The University of Southampton
University of Southampton Institutional Repository

Performance prediction of a free stream tidal turbine with composite bend-twist coupled blades

Record type: Conference or Workshop Item (Poster)

Free stream tidal turbines are a source of growing interest in the marine renewable energy field. Some designs use variable pitch blade control devices in order to maximize the efficiency of the turbines; however these are complex to design, construct and maintain under the severe load conditions sub sea devices experience. There is an interest in the use of composite materials for potential improvements in hydrodynamic and structural performance of Horizontal Axis Tidal Turbines (HATT). In addition to the advantages of high strength-to-mass and high strength to stiffness ratios, anisotropy of the laminated fibre composites can be designed to allow 3D tailoring of the blade deformation. Anisotropic structures show different levels of elastic coupling, depending on the ply angle in the layers that comprise such a material. Passive control of a turbine blade can be achieved by taking advantage of the directionality of the anisotropic composite material. A structure that undergoes both bending and twisting due to a pure bending load is said to exhibit bend-twist coupling. This type of behaviour has been identified as a potential method for load reduction - particularly fatigue loads, and an increase in both efficiency and annual energy capture in wind turbines [1]. Preliminary studies have since shown that this may also be the case for HATTs [2]. A computationally efficient, yet realistic, model has been developed in order to estimate the amount of induced twist present on a bend-twist coupled blade in a tidal stream. This model takes into account the effect on the induced twist of fibre orientation, blade loading and cross section, material mechanical properties, and shell thickness. The method has been incorporated into a Blade Element Momentum code, modified to predict the performance of free stream tidal devices; such that the performance of a HATT with composite bend-twist coupled blades could be estimated. It has been shown that, when compared to a free stream tidal turbine with fixed blades of a similar configuration, a HATT that utilises composite bend-twist couple blades can reduced fatigue loading, bring the turbine efficiency closer to the Betz limit and increase the annual energy capture.

PDF ICOE_2008_paper_corrected.pdf - Other
Download (393kB)

Citation

Nicholls-Lee, R.F., Turnock, S.R. and Boyd, S.W. (2008) Performance prediction of a free stream tidal turbine with composite bend-twist coupled blades At 2nd International Conference on Ocean Energy (ICOE 2008). 15 - 17 Oct 2008. 9 pp.

More information

Published date: 15 October 2008
Venue - Dates: 2nd International Conference on Ocean Energy (ICOE 2008), 2008-10-15 - 2008-10-17
Related URLs:
Organisations: Fluid Structure Interactions Group

Identifiers

Local EPrints ID: 66466
URI: http://eprints.soton.ac.uk/id/eprint/66466
PURE UUID: 5213e41f-aa17-42c9-821c-6c89d5cb597d
ORCID for S.R. Turnock: ORCID iD orcid.org/0000-0001-6288-0400

Catalogue record

Date deposited: 19 Jun 2009
Last modified: 19 Jul 2017 00:24

Export record

Contributors

Author: R.F. Nicholls-Lee
Author: S.R. Turnock ORCID iD
Author: S.W. Boyd

University divisions


Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×