Reliability Based Design of Fixed Foundation Wind Turbines

Reliability Based Design of Fixed Foundation Wind Turbines
Author:
Publisher:
Total Pages:
Release: 2013
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ISBN:

Recent analysis of offshore wind turbine foundations using both applicable API and IEC standards show that the total load demand from wind and waves is greatest in wave driven storms. Further, analysis of overturning moment loads (OTM) reveal that impact forces exerted by breaking waves are the largest contributor to OTM in big storms at wind speeds above the operating range of 25 m/s. Currently, no codes or standards for offshore wind power generators have been adopted by the Bureau of Ocean Energy Management Regulation and Enforcement (BOEMRE) for use on the Outer Continental Shelf (OCS). Current design methods based on allowable stress design (ASD) incorporate the uncertainty in the variation of loads transferred to the foundation and geotechnical capacity of the soil and rock to support the loads is incorporated into a factor of safety. Sources of uncertainty include spatial and temporal variation of engineering properties, reliability of property measurements applicability and sufficiency of sampling and testing methods, modeling errors, and variability of estimated load predictions. In ASD these sources of variability are generally given qualitative rather than quantitative consideration. The IEC 61400-3 design standard for offshore wind turbines is based on ASD methods. Load and resistance factor design (LRFD) methods are being increasingly used in the design of structures. Uncertainties such as those listed above can be included quantitatively into the LRFD process. In LRFD load factors and resistance factors are statistically based. This type of analysis recognizes that there is always some probability of failure and enables the probability of failure to be quantified. This paper presents an integrated approach consisting of field observations and numerical simulation to establish the distribution of loads from breaking waves to support the LRFD of fixed offshore foundations.

Reliability-Based Optimization of Floating Wind Turbine Support Structures

Reliability-Based Optimization of Floating Wind Turbine Support Structures
Author: Mareike Leimeister
Publisher: Springer Nature
Total Pages: 336
Release: 2023-01-01
Genre: Technology & Engineering
ISBN: 3030968898

This book pursues the ambitious goal of combining floating wind turbine design optimization and reliability assessment, which has in fact not been done before. The topic is organized into a series of very ambitious objectives, which start with an initial state-of-the-art review, followed by the development of high-fidelity frameworks for a disruptive way to design next generation floating offshore wind turbine (FOWT) support structures. The development of a verified aero-hydro-servo-elastic coupled numerical model of dynamics for FOWTs and a holistic framework for automated simulation and optimization of FOWT systems, which is later used for the coupling of design optimization with reliability assessment of FOWT systems in a computationally and time-efficient manner, has been an aim of many groups internationally towards implementing a performance-based/goal-setting approach in the design of complex engineering systems. The outcomes of this work quantify the benefits of an optimal design with a lower mass while fulfilling design constraints. Illustrating that comprehensive design methods can be combined with reliability analysis and optimization algorithms towards an integrated reliability-based design optimization (RBDO) can benefit not only the offshore wind energy industry but also other applications such as, among others, civil infrastructure, aerospace, and automotive engineering.

Design of Foundations for Offshore Wind Turbines

Design of Foundations for Offshore Wind Turbines
Author: Subhamoy Bhattacharya
Publisher: John Wiley & Sons
Total Pages: 392
Release: 2019-03-01
Genre: Technology & Engineering
ISBN: 1119128153

Comprehensive reference covering the design of foundations for offshore wind turbines As the demand for “green” energy increases the offshore wind power industry is expanding at a rapid pace around the world. Design of Foundations for Offshore Wind Turbines is a comprehensive reference which covers the design of foundations for offshore wind turbines, and includes examples and case studies. It provides an overview of a wind farm and a wind turbine structure, and examines the different types of loads on the offshore wind turbine structure. Foundation design considerations and the necessary calculations are also covered. The geotechnical site investigation and soil behavior/soil structure interaction are discussed, and the final chapter takes a case study of a wind turbine and demonstrates how to carry out step by step calculations. Key features: New, important subject to the industry. Includes calculations and case studies. Accompanied by a website hosting software and data files. Design of Foundations for Offshore Wind Turbines is a must have reference for engineers within the renewable energy industry and is also a useful guide for graduate students in this area.

Structural Integrity of Offshore Wind Turbines

Structural Integrity of Offshore Wind Turbines
Author: Transportation Research Board
Publisher: National Academies Press
Total Pages: 109
Release: 2011-09-02
Genre: Science
ISBN: 0309225159

TRB Special Report 305: Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation explores the U.S. Department of the Interior's Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE) approach to overseeing the development and safe operation of wind turbines on the outer continental shelf, with a focus on structural safety. The committee that developed the report recommended that in order to facilitate the orderly development of offshore wind energy and support the stable economic development of this nascent industry, the United States needs a set of clear requirements that can accommodate future design development. The report recommends that BOEMRE develop a set of requirements that establish goals and objectives with regard to structural integrity, environmental performance, and energy generation. The committee found that the risks to human life and the environment associated with offshore wind farms are substantially lower than for other industries such as offshore oil and gas, because offshore wind farms are primarily unmanned and contain minimal quantities of hazardous substances. This finding implies that an approach with significantly less regulatory oversight may be taken for offshore wind farms. Under this approach, industry would be responsible for proposing sets of standards, guidelines, and recommended practices that meet the performance requirements established by BOEMRE. The domestic industry can build on standards, guidelines, and practices developed in Europe, where the offshore wind energy is further developed, but will have to fill gaps such as the need to address wave and wind loadings encountered in hurricanes. The report also includes findings and recommendations about the role that certified verification agents (third party evaluators) can play in reviewing packages of standards and project-specific proposals.

Wind Energy Systems

Wind Energy Systems
Author: John Dalsgaard Sørensen
Publisher: Elsevier
Total Pages: 621
Release: 2010-12-20
Genre: Technology & Engineering
ISBN: 0857090631

Large-scale wind power generation is one of the fastest developing sources of renewable energy and already makes a substantial contribution to power grids in many countries worldwide. With technology maturing, the challenge is now to increase penetration, and optimise the design, construction and performance of wind energy systems. Fundamental issues of safety and reliability are paramount in this drive to increase capacity and efficiency.Wind energy systems: Optimising design and construction for safe and reliable operation provides a comprehensive review of the latest developments in the design, construction and operation of large-scale wind energy systems, including in offshore and other problematic environments.Part one provides detailed coverage of wind resource assessment and siting methods relevant to wind turbine and wind farm planning, as well as aeroelastics, aerodynamics, and fatigue loading that affect the safety and reliability of wind energy systems. This coverage is extended in part two, where the design and development of individual components is considered in depth, from wind turbine rotors to drive train and control systems, and on to tower design and construction. Part three explores operation and maintenance issues, such as reliability and maintainability strategies and condition monitoring systems, before discussing performance assessment and optimisation routes for wind energy systems in low wind speed environments and cold climates. Part four reviews offshore wind energy systems development, from the impact of environmental loads such as wind, waves and ice, to site specific construction and integrated wind farm planning, and of course the critical issues and strategies for offshore operation and maintenance.With its distinguished editors and international teams of contributors, Wind energy systems is a standard reference for wind power engineers, technicians and manufacturers, as well as researchers and academics involved in this expanding field. Reviews the latest developments in the design, construction and operation of large-scale wind energy systems Offers detailed coverage of wind resource assessment and siting methods relevant to wind turbine and wind farm planning Explores operation and maintenance issues, such as reliability and maintainability strategies and condition monitoring systems

Environmental Wind Engineering and Design of Wind Energy Structures

Environmental Wind Engineering and Design of Wind Energy Structures
Author: Charalambos Baniotopoulos
Publisher: Springer Science & Business Media
Total Pages: 353
Release: 2011-12-01
Genre: Technology & Engineering
ISBN: 3709109531

The book presents a state-of-the-art in environmental aerodynamics and the structural design of wind energy support structures, particularly from a modern computational perspective. Examples include real-life applications dealing with pollutant dispersion in the building environment, pedestrian-level winds, comfort levels, relevant legislation and remedial measures. Design methodologies for wind energy structures include reliability assessment and code frameworks.