Blar i NTNU Open på forfatter "Moan, Torgeir"
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Dynamic Analysis of a Floating Wind Turbine with a Hydraulic Transmission System
Yang, Limin; Jiang, Zhiyu; Gao, Zhen; Moan, Torgeir (Chapter, 2015)A 5 MW spar-type floating wind turbine equipped with high-pressure hydraulic transmission machinery is presented in this paper. The hydraulic transmission system consists of a hydraulic pump, a nonreturn check valve, a ... -
Dynamic analysis of floating wind turbines during pitch actuator fault, grid loss, and shutdown
Bachynski, Erin Elizabeth; Etemaddar, Mahmoud; Kvittem, Marit Irene; Luan, Chenyu; Moan, Torgeir (Journal article; Peer reviewed, 2013)Coupled non-linear aero-hydro-servo-elastic simulations of three types of floating wind turbines (spar, semi- submersible, and tension leg platform) are carried out for several fault cases over a range of environmental ... -
Dynamic Analysis of the Installation of Monopiles for Offshore Wind Turbines
Li, Lin (Doctoral thesis at NTNU;2016:139, Doctoral thesis, 2016)The installation of offshore wind farms presents great challenges as the industry move farther offshore and into deeper waters, and the turbines and foundations are getting larger and heavier. Current installation methods ... -
A Dynamic Approach to Evaluating the Effect of Slamming on a Jacket Foundation Template Lowered Through the Wave Zone
Nous, Roel Johannes Maria (Master thesis, 2015)The joint venture between Boskalis and VolkerWessels is responsible for installing 70 jacket foundations for the Wikinger offshore wind farm. The critical phase in this installation procedure is lowering a jacket foundation ... -
Dynamic Behaviour Comparison of a 10-MW Drivetrain in a Bottom-Fixed Monopile and a Spar Floating Wind Turbines
Wang, Shuaishuai; Rasekhi Nejad, Amir; Moan, Torgeir (Chapter, 2020)Up to now, very little attentions have been paid to multi-megawatt off shore wind turbine drivetrains. In order to improve the reliability of the offshore wind turbine drivetrain, a better understanding of its dynamic ... -
Dynamic behaviour of anchor handling vessels during anchor deployment
Wu, Xiaopeng; Moan, Torgeir (Journal article; Peer reviewed, 2017)Anchor handling operation (AHO) is potentially hazardous, as for instance demonstrated by the Bourbon Dolphin accident in 2007. Although the accident has been studied by various parties, there has been limited focus on the ... -
Dynamic Modelling and Analysis of Three Floating Wind Turbine Concepts with Vertical Axis Rotor
Cheng, Zhengshun; Wang, Kai; Gao, Zhen; Moan, Torgeir (Proceedings of the twenty-fifth International Ocean and Polar Engineering Conference;ISOPE 2015, Chapter, 2015)Recently there is an increasing interest in the development of offshore floating vertical axis wind turbines (FVAWTs). A FVAWT mounted on a semi-submersible has been proposed by several researchers, and a FVAWT with a spar ... -
Dynamic Response Analysis of a Floating Bridge Subjected to Environmental Loads
Cheng, Zhengshun; Gao, Zhen; Moan, Torgeir (Chapter, 2018)Designing floating bridges for wide and deep fjords is very challenging. The floating bridge is subjected to wind, wave, and current loads. All these loads and corresponding load effects should be properly evaluated, e.g. ... -
Dynamic response analysis of floating wind turbines with emphasis on vertical axis rotors
Cheng, Zhengshun; Moan, Torgeir; Gao, Zhen (Chapter; Peer reviewed, 2016)Large floating wind turbines are feasible for offshore application. Due to the commercial success onshore and nearshore, floating horizontal axis wind turbines (HAWTs) are now being widely studied. However, floating vertical ... -
Dynamic Response Analysis of Three Floating Wind Turbine Concepts with a Two-Bladed Darrieus Rotor
Cheng, Zhengshun; Wang, Kai; Gao, Zhen; Moan, Torgeir (Journal article; Peer reviewed, 2015)Recently, interest in the development of floating vertical axis wind turbines (FVAWTs) has been increasing, since FVAWTs might prove to be one of the optimal configurations in deep waters. In this study, a FVAWT with a 5 ... -
Effect of Flap Type Wave Energy Converters on the Response of a Semi-Submersible Wind Turbine in Operational Conditions
Michailidis, Konstantinos; Luan, Chenyu; Gao, Zhen; Moan, Torgeir (Chapter; Peer reviewed, 2014)In the present paper the effect of flap type wave energy converters on the response of a floating semi-submersible wind turbine is investigated and reported. Two different layouts with regard to the number of rotating flaps ... -
Effect of hydrodynamic load modelling on the response of floating wind turbines and its mooring system in small water depths
Xu, Kun; Gao, Zhen; Moan, Torgeir (Journal article; Peer reviewed, 2018)A large number of offshore wind turbines have been installed recently, mostly in water depth up to 30 m based on monopile foundations. It is expected that floating wind turbine becomes more competitive than bottom fixed ... -
Effect of ship speed on ship’s ice resistance with ship’s vertical motions included
Tan, Xiang; Riska, Kaj; Moan, Torgeir (Chapter, 2013)In this paper, the relations between ice resistance, shipspeed and ship motions are investigated with a numericalmodel simulating the icebreaking process with ship'smotions in 6 degrees of freedom (DOF). The coupledmotions ... -
Effect of ship speed on ship’s ice resistance with ship’s vertical motions included
Tan, Xiang; Riska, Kaj; Moan, Torgeir (Chapter, 2013)In this paper, the relations between ice resistance, shipspeed and ship motions are investigated with a numericalmodel simulating the icebreaking process with ship'smotions in 6 degrees of freedom (DOF). The coupledmotions ... -
Effect of the number of blades on the dynamics of floating straight-bladed vertical axis wind turbines
Cheng, Zhengshun; Madsen, Helge Aagard; Gao, Zhen; Moan, Torgeir (Journal article; Peer reviewed, 2017)Floating vertical axis wind turbines (VAWTs) are promising solutions for exploiting the wind energy resource in deep waters due to their potential cost-of-energy reduction. The number of blades is one of the main concerns ... -
Effect of wave inhomogeneity on fatigue damage of mooring lines of a side-anchored floating bridge
Dai, Jian; Leira, Bernt Johan; Moan, Torgeir; Alsos, Hagbart Skage (Peer reviewed; Journal article, 2020)Mooring systems are important structural components of very long floating bridges. They effectively limit the transverse motions of the bridge under environmental loads. They also add viscous hydrodynamic damping to the ... -
Effect of wave nonlinearity on fatigue damage and extreme responses of a semi-submersible floating wind turbine
Xu, Kun; Min, Zhang; Shao, Yanlin; Gao, Zhen; Moan, Torgeir (Journal article; Peer reviewed, 2019)Floating wind turbine has been the highlight in offshore wind industry lately. There has been great effort on developing highly sophisticated numerical model to better understand its hydrodynamic behaviour. A engineering-practical ... -
Effects of bedplate flexibility on drivetrain dynamics: Case study of a 10 MW spar type floating wind turbine
Wang, Shuaishuai; Rasekhi Nejad, Amir; Bachynski, Erin Elizabeth; Moan, Torgeir (Peer reviewed; Journal article, 2020)This paper deals with the effect of bedplate flexibility on drivetrain dynamics of a 10 MW spar type floating wind turbine. The 10 MW drivetrain bedplate is designed based on extreme design loads and ultimate limit state ... -
Effects of floating sun gear in a wind turbine’s planetary gearbox with geometrical imperfections
Rasekhi Nejad, Amir; Xing, Yihan; Guo, Yi; Keller, Jonathan; Gao, Zhen; Moan, Torgeir (Journal article; Peer reviewed, 2015)This paper addresses the effect of gear geometrical errors in wind turbine planetary gearboxes with a floating sun gear. Numerical simulations and experiments are employed throughout the study. A National Renewable Energy ... -
Efficient Determination of the Long-term Extreme Responses by the Modified Environmental Contour Method for a Combined Wind Turbine and Wave Energy Converter System
Li, Qinyuan; Ren, Nianxin; Gao, Zhen; Moan, Torgeir (Journal article; Peer reviewed, 2018)This paper deals with the performance of the modified environmental contour method (MECM) for determining long-term extreme load effect in a combined wind turbine and wave energy converter system. The wind turbine of the ...