• Frictional Pressure Drop for Two-phase Flow of Carbon Dioxide in a Tube: Comparison between Models and Experimental Data 

      Aakenes, Frøydis; Munkejord, Svend Tollak; Drescher, Michael (Journal article; Peer reviewed, 2014)
      We compare models for two-phase frictional pressure drop with experimental data for pure CO2 taken in a tube of 10 mm inner diameter. The flow was nearly adiabatic, and the mass fluxes ranged from 1058 to 1663 kg/(m2 s), ...
    • Full Plant Scale Analysis of Natural Gas Fired Power Plants with Pre-Combustion CO2 Capture and Chemical Looping Reforming (CLR) 

      Nazir, Shareq Mohd; Bolland, Olav; Amini, Shahriar (Journal article; Peer reviewed, 2017)
      In this study, first of its kind complete plant scale integration of pre-combustion CO2 capture method with Chemical Looping Reforming (CLR) of Natural Gas (NG), Water Gas Shift (WGS) process, CO2 capture and CO2 compression ...
    • Fundamental Modeling of a Membrane Reactor with in Situ Hydrogen Separation and Combustion 

      Weydahl, Torleif; Salimath, Prashant Siddlinggayya; Gruber, Andrea (Journal article; Peer reviewed, 2013)
      In this work we consider a membrane reactor with catalytic steam methane reforming and/or water gas shift on the feed side, hydrogen separation and direct combustion of hydrogen on the permeate side, where the ultimate ...
    • Gasification of High Heating-rate Biomass-derived Chars at Elevated Temperatures 

      Li, Tian; Niu, Yanqing; Wang, Liang; Løvås, Terese (Journal article; Peer reviewed, 2017)
      In this study, gasification behavior of high heating-rate chars were investigated using an entrained flow reactor with an optical particle-sizing pyrometer. Two biomass chars produced from forest residue and torrefied ...
    • High frequency ghost cavitation - a comparison of two seismic air-gun arrays using numerical modeling 

      Khodabandeloo, Babak; Landrø, Martin (Journal article; Peer reviewed, 2017)
      Ghost cavitation is probably the mechanism behind the majority of high frequencies (above 5 kHz) generated by seismic air-gun arrays. Such high frequencies are less important in seismic reflection imaging. High frequency ...
    • High-Rise Timber Buildings as a Climate Change Mitigation Measure - A Comparative LCA of Structural System Alternatives 

      Skullestad, Julie Lyslo; Bohne, Rolf André; Lohne, Jardar (Journal article; Peer reviewed, 2016)
      This paper reports on a study examining the potential of reducing greenhouse gas (GHG) emissions from the building sector by substituting multi-storey steel and concrete building structures with timber structures. Life ...
    • Identifying operational requirements for flexible CCS plant in future energy systems 

      Mocholí Montañés, Rubén; Korpås, Magnus; Nord, Lars O.; Jaehnert, Stefan (Journal article; Peer reviewed, 2016)
      This paper aims at a discussion of operational requirements for thermal power plants with carbon capture and storage in terms of their interaction with the power system, in regions with high penetration of variable renewable ...
    • Impact of Torrefaction on Woody Biomass Properties 

      Wang, Liang; Barta-Rajnai, Eszter; Skreiberg, Øyvind; Khalil, Roger Antoine; Czégény, Zsuzsanna; Jakab, Emma; Barta, Zsolt; Grønli, Morten (Journal article; Peer reviewed, 2017)
      In this work, Norway spruce stem wood, stump and bark were torrefied in a tubular reactor. The effects of feedstock type and torrefaction process parameters such as torrefaction temperature and residence time on the ...
    • Impact of urban density and building height on energy use in cities 

      Resch, Eirik; Bohne, Rolf André; Kvamsdal, Trond; Lohne, Jardar (Journal article; Peer reviewed, 2016)
      Compact cities have been attributed to lower per capita energy use. However, the complexity of relationships between the elements that constitute energy consumption in the urban system is poorly understood. Little or no ...
    • Influence of Soil Parameters on the Fatigue Lifetime of Offshore Wind Turbines with Monopile Support Structure 

      Schafhirt, Sebastian; Page, Ana M.; Eiksund, Gudmund Reidar; Muskulus, Michael (Journal article; Peer reviewed, 2016)
      Designing support structures for offshore wind turbines is a complex task as these are highly dynamic systems subjected to long-term cyclic loads with variable amplitude. Long-term cyclic loading may cause stiffening or ...
    • Innovation in a heterogeneous CCS research centre, managerial and organizational challenges 

      Aasen, Tone Merethe; Mølnvik, Mona J.; Aarlien, Rune; Bredesen, Rune; Munkejord, Svend Tollak; Brunsvold, Amy; Gundersen, Truls (Journal article; Peer reviewed, 2012)
      Recently, the Norwegian authorities have established a number of Centres for Environment-friendly Energy Research (CEER), intended to develop new knowledge, foster breakthrough technology and promote innovation in order ...
    • Integrated Techno-economic and Environmental Assessment of an Amine-based Capture 

      Roussanaly, Simon; Brunsvold, Amy; Hognes, Erik Skontorp; Jakobsen, Jana Poplsteinova; Zhang, Xiangping (Journal article; Peer reviewed, 2013)
      A systematic methodology for integrated techno-economic and environmental assessment of CCS value chains is presented and applied to assess the impact of the CO2 concentration on an amine-based post-combustion CO2 capture ...
    • Integration of BREEAM-NOR in construction projects: Utilizing the Last Planner System 

      Nesteby, Åse Ingrid; Aarrestad, Marie Elise; Lohne, Jardar; Bohne, Rolf André (Journal article; Peer reviewed, 2016)
      According to the general literature, maximizing the potential of BREEAM-NOR could significantly contribute to create a greener and more sustainable construction industry. Lean Construction techniques promise to eliminate ...
    • Isogeometric methods for CFD and FSI-simulation of flow around turbine blades 

      van Opstal, Timo Matteo; Fonn, Eivind; Holdahl, Runar; Kvamsdal, Trond; Kvarving, Arne Morten; Mathisen, Kjell Magne; Nordanger, Knut; Okstad, Knut Morten; Rasheed, Adil; Tabib, Mandar (Journal article; Peer reviewed, 2015)
      Coupled fluid-structure interaction simulations of wind turbines have traditionally been considered computationally too expensive to carry out. However, more powerful computers and better solution techniques based on ...
    • Key performance indicators for wind farm operation and maintenance 

      Gonzalez, Elena; Nanos, Emmanouil; Seyr, Helene; Valldecabres, Laura; Yürüsen, Nurseda; Smolka, Ursula; Muskulus, Michael; Melero, Julio (Journal article; Peer reviewed, 2017)
      Key performance indicators (KPI) are tools for measuring the progress of a business towards its goals. Although wind energy is now a mature technology, there is a lack of well-defined best practices to asses the performance ...
    • Laboratory investigations of moisture conditions in wood frame walls with wood fiber insulation 

      Geving, Stig; Lunde, Erik; Holme, Jonas (Peer reviewed; Journal article, 2015)
      The purpose of this study was to investigate the moisture conditions in wood frame walls with wood fiber thermal insulation in a Nordic climate. Laboratory measurements were conducted on 15 different wall configurations. ...
    • Lidars for Wind Tunnels - an IRPWind Joint Experiment Project 

      Sjöholm, Mikael; Vignaroli, Andrea; Angelou, Nikolas; Nielsen, Morten Busk; Mann, Jakob; Mikkelsen, Torben; Bolstad, Hans Christian; Merz, Karl Otto; Sætran, Lars Roar; Mühle, Franz Volker; Tiihonen, Mikko; Lethomäki, Ville (Journal article; Peer reviewed, 2017)
      Measurement campaigns with continuous-wave Doppler Lidars (Light detection and ranging) developed at DTU Wind Energy in Denmark were performed in two very different wind tunnels. Firstly, a measurement campaign in a small ...
    • Lifetime extension for large offshore wind farms: Is it enough to reassess fatigue for selected design positions? 

      Bouty, Corantin; Schafhirt, Sebastian; Ziegler, Lisa Sabine; Muskulus, Michael (Journal article; Peer reviewed, 2017)
      Fatigue reassessment within the decision process of lifetime extension might be uneconomical when individually performed for each turbine of a large offshore wind farm. This paper analyses the possibilities to extrapolate ...
    • Long-term Analysis of Gear Loads in Fixed Offshore Wind Turbines Considering Ultimate Operational Loadings 

      Rasekhi Nejad, Amir; Gao, Zhen; Moan, Torgeir (Journal article; Peer reviewed, 2013)
      The long-term extreme value analysis of gear transmitted load due to the main shaft torque is presented. Two methods, the multibody simulations (MBS) and a simplified method, are demonstrated for the gear transmitted load ...
    • Maintenance Strategies for Large Offshore Wind Farms 

      Scheu, Matti Niclas; Matha, Denis; Hofmann, Matthias; Muskulus, Michael (Journal article; Peer reviewed, 2012)
      Up to one third of the total cost of energy from offshore wind generation is contributed by operation and maintenance (O&M). Compared to its onshore counterpart, this fraction is significantly higher. Costs are not only ...