English
norskArtikler, rapporter og annet (bygg, energi og materialteknologi)
Vis alle innførsler i samlingen sortert på
Nye registreringer
-
An experimental study of effect of printed thickness on the mechanical properties of LPBF produced AlSi10Mg
(Chapter; Bokkapittel, 2024-04-24)Additive manufacturing process allows fabrication of parts with a broad range of sizes with high resolution. This size variation introduces new mechanical properties within the printed component, which creates a significant challenge for the qualification of additively manufactured parts. This unresolved issue hinders the implementation of additive manufacturing in high performance engineering ... -
Investigation into Using CFD for Estimation of Ship Specific Parameters for the SPICE Model for Prediction of Sea Spray Icing: Part 1—The Proposal
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-18)A machine learning model for prediction of icing on vessels and offshore structures, Spice, was recently developed by Deshpande 2023. Some variables required for the prediction of icing rates in most prediction models, including Spice, such as the spray flux, cannot be easily measured. Existing models estimate these using empirical formulations that have been heavily criticized. Most existing models ... -
An Investigation into Using CFD for the Estimation of Ship Specific Parameters for the SPICE Model for the Prediction of Sea Spray Icing: Part 2—The Verification of SPICE2 with a Full-Scale Test
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-18)A hybrid CFD–ML model for the prediction of sea spray icing, SPICE2, was developed in Part 1 of this study in Deshpande et al., 2024. The SPICE2 model is an extension of the ML model, SPICE, where some of the variables required for icing rate predictions: local wind speed, spray duration, spray period, and spray flux, are computed from CFD simulations. These, along with the air and water ... -
An alternative two-phase formulation and analytical solution for a Stefan problem in one-dimension accounting for volume change and sensible heat
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-09)Stefan problems, or free boundary problems, in the phase change process occur in many engineering problems. This paper develops a compact formula for a two-phase melting process in a one-dimensional semi-infinite slab with a novel approach. Unlike the classic Stefan problem, the novel approach considers volume change (or density difference) and the net-sensible-heat of the two phases. Furthermore, ... -
Full-scale tests of deicing with seawater
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-16)Sea-spray icing is one of the major hazards for small- and medium-sized vessels in polar regions. Predominant anti- and deicing measures include prevention by heeding the weather forecasts and avoiding high-risk situations, protection by enclosing exposed and high-priority areas, manual ice removal by personnel, heat tracing and surplus heat. Energy is in limited supply on vessels, and alternative ... -
Investigating the Influence of Oil Shale Ash and Basalt Composite Fibres on the Interfacial Transition Zone in Concrete
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-27)The interfacial transition zone (ITZ) is the weakest phase in concrete, characterised by higher porosity and being prone to microcrack formation. Additionally, the ITZ is created when dispersed fibre reinforcement is present. Although fibres improve flexural strength, they can negatively impact other properties. This research investigates the ITZ of fibre-reinforced concrete where macro-basalt fibres ... -
Repair Options for Corrosion-damaged Prestressed Concrete Structures
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-05)Prestressing of bridges allows construction of long spanned bridges made from thin structural members with high flexural and shear capacity. Studies have shown that some of the existing prestressed bridges are not meeting their designed service life due to corrosion of the tendons. The main reasons are poor construction practices in combination with inadequate inspection and maintenance plans. ... -
An experimental study on thermophysical properties of nano- TiO2-enhanced phase change materials for cold climate applications
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-01-30)In high-energy-demand regions, such as the Arctic, the building sector is focused on reducing the carbon footprint and mitigating environmental impact. To achieve this, phase change materials (PCMs) are being investigated for thermal energy storage due to their high latent heat of fusion. However, their limited applications arise from poor thermal conductivity. In addressing this issue, the ... -
Mechanical Properties of MiniBars™ Basalt Fiber-Reinforced Geopolymer Composites
(Journal article; Tidsskriftartikkel, 2024-01-02)Fly ash-based geopolymers represent a new material, which can be considered an alternative to ordinary Portland cement. MiniBars™ are basalt fiber composites, and they were used to reinforce the geopolymer matrix for the creation of unidirectional MiniBars™ reinforced geopolymer composites (MiniBars™ FRBCs). New materials were obtained by incorporating variable amount of MiniBars™ (0, 12.5, 25, 50, ... -
Experimental Insights into the Fermentation of Pyro-Syngas to Ethanol in a Semi-Batch and Continuous Stirred Bioreactor with Mathematical Modelling and Optimization
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-01-24)Syngas fermentation can play an important role in implementing the concept of biorefinery as it can serve as a platform to convert high-lignin biomass to biofuels. For the utilization of this process in commercial scale, the generation of an experimental database supported by a deterministic mathematical model and optimization is necessary. In this study, a locally isolated clostridial consortium, ... -
Shewanella baltica in a Microbial Fuel Cell for Sensing of Biological Oxygen Demand (BOD) of Wastewater
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-04-15)Geobacter and Shewanella are the most characterized electroactive bacteria genera. Unlike genus Geobacter that is strictly anaerobic, Shewanella can grow under both oxic and anoxic environments and is capable of metabolizing a wider substrate range. In the present study, the use of strain Shewanella baltica 20 in MFC-based biosensor for BOD monitoring is reported. The S. baltica strain 20 was isolated ... -
Experiments With Sea Spray Icing: Investigation of Icing Rates
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-11)Sea spray icing on ships and marine structures depends on a complex correlation between metocean parameters and vessel characteristics. Sea spray icing rates have mostly been investigated and given as a function of general metocean parameters. The existing models suffer from the lack of experimental data. More experimental data are required for better prediction models and understanding of the icing ... -
Experimental Investigation of Deicing with Seawater
(Chapter; Bokkapittel, 2023-06-19)Increased traffic and interest in arctic regions necessitate measures to ensure the safety and functionality of vessels. Sea-spray icing is one of the significant hazards for small- and medium-sized vessels in polar waters. Ice cover can restrict access to essential parts of a vessel and compromise its stability. Existing deicing measures, such as heat or chemical application and manual ice removal, ... -
Running out of excuses? Norwegian political and policy discourses justifying oil and gas development in the Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-02-08)In this article, we analyse how energy security are woven into political discourses among Norwegian policymakers after the Russian invasion of Ukraine and the consequences of this for intergenerational justice and environmental concerns more broadly. Preceding justifications centred on state revenue and domestic economic growth, the current discourse focuses on the European need for security of ... -
Same same, but different – or how construction informatics gets taught at universities in Norway and Sweden
(Chapter; Bokkapittel, 2023)In response to the increasing demand for construction informatics (CI) expertise, universities in the Nordic countries have developed new educational offers. This study explores how CI related education is being delivered by three different universities, two in Norway and one in Sweden. By comparing curricula and interviewing CI teachers, this paper contributes to the recent debate on the international ... -
Evaluating of melting-ice process in a vertical pipe with consideration of net sensible heat
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-19)In ice-melting process, motion of liquid–solid interface is complicated due to moving boundary, which is also called Stefan interface problem. Although the Stefan model has been widely utilized, it frequently overestimates the melting rate. In the present study, the net-sensible-heat of the phases are taken into account as an additional physical effect to the Stefan model for one-phase case and ... -
Enhanced performance of microbial fuel cells using electrochemically treated carbon felt anode
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-10)The microbial fuel cell (MFC) technology is emerging as an effective technology for wastewater treatment to remove and detect many pollutants and simultaneously generate power. The anode is an essential component for bacterial attachment and extracellular electron transfer (EET). Thus, anode performance is critical for improving an MFC system's overall performance. Materials that are electronically ... -
Assessing shielding material Performance: Benchmarking of Monte Carlo codes for oil shale and Basalt-Boron fiber concretes Hando Tohver a,* , Andrius Slavickas b , Maryna Holiuk c , Andrejs Krasn¸ i
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-12)Cement-based concretes are commonly used for managing radioactive waste due to their low cost and radiation shielding properties. However, the potential of using oil shale ash as an additive in waste packaging material has been overlooked. This study focuses on benchmarking and developing a Monte Carlo based modeling methodology using multiple transport codes (MCNP, SERPENT, SCALE, OpenMC, and ... -
Effect of pH, COD, and HRT on the Performance of Microbial Fuel Cell Using Synthetic Dairy Wastewater
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-30)Microbial fuel cells (MFC) are emerging technologies that can produce electricity while treating wastewater. A series of tests were carried out to evaluate the efficiency of this technology for treating dairy wastewater (DWW). The experiments used Shewanella baltica as an exoelectrogen in a small single MFC to treat simulated DWW. The impacts of various operational factors, specifically pH, ... -
Iron ore dust as a natural pigment in concrete with RCA for artwork application
(Chapter; Bokkapittel, 2022)A The innovative idea of utilization of iron ore dust (IODust), characterized by red hue typical for Narvik, came up during designing artwork for The Arctic University of Norway campus Narvik. The use of waste from iron ore production as a natural pigment was completed by partial replacement of natural aggregates (NA) by recycled concrete aggregates (RCA) to achieve a higher level of material ...
RSS 1.0