Browsing NTNU Open by Author "Verma, Amrit Shankar"
Now showing items 1-20 of 20
-
A comprehensive numerical investigation of the impact behaviour of an offshore wind turbine blade due to impact loads during installation
Verma, Amrit Shankar; Vedvik, Nils Petter; Gao, Zhen (Journal article, 2019)For installing offshore wind turbines into deep waters, use of floating crane vessels is essential. One of the major challenges is their sensitivity to wave-induced vessel and crane tip motions, which can cause the impact ... -
A Global-local Damage Assessment Methodology for Impact Damage on Offshore Wind Turbine Blades during Lifting Operations
Verma, Amrit Shankar; Haselbach, Philipp Ulrich; Vedvik, Nils Petter; Gao, Zhen (Chapter, 2018)Lifting the latest generation offshore wind turbines using floating crane vessels is extremely challenging. This comes with an elevated risk of blades impacting the tower or surrounding structures due to excessive crane ... -
A Summary of the Recent Work at NTNU on Marine Operations Related to Installation of Offshore Wind Turbines
Gao, Zhen; Verma, Amrit Shankar; Zhao, Yuna; Jiang, Zhiyu; Ren, Zhengru (Chapter, 2018)In this paper, a summary of the recent work at NTNU on the installation of offshore wind turbines using jack-up and floating vessels will be reported. The wind turbine components considered here are the monopile foundations ... -
Active heave compensation of floating wind turbine installation using a catamaran construction vessel
Ren, Zhengru; Skjetne, Roger; Verma, Amrit Shankar; Jiang, Zhiyu; Gao, Zhen; Halse, Karl Henning (Peer reviewed; Journal article, 2021)The application of floating wind turbines is limited by the high cost that increases with the water depth. Offshore installation and maintenance continue to consume a high percentage of the project budget. To improve the ... -
Comparison of numerical modelling techniques for impact investigation on a wind turbine blade
Verma, Amrit Shankar; Vedvik, Nils Petter; Haselbach, Philipp Ulrich; Gao, Zhen; Jiang, Zhiyu (Journal article; Peer reviewed, 2019)Wind turbine blades are exposed to numerous impact risks throughout their lifetimes. The impact risks range from bird collisions during operation to impacts with surrounding structures at the time of transportation and ... -
Damage identification of a jacket support structure for offshore wind turbines
Jiang, Zhiyu; Bjørnholm, Marius; Guo, Jiamin; Dong, Wenbin; Ren, Zhengru; Verma, Amrit Shankar (Chapter, 2020)Offshore jacket structures are regarded as a suitable type of support structure for offshore wind turbines in immediate water depths. Because of the welded tubular members used and environmental conditions, offshore jackets ... -
Effects of a Passive Tuned Mass Damper on Blade Root Impacts During the Offshore Mating Process
Verma, Amrit Shankar; Jiang, Zhiyu; Gao, Zhen; Vedvik, Nils Petter (Peer reviewed; Journal article, 2020)Single-blade installation is a conventional method for installing blades on monopile-type offshore wind turbines. A jack-up crane vessel is commonly used, and individual blades are lifted to the tower top height and mated ... -
Effects of onshore and offshore environmental parameters on the leading edge erosion of wind turbine blades: A comparative study
Verma, Amrit Shankar; Jiang, Zhiyu; Ren, Zhengru; Hu, Weifei; Teuwen, Julie J.E. (Peer reviewed; Journal article, 2021)The presence of rain-induced leading edge erosion of wind turbine blades necessitates the development of erosion models. One of the essential parameters for erosion modelling is the relative impact velocity between rain ... -
Effects of Wind-Wave Misalignment on a Wind Turbine Blade Mating Process: Impact Velocities, Blade Root Damages and Structural Safety Assessment
Verma, Amrit Shankar; Jiang, Zhiyu; Ren, Zhengru; Gao, Zhen; Vedvik, Nils Petter (Peer reviewed; Journal article, 2020)Most wind turbine blades are assembled piece-by-piece onto the hub of a monopile-type offshore wind turbine using jack-up crane vessels. Despite the stable foundation of the lifting cranes, the mating process exhibits ... -
Explicit Structural Response-Based Methodology for Assessment of Operational Limits for Single Blade Installation for Offshore Wind Turbines
Verma, Amrit Shankar; Zhao, Yuna; Gao, Zhen; Vedvik, Nils Petter (LNCE;volume 23, Chapter; Conference object, 2019)The growing requirements of large-sized offshore wind turbines require heavier components to be lifted to large heights using installation vessels. This imposes a substantial risk of impact to the lifted components especially ... -
Impact assessment of a wind turbine blade root during an offshore mating process
Verma, Amrit Shankar; Jiang, Zhiyu; Vedvik, Nils Petter; Gao, Zhen; Ren, Zhengru (Journal article; Peer reviewed, 2019)Single-blade installation is a popular method for installing blades on bottom-fixed offshore wind turbines. A jack-up crane vessel is often employed, and individual blades with their roots equipped with mechanical joints ... -
Integrated GNSS/IMU Hub Motion Estimator for Offshore Wind Turbine Blade Installation
Ren, Zhengru; Skjetne, Roger; Jiang, Zhiyu; Gao, Zhen; Verma, Amrit Shankar (Journal article; Peer reviewed, 2019)Offshore wind turbines (OWTs) have become increasingly popular for their ability to harvest clean offshore wind energy. Bottom-fixed foundations are the most used foundation type. Because of its large diameter, the foundation ... -
Minimum leading edge protection application length to combat rain-induced erosion of wind turbine blades
Verma, Amrit Shankar; Di Noi, Sandro; Ren, Zhengru; Jiang, Zhiyu; Teuwen, Julie J. E. (Peer reviewed; Journal article, 2021)Leading edge erosion (LEE) repairs of wind turbine blades (WTBs) involve infield application of leading edge protection (LEP) solutions. The industry is currently aiming to use factory based LEP coatings that can applied ... -
Model-free anti-swing control of complex-shaped payload with offshore floating cranes and a large number of lift wires
Ren, Zhengru; Verma, Amrit Shankar; Ataei, Behfar; Halse, Karl Henning; Hildre, Hans Petter (Peer reviewed; Journal article, 2021)Being one of the most commonly used offshore operations, offshore lifting operations become increasingly challenging due to the gradually growing size and weight of payloads. The research on automatic control in lifting ... -
Modelling, Analysis and Response-Based Operability Assessment of Offshore Wind Turbine Blade Installation with Emphasis on Impact Damages
Verma, Amrit Shankar (Doctoral theses at NTNU;2019:347, Doctoral thesis, 2019)Installing wind turbine blades is a highly demanding task due to their large lifting height and the requirements of high precision. The single blade installation method – where individual blades are lifted using a jack-up ... -
Numerical Study on Offshore Wind Turbine Blade Installation by Utilizing a Floating Vessel
Jæger, Bjørn Wilhelm (Master thesis, 2021)Når vindturbininstallasjoner til havs beveger seg mot dypere vann, blir det mer utfordrende for det konvensjonelle oppjekkningsfartøyet å utføre installasjonene. Flytende fartøy kan utføre operasjoner uavhengig av dybde, ... -
Offshore wind turbine operations and maintenance: A state-of-the-art review
Ren, Zhengru; Verma, Amrit Shankar; Li, Ye; Teuwen, Julie J.E.; Jiang, Zhiyu (Peer reviewed; Journal article, 2021)Operations and maintenance of offshore wind turbines (OWT) play an important role in the development of offshore wind farms. Compared with operations, maintenance is a critical element in the levelized cost of energy, given ... -
Response-Based Assessment of Operational Limits for Mating Blades on Monopile-Type Offshore Wind Turbines
Verma, Amrit Shankar; Jiang, Zhiyu; Ren, Zhengru; Gao, Zhen; Vedvik, Nils Petter (Journal article; Peer reviewed, 2019)Installation of wind-turbine blades on monopile-type offshore wind turbines is a demanding task. Typically, a jack-up crane vessel is used, and blades are individually lifted from the vessel deck and docked with the ... -
Sea state estimation based on vessel motion responses: Improved smoothness and robustness using Bezier surface and L1 optimization
Ren, Zhengru; Han, Xu; Verma, Amrit Shankar; Dirdal, Johann Alexander; Skjetne, Roger (Peer reviewed; Journal article, 2021)Floating structures oscillate in waves, where these wave-induced motions may be critical for various marine operations. An important consideration is thereby given to the sea states at the planning and operating stages for ... -
Structural Safety Assessment of Marine Operations From a Long-Term Perspective: A Case Study of Offshore Wind Turbine Blade Installation
Verma, Amrit Shankar; Gao, Zhen; Jiang, Zhiyu; Ren, Zhengru; Vedvik, Nils Petter (Chapter, 2019)A marine operation is a complex non-routine activity of limited duration carried out in offshore environment. Due to safety reasons, these operations are normally performed within specific sea state limits, which are derived ...