Projects per year
Abstract / Description of output
There are a wide range of applications in which it is desirable to mitigate unsteady load fluctuations while preserving mean loading. This is often achieved with active control systems, but passive systems are sometimes more desirable for enhancing reliability. This is the case, for example, for wind and tidal turbines, where unsteady loading limits the fatigue life of the turbine and results in power peaks at the generator. Here, we consider the unsteady load mitigation that can be achieved through a foil with a trailing-edge flap that is connected to the foil via a torsional spring. We develop a theoretical model and show that the preload can be tuned to preserve the mean foil loading. The spring moment that maximises the unsteady load mitigation is approximately constant, and the load fluctuation reduction is linearly proportional to the ratio of the flap to the full chord of the foil. We verify this relationship through water tunnel tests of a foil with a hinge at 25% of the chord from the trailing edge. As theoretically predicted, we measure unsteady load mitigation of up to 25%, without any variation in the mean load. In highly unsteady flow conditions, when boundary layer separation occurs, the unsteady load reduction decreases. Overall we conclude that passive trailing-edge flaps are effective in alleviating unsteady load fluctuations and their effectiveness depends on their size relative to the foil.
Original language | English |
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Article number | 103352 |
Journal | Journal of fluids and structures |
Volume | 106 |
Early online date | 18 Aug 2021 |
DOIs | |
Publication status | Published - Oct 2021 |
Keywords / Materials (for Non-textual outputs)
- Load alleviation
- Passive trailing-edge flap
- Tidal energy
- Unsteady aerodynamics
- Unsteady loading
Fingerprint
Dive into the research topics of 'Unsteady load mitigation through a passive trailing-edge flap'. Together they form a unique fingerprint.Projects
- 3 Finished
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Centre for Advanced Materials for Renewable Energy Generation
Robertson, N., Campbell, E. & Mount, A.
1/12/16 → 31/05/21
Project: Research
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United Kingdom Centre for Marine Energy Research
Wallace, R., Ingram, D., Jeffrey, H. & Kiprakis, A.
1/10/16 → 31/05/19
Project: Research
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Flexible-Blades: Flow control to mitigate fatigue load through the use of flexible tidal turbine blades
Viola, I. M., Richon, J., Tully, S., Arredondo, A., Le Mestre, R. & Muir, R.
1/10/14 → 30/06/15
Project: Research
Research output
- 2 Article
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Mitigation of Rotor Thrust Fluctuations through Passive Pitch
Dai, W., Broglia, R. & Viola, I. M., Jul 2022, In: Journal of fluids and structures. 112, 103599.Research output: Contribution to journal › Article › peer-review
Open AccessFile -
Morphing Blades for Tidal Turbines: a Theoretical Study
Pisetta, G., Le Mestre, R. & Viola, I. M., 1 Jan 2022, In: Renewable Energy. 183, p. 802-819Research output: Contribution to journal › Article › peer-review
Open AccessFile
Datasets
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Passively morphing trailing-edges for load alleviation in tidal turbines
Arredondo Galeana, A. (Creator), Smyth, A. (Creator), Young, A. (Creator) & Viola, I. M. (Creator), Edinburgh DataShare, 3 Aug 2020
DOI: 10.7488/ds/2878
Dataset