Experimental Study of Wave Force Distribution on a Monopile Structure
As the demand for offshore wind energy continues to grow, the strive to understand the wave forces acting on the substructure of the wind turbines continues. In regard to wind turbine design, it is vital to consider not only the total wave force, but also the local wave forces. Local forces are part...
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American Society of Mechanical Engineers
2018
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ftdtupubl:oai:pure.atira.dk:publications/f6574092-b5a1-4b5e-ad67-f2024dd28244 2024-02-11T09:59:40+01:00 Experimental Study of Wave Force Distribution on a Monopile Structure Vested, Malene Hovgaard Carstensen, Stefan Christensen, Erik Damgaard 2018 https://orbit.dtu.dk/en/publications/f6574092-b5a1-4b5e-ad67-f2024dd28244 https://doi.org/10.1115/OMAE2018-77509 eng eng American Society of Mechanical Engineers https://orbit.dtu.dk/en/publications/f6574092-b5a1-4b5e-ad67-f2024dd28244 urn:ISBN:978-0-7918-5127-2 info:eu-repo/semantics/closedAccess Vested , M H , Carstensen , S & Christensen , E D 2018 , Experimental Study of Wave Force Distribution on a Monopile Structure . in ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering . vol. 7B: Ocean Engineering , OMAE2018-77509 , American Society of Mechanical Engineers , 37th International Conference on Ocean, Offshore and Artic Engineering (OMAE2018) , Madrid , Spain , 17/06/2018 . https://doi.org/10.1115/OMAE2018-77509 contributionToPeriodical 2018 ftdtupubl https://doi.org/10.1115/OMAE2018-77509 2024-01-24T23:58:33Z As the demand for offshore wind energy continues to grow, the strive to understand the wave forces acting on the substructure of the wind turbines continues. In regard to wind turbine design, it is vital to consider not only the total wave force, but also the local wave forces. Local forces are particularly important for the design of secondary structures as e.g. mooring platforms. Typically, however, experimental studies mainly concern total forces or idealized local forces. We present here a rather simple way to measure local forces along a model monopile. The study is conducted in a wave flume of 28 m in length, in which waves are generated by a piston-type wave maker at a water depth of 0.515 m and shoal onto a bed of slope 1:25. A model monopile is installed and subjected to forcing from a series of both regular and irregular waves. In the experimental set-up, the model monopile is fixed at the bottom and the top and consists of seven independent cylindrical sections. The cylindrical sections are connected by force transducers which measure local shear, and so the associated local forces may be determined. The measured local forces are compared to the force distribution given by Morisons equation combined with linear theory and Wheeler stretching, which is a force estimate commonly used in the industry. This study shows that the total force is rather well captured by Morison’s equation. The force distribution estimated from Morison’s equation, however, shows larger discrepancies from the measured forces. This encourages for further measurements. In this study, we show that it is possible to measure force distribution on a model monopile in a simple and cost-effective manner. The aim is here to demonstrate the method and we will later present a larger body of work associated with the outcome of the measurements. Article in Journal/Newspaper Arctic Technical University of Denmark: DTU Orbit Volume 7B: Ocean Engineering |
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Open Polar |
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Technical University of Denmark: DTU Orbit |
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ftdtupubl |
language |
English |
description |
As the demand for offshore wind energy continues to grow, the strive to understand the wave forces acting on the substructure of the wind turbines continues. In regard to wind turbine design, it is vital to consider not only the total wave force, but also the local wave forces. Local forces are particularly important for the design of secondary structures as e.g. mooring platforms. Typically, however, experimental studies mainly concern total forces or idealized local forces. We present here a rather simple way to measure local forces along a model monopile. The study is conducted in a wave flume of 28 m in length, in which waves are generated by a piston-type wave maker at a water depth of 0.515 m and shoal onto a bed of slope 1:25. A model monopile is installed and subjected to forcing from a series of both regular and irregular waves. In the experimental set-up, the model monopile is fixed at the bottom and the top and consists of seven independent cylindrical sections. The cylindrical sections are connected by force transducers which measure local shear, and so the associated local forces may be determined. The measured local forces are compared to the force distribution given by Morisons equation combined with linear theory and Wheeler stretching, which is a force estimate commonly used in the industry. This study shows that the total force is rather well captured by Morison’s equation. The force distribution estimated from Morison’s equation, however, shows larger discrepancies from the measured forces. This encourages for further measurements. In this study, we show that it is possible to measure force distribution on a model monopile in a simple and cost-effective manner. The aim is here to demonstrate the method and we will later present a larger body of work associated with the outcome of the measurements. |
format |
Article in Journal/Newspaper |
author |
Vested, Malene Hovgaard Carstensen, Stefan Christensen, Erik Damgaard |
spellingShingle |
Vested, Malene Hovgaard Carstensen, Stefan Christensen, Erik Damgaard Experimental Study of Wave Force Distribution on a Monopile Structure |
author_facet |
Vested, Malene Hovgaard Carstensen, Stefan Christensen, Erik Damgaard |
author_sort |
Vested, Malene Hovgaard |
title |
Experimental Study of Wave Force Distribution on a Monopile Structure |
title_short |
Experimental Study of Wave Force Distribution on a Monopile Structure |
title_full |
Experimental Study of Wave Force Distribution on a Monopile Structure |
title_fullStr |
Experimental Study of Wave Force Distribution on a Monopile Structure |
title_full_unstemmed |
Experimental Study of Wave Force Distribution on a Monopile Structure |
title_sort |
experimental study of wave force distribution on a monopile structure |
publisher |
American Society of Mechanical Engineers |
publishDate |
2018 |
url |
https://orbit.dtu.dk/en/publications/f6574092-b5a1-4b5e-ad67-f2024dd28244 https://doi.org/10.1115/OMAE2018-77509 |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
Vested , M H , Carstensen , S & Christensen , E D 2018 , Experimental Study of Wave Force Distribution on a Monopile Structure . in ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering . vol. 7B: Ocean Engineering , OMAE2018-77509 , American Society of Mechanical Engineers , 37th International Conference on Ocean, Offshore and Artic Engineering (OMAE2018) , Madrid , Spain , 17/06/2018 . https://doi.org/10.1115/OMAE2018-77509 |
op_relation |
https://orbit.dtu.dk/en/publications/f6574092-b5a1-4b5e-ad67-f2024dd28244 urn:ISBN:978-0-7918-5127-2 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1115/OMAE2018-77509 |
container_title |
Volume 7B: Ocean Engineering |
_version_ |
1790595457993408512 |