Browsing NTNU Open by Author "Stieng, Lars Einar"
Now showing items 1-8 of 8
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Load case reducation for offshore wind turbine support structure fatigue assessment by importance sampling with two-stage filtering
Stieng, Lars Einar; Muskulus, Michael (Journal article; Peer reviewed, 2019)A complete fatigue assessment for operational conditions for offshore wind turbines involves simulating thousands of environmental states. For applications such as optimization, where this assessment needs to be repeated ... -
Modeling Uncertainty in Extrapolated Extreme Loads for Offshore Wind Turbine Support Structures
Stieng, Lars Einar; Muskulus, Michael (Chapter, 2018)In this paper we show how a new idea for how to calculate the derivatives of extrapolated 50-year return values, used in extreme load safety criteria, can be used to estimate the uncertainty in these return values resulting ... -
On gradient-based optimization of jacket structures for offshore wind turbines
Oest, Jacob; Sandal, Kasper; Schafhirt, Sebastian; Stieng, Lars Einar; Muskulus, Michael (Journal article; Peer reviewed, 2018)During the bidding or very early design phases of jacket structures for offshore wind turbines, there may be very limited information available on meteorological conditions, soil conditions, turbine specifications, etc. ... -
Reducing the number of load cases for fatigue damage assessment of offshore wind turbine support structures using a simple severity-based sampling method
Stieng, Lars Einar; Muskulus, Michael (Journal article; Peer reviewed, 2018)The large amount of computational effort required for a full fatigue assessment of offshore wind turbine support structures under operational conditions can make these analyses prohibitive, especially for applications like ... -
Relative assessment of fatigue loads for offshore wind turbine support structures
Stieng, Lars Einar; Hetland, Ruth; Schafhirt, Sebastian; Muskulus, Michael (Journal article; Peer reviewed, 2015)Time domain analyses of Offshore Wind Turbines involve a lot of computational effort. In this paper, we present a method for reducing this effort by using results from analyses with shorter simulation lengths to predict ... -
Sampling Methods For Simplified Offshore Wind Turbine Support Structures Load Case Assessment
Stieng, Lars Einar; Muskulus, Michael (Chapter, 2018)In this work, we present four different methodologies for reducing the computational effort of fatigue assessment for offshore wind turbine support structures. To test these methods, we use them to predict the total fatigue ... -
Structural Reliability Analysis and Robust Design of Offshore Wind Turbine Support Structures
Llado, Marc Garcia (Master thesis, 2015)The purpose of this master thesis is to develop and evaluate a novel approach for performing structural reliability analysis and robust design of offshore wind turbine support structures. Offshore wind turbines are structures ... -
The Diffuse Synchrotron Radio Background from Normal Spiral Galaxies in the Context of the ARCADE Excess
Stieng, Lars Einar (Master thesis, 2013)In this thesis, the possibility that synchrotron radiation from cosmic ray electrons in normal spiral galaxies can account for the ARCADE excess is investigated. The ARCADE excess is an excess flux measured in the sky ...