WindFloat: A Floating Foundation for Offshore Wind Turbines—Part II: Hydrodynamics Analysis

2009 ◽  
Author(s):  
Christian Cermelli ◽  
Dominique Roddier ◽  
Alexia Aubault
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Hydrodynamic Model ◽  
Offshore Wind ◽  
Scale Model ◽  
Hydrodynamic Analysis ◽  
Offshore Wind Turbines ◽  
Floating Foundation ◽  
Ongoing Work ◽  
Aerodynamic Simulation

WindFloat is a floating foundation for very large offshore wind turbines. This paper describes the hydrodynamic analysis of the hull, as well as ongoing work consisting of coupling hull hydrodynamics with wind-turbine aerodynamic forces. Three main approaches are presented in this paper: - The numerical hydrodynamic model of the platform and its mooring system; - Wave tank testing of a scale model of the platform with simplified aerodynamic simulation of the wind turbine; - FAST, an aerodynamic software package for wind turbine analysis with the ability to be coupled to the hydrodynamic model. These conference proceedings include two other papers presenting the design basis and main systems of this floating foundation [1], as well as structural analysis of the hull and mast [2].

PyraWind™: An Innovative Floating Offshore Wind Turbine (FOWT) Global Performance Analysis

2021 ◽  
Author(s):  
Zhiyong Yang ◽  
Xiaoqiang Bian ◽  
Yu Shi
Keyword(s):  
Wind Turbine ◽  
Hydrodynamic Model ◽  
Coupled System ◽  
Offshore Wind ◽  
Offshore Wind Turbine ◽  
Floating Offshore Wind Turbine ◽  
Offshore Wind Turbines ◽  
Ongoing Work ◽  
Heavy Lift ◽  
Solid Foundation

Abstract In the near future, the offshore wind industry will experience a significant increase of turbine size and of floating wind development activities. A floating offshore wind turbine foundation offers many advantages, such as flexibility in site selection, access to better offshore wind resources, and quayside integration to avoid a costly heavy lift vessel offshore campaign. PyraWind™ is a patented three canted column semisubmersible floating foundation for ultra large offshore wind turbines. It is designed to accommodate a wind turbine, 14 MW or larger, in the center of the interconnected columns of the hull with minimal modifications to the tower, nacelle and turbine. The pyramid-shaped hull provides a stable, solid foundation for the large wind turbine under development. This paper summarizes the feasibility study conducted for the PyraWind™ concept. The design basis for wind turbine floating foundations is described and the regulatory requirements are discussed. Also included are the hydrodynamic analysis of the hull and ongoing work consisting of coupling hull hydrodynamics with wind-turbine aerodynamic loads. The fully coupled system was analyzed using OpenFAST, an aerodynamic software package for wind turbine analysis with the ability to be coupled with the hydrodynamic model. Due to the canted columns, a nonlinear analysis was performed using the coupled numerical hydrodynamic model of the platform with mooring system in extreme sea states.

Advanced Concept Offshore Wind Turbine Development

2014 ◽  
Vol 18 (5) ◽  
pp. 728-735 ◽  
Author(s):  
Abdollah A. Afjeh ◽  
◽  
Brett Andersen ◽  
Jin Woo Lee ◽  
Mahdi Norouzi ◽  
...  
Keyword(s):  
Wind Energy ◽  
Wind Turbine ◽  
Wind Turbines ◽  
Cost Savings ◽  
Offshore Wind ◽  
Offshore Wind Turbine ◽  
Offshore Wind Energy ◽  
Offshore Wind Turbines ◽  
Floating Foundation ◽  
The Cost

Development of novel offshore wind turbine designs and technologies are necessary to reduce the cost of offshore wind energy since offshore wind turbines need to withstand ice and waves in addition to wind, a markedly different environment from their onshore counterparts. This paper focuses on major design challenges of offshore wind turbines and offers an advanced concept wind turbine that can significantly reduce the cost of offshore wind energy as an alternative to the current popular designs. The design consists of a two-blade, downwind rotor configuration fitted to a fixed bottom or floating foundation. Preliminary results indicate that cost savings of nearly 25% are possible compared with the conventional upwind wind turbine designs.

WindFloat: A Floating Foundation for Offshore Wind Turbines—Part I: Design Basis and Qualification Process

2009 ◽  
Author(s):  
Dominique Roddier ◽  
Christian Cermelli ◽  
Alla Weinstein
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Oil And Gas ◽  
Large Diameter ◽  
Offshore Wind ◽  
Site Location ◽  
Offshore Wind Turbines ◽  
Design Basis ◽  
Floating Foundation ◽  
Visual Impacts

This paper and the corresponding hydrodynamic and structural study paper (also in these proceedings) summarize the feasibility study conducted for the WindFloat technology. The WindFloat is a 3-legged floating foundation for very large offshore wind turbines. It is designed to accommodate a wind turbine, 5 MW or larger, on one of the columns of the hull with minimal modifications to the tower, nacelle and turbine. Technologies for floating foundations for offshore wind turbines are evolving. It is agreed by most experts that the offshore wind industry will see a significant increase in activity in the near future. Fixed offshore turbines are limited in water depth to approximately 30∼50m. Market transition to deeper waters is inevitable, provided suitable technologies can be developed. Despite the increase in complexity, a floating foundation offers distinct advantages: • Flexibility in site location. • Access to superior wind resources further offshore. • Ability to locate in coastal regions with limited shallow continental shelf. • Ability to locate further offshore to eliminate visual impacts. • An integrated structure, without a need to redesign the mast foundation connection for every project. • Simplified offshore installation procedures. Anchors are significantly cheaper to install than fixed foundations and large diameter towers. This paper focuses on the design basis for wind turbine floating foundations, and explores the requirements that must be addressed by design teams in this new field. It shows that the design of the hull for a large wind turbine must draw on the synergies with oil and gas offshore platform technology, while accounting for the different design requirements and functionality of the wind turbine.

scholarly journals A 6-DOFs Hardware-in-the-Loop System for Wind Tunnel Tests of Floating Offshore Wind Turbines

2019 ◽  
Author(s):  
Alessandro Fontanella ◽  
Ilmas Bayati ◽  
Federico Taruffi ◽  
Francesco La Mura ◽  
Alan Facchinetti ◽  
...  
Keyword(s):  
Wind Tunnel ◽  
Wind Turbine ◽  
Wind Turbines ◽  
Offshore Wind ◽  
Scale Model ◽  
Hardware In The Loop ◽  
Floating Platform ◽  
Wind Tunnel Tests ◽  
Offshore Wind Turbines ◽  
Floating Offshore Wind Turbines

Abstract This article presents a hardware-in-the-loop (HIL) methodology developed at Politecnico di Milano (PoliMi) to perform wind tunnel tests on floating offshore wind turbines (FOWTs). The 6-DOFs HIL setup is presented, focusing on the main differences with respect to a previous 2-DOFs system. Aerodynamic, rotor and control related loads, physically reproduced by the wind turbine scale model, must be measured in real-time and integrated with the platform numerical model. These forces contribute to couple wind turbine and floating platform dynamics and their correct reproduction is of fundamental importance for the correct simulation of the floating system behavior. The procedure developed to extract rotor loads from the available measurements is presented, discussing its limitations and the possible uncertainties introduced in the results. Results from verification tests in no-wind conditions are presented and analyzed to identify the main uncertainty sources and quantify their effect on the reproduction of the floating wind turbine response to combined wind and waves.

Control of Floating Offshore Wind Turbines: Reduced-Order Modeling and Real-Time Implementation for Wind Tunnel Tests

2018 ◽  
Author(s):  
Alessandro Fontanella ◽  
Ilmas Bayati ◽  
Marco Belloli
Keyword(s):  
Wind Tunnel ◽  
Wind Turbine ◽  
Wind Turbines ◽  
Offshore Wind ◽  
Scale Model ◽  
System Response ◽  
Wind Tunnel Tests ◽  
Reduced Order ◽  
Offshore Wind Turbines ◽  
Floating Offshore Wind Turbines

The present work deals with the implementation of a variable-speed variable-pitch control strategy on a wind turbine scale model for hybrid/HIL wind tunnel tests on floating offshore wind turbines. The effects that scaling issues, due to low-Reynolds aerodynamics and rotor structural properties, have in combination with the HIL technique developed by the authors are studied through a dedicated reduced-order linear coupled model. The model is used to tune the original pitch controller gains so to be able to reproduce the system response of the full-scale floating wind turbine during HIL tests.

Design and Testing of Scale Model Wind Turbines for Use in Wind/Wave Basin Model Tests of Floating Offshore Wind Turbines

2013 ◽  
Author(s):  
Matthew J. Fowler ◽  
Richard W. Kimball ◽  
Dale A. Thomas ◽  
Andrew J. Goupee
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Model Tests ◽  
Full Scale ◽  
Offshore Wind ◽  
Scale Model ◽  
Offshore Wind Turbines ◽  
Floating Offshore Wind Turbines ◽  
Wave Basin ◽  
Scale Design

Model basin testing is a standard practice in the design process for offshore floating structures and has recently been applied to floating offshore wind turbines. 1/50th scale model tests performed by the DeepCwind Consortium at Maritime Research Institute Netherlands (MARIN) in 2011 on various platform types were able to capture the global dynamic behavior of commercial scale model floating wind turbine systems; however, due to the severe mismatch in Reynolds number between full scale and model scale, the strictly Froude-scaled, geometrically similar wind turbine underperformed greatly. This required significant modification of test wind speeds to match key wind turbine aerodynamic loads, such as thrust. To execute more representative floating wind turbine model tests, it is desirable to have a model wind turbine that more closely matches the performance of the full scale design. This work compares the wind tunnel performance, under Reynolds numbers corresponding to model test Froude-scale conditions, of an alternative wind turbine designed to emulate the performance of the National Renewable Energy Laboratory (NREL) 5 MW turbine. Along with the test data, the design methodology for creating this wind turbine is presented including the blade element momentum theory design of the performance-matched turbine using the open-source tools WT_Perf and XFoil. In addition, a strictly Froude-scale NREL 5 MW wind turbine design is also tested to provide a basis of comparison for the improved designs. While the improved, performance-matched turbine was designed to more closely match the NREL 5 MW design in performance under low model test Reynolds numbers, it did not maintain geometric similitude in the blade chord and thickness orientations. Other key Froude scaling parameters, such as blade lengths and rotor operational speed, were maintained for the improved designs. The results of this work support the development of protocols for properly designing scale model wind turbines that emulate the full scale design for Froude-scale wind/wave basin tests of floating offshore wind turbines.

Designing Process and Motion Characteristics of Spar Type Offshore Wind Turbines

2013 ◽  
Author(s):  
Yasunori Nihei ◽  
Tomoki Ikoma ◽  
Minori Kozen ◽  
Fumiya Sato ◽  
Motohiko Murai ◽  
...  
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Oil And Gas ◽  
Type Structure ◽  
Offshore Wind ◽  
Scale Model ◽  
Offshore Wind Turbine ◽  
Offshore Wind Turbines ◽  
Motion Characteristics

In this paper, we will discuss about the designing process and the motion characteristics of the spar type offshore wind turbines. When considering a spar type structure for offshore wind turbines, it is important to take a lot of elements into consideration which have not yet been considered in the case of oil and gas platforms. In this research, we used the following standards to conduct our tests. The limit of the heel angle was 5 degrees when the wind turbines are generating in the rated state. When designing the substructure for this research we have decided to go with a substructure that operates in depth of 100m or more. Following the conditions above we have designed the spar type offshore wind turbine used for this research. In order to compare the simulated result we have created a scale model and performed tank tests under various conditions. Also we observed unexpected motion characteristics in certain mooring arrangement. So we will touch these subjects in this paper.

WindFloat: A Floating Foundation for Offshore Wind Turbines—Part III: Structural Analysis

2009 ◽  
Author(s):  
Alexia Aubault ◽  
Christian Cermelli ◽  
Dominique Roddier
Keyword(s):  
Wind Turbines ◽  
Structural Engineering ◽  
Structural Response ◽  
Offshore Wind ◽  
Design Teams ◽  
Hydrodynamic Analysis ◽  
Offshore Wind Turbines ◽  
Floating Foundation ◽  
Experimental Validations ◽  
Related Paper

WindFloat is a floating foundation for large offshore wind turbines. This paper describes the structural engineering that was performed as part of the feasibility study conducted for qualification of the technology. Specifically, the preliminary scantling is described and the strength and fatigue analysis methodologies are explained, focusing on the following aspects: • the coupling between the wind turbine and the hull; • the interface between the hydrodynamic loading and the structural response. Prior to reading this manuscript, the reader is strongly encouraged to read the related paper, which focuses on the design basis for the WindFloat, and explores the requirements that must be addressed by the design teams in this new field. An additional paper in this series describes the hydrodynamic analysis and experimental validations.

scholarly journals Improving the Strategy of Maintaining Offshore Wind Turbines through Petri Net Modelling

2021 ◽  
Vol 11 (2) ◽  
pp. 574
Author(s):  
Rundong Yan ◽  
Sarah Dunnett
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Petri Net ◽  
Offshore Wind ◽  
Offshore Wind Turbine ◽  
Maintenance Costs ◽  
Offshore Wind Turbines ◽  
Major Repair ◽  
Wind Turbine System ◽  
Periodic Maintenance

In order to improve the operation and maintenance (O&M) of offshore wind turbines, a new Petri net (PN)-based offshore wind turbine maintenance model is developed in this paper to simulate the O&M activities in an offshore wind farm. With the aid of the PN model developed, three new potential wind turbine maintenance strategies are studied. They are (1) carrying out periodic maintenance of the wind turbine components at different frequencies according to their specific reliability features; (2) conducting a full inspection of the entire wind turbine system following a major repair; and (3) equipping the wind turbine with a condition monitoring system (CMS) that has powerful fault detection capability. From the research results, it is found that periodic maintenance is essential, but in order to ensure that the turbine is operated economically, this maintenance needs to be carried out at an optimal frequency. Conducting a full inspection of the entire wind turbine system following a major repair enables efficient utilisation of the maintenance resources. If periodic maintenance is performed infrequently, this measure leads to less unexpected shutdowns, lower downtime, and lower maintenance costs. It has been shown that to install the wind turbine with a CMS is helpful to relieve the burden of periodic maintenance. Moreover, the higher the quality of the CMS, the more the downtime and maintenance costs can be reduced. However, the cost of the CMS needs to be considered, as a high cost may make the operation of the offshore wind turbine uneconomical.

scholarly journals Impact of Typhoons on Floating Offshore Wind Turbines: A Case Study of Typhoon Mangkhut

2021 ◽  
Vol 9 (5) ◽  
pp. 543
Author(s):  
Jiawen Li ◽  
Jingyu Bian ◽  
Yuxiang Ma ◽  
Yichen Jiang
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Safety Evaluation ◽  
Offshore Wind ◽  
Offshore Wind Turbine ◽  
Motion Response ◽  
Offshore Wind Turbines ◽  
Floating Offshore Wind Turbines ◽  
Coupling Motion

A typhoon is a restrictive factor in the development of floating wind power in China. However, the influences of multistage typhoon wind and waves on offshore wind turbines have not yet been studied. Based on Typhoon Mangkhut, in this study, the characteristics of the motion response and structural loads of an offshore wind turbine are investigated during the travel process. For this purpose, a framework is established and verified for investigating the typhoon-induced effects of offshore wind turbines, including a multistage typhoon wave field and a coupled dynamic model of offshore wind turbines. On this basis, the motion response and structural loads of different stages are calculated and analyzed systematically. The results show that the maximum response does not exactly correspond to the maximum wave or wind stage. Considering only the maximum wave height or wind speed may underestimate the motion response during the traveling process of the typhoon, which has problems in guiding the anti-typhoon design of offshore wind turbines. In addition, the coupling motion between the floating foundation and turbine should be considered in the safety evaluation of the floating offshore wind turbine under typhoon conditions.

Sign in / Sign up

Export Citation Format

Share Document