Multi-layer Hydronic Radiators
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-30)This report simulates Purmo type C22 and C33 radiators with both standard calculation and heat transfer method with help of Matlab/Simulink. Simulation results are presented to describe the radiators’ thermal performances with different simulation strategies. The deviations between two different calculation methods are identified and the heat transfer radiator model can be improved with more ... -
Adaptive Backstepping Control for a Fully-Actuated Rigid-Body in a Dual-Quaternion Framework
(Chapter; Bokkapittel, 2020-03-12)We address the trajectory tracking problem for a fully actuated rigid-body with unknown mass and inertia parameters and unknown disturbance forces, using an adaptive backstepping controller based on dual-quaternions. We show that the proposed controller, in closed loop with a nonlinear model of the system, renders the equilibrium points uniformly asymptotically stable. The proposed controller ... -
Reactive-Based Position Control of an Underactuated Quadrotor
(Chapter; Bokkapittel, 2020-07-20)This paper addresses the problem of position control or waypoint tracking for an underactuated quadrotor. The proposed control law is what is known as reaction based in the way that the attitude system reacts to errors in the translational motion. This methodology requires no generation of desired attitude or angular velocity and the resulting control law is model-independent in that it does ... -
First-year engineering students’ mathematics task performance and its relation to their motivational values and views about mathematics
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-26)This study investigates Finnish, Norwegian, and Swedish first-year engineering students’ task performance in mathematics and examines how it relates to their motivational values and beliefs about the nature of mathematics. In a set of seven mathematical tasks, female students outperformed male students, for example, in the simplification of symbolic expressions. Our findings also show that ... -
Asymptotics of fundamental solutions for time fractional equations with convolution kernels
(Journal article; Peer reviewed, 2020-09-11)The paper deals with the large time asymptotic of the fundamental solution for a time fractional evolution equation with a convolution type operator. In this equation we use a Caputo time derivative of order α ∈ (0, 1), and assume that the convolution kernel of the spatial operator is symmetric, integrable and shows a super-exponential decay at infinity. Under these assumptions we describe the ... -
Influence of seasonal mesoscale and microscale meteorological conditions in Svalbard on results of monitoring of long-range transported pollution [poster]
(Conference object; Konferansebidrag, 2018)The Zeppelin Observatory is an atmospheric monitoring station located on the northwest coast of Spitzbergen island, in the Svalbard archipelago. The station provides background air composition, meteorological and climatological data for numerous research projects. The observatory is located on a mountain ridge in a region with complex topography that affects local atmospheric circulation ... -
Fluid-Structure Interaction (FSI) of Aquaculture Net Cages [poster}
(Conference object; Konferansebidrag, 2018)The number of good sites in less exposed locations for aquaculture farming is limited. Trends are now that the fish cages are increasing in both width and depth as well as more weather-exposed locations, are taken into use. As the net cages continue to increase in size, so does the material costs. The design of the sea cages should be modified for safe and reliable use in remote offshore locations. ... -
Green Building in the Arctic Region: State-of-the-Art and Future Research Opportunities
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-10)The concept of Green Building refers to environmentally friendly constructions with the target of minimizing the impact on the natural environment through sustainable and efficient use of resources over their life cycle. Since modern buildings are large contributors to global energy consumption and greenhouse gas emissions, policies and international strategies intended to reduce the carbon footprint ... -
Multiphysics Analysis of Contact Pressure Profile of Airless tires as compared to Conventional Tires
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-15)The harsh climate of the Arctic has always posed significant challenges to car drivers. The severe loss in traction due to snow and icing on the roads has led to an increased risk of collisions. The purpose of this work is to replace the conventional air-filled tire with a non-pneumatic tire to improve the grip in the Arctic conditions. The grip obtained for tires is determined by the weight of the ... -
CFD modelling of pollutant transport
(Conference object; Konferansebidrag, 2018)With the increase of the human activities in the Arctic, including land and sea, is resulting in higher release of pollutants to the environment. These pollutants can be categorised as gases released in the air such as carbon dioxide, sulphur dioxide, NOx, etc., and waste released in seas such as chemical toxins, microplastic, etc. This work presents a computational fluid dynamics (CFD) study ... -
IR THERMOGRAPHY in Multiphysics Applications
(Conference object; Konferansebidrag, 2018)It is seen that Infrared (IR) thermography is becoming one of the very popular and effective methods in the industry as well as research and development sectors. IR thermography being a remote non-contact/non-destructive means of testing is perfectly suitable for tests in extreme environments. In addition, it is fast, reliable and detailed. Due to the advantages offered by IR thermography, it is ... -
Is Thorium a Viable Nuclear Fuel? [poster]
(Conference object; Konferansebidrag, 2018)Thorium was discovered in 1829 by the Norwegian mineralogist Morten Thrane Esmark and identified by the Swedish chemist Jöns Jacob Berzelius, who named it after Thor, the Norse god of thunder. Thorium is more abundant in nature than Uranium. It is fertile rather than fissile, and can only be used as a fuel in conjunction with a fissile material such as recycled plutonium. Thorium fuels can breed ... -
Infrared Thermography (IRT) of Conjugate Heat Transfer (CHT) Problem and Comparison with Multiphysics Model
(Conference object; Konferansebidrag, 2018)This work presents a problem undergoing conjugate heat transfer (CHT). Conjugate heat transfer problems are common is domestic heating/cooling, industrial heat exchangers, cooling of electronics (e.g. PC fans). It is to be noted that in conjugate heat transfer problems, the convection part of the heat transfer is dominated. In the given study, a hypothetical case is built where a heat source (a ...
