scholarly journals Risk Assessment for the Installation and Maintenance Activities of a Low-Speed Tidal Energy Converter

2012 ◽  
Author(s):  
I Lazakis ◽  
◽  
O Turan ◽  
T Rosendahl ◽  
◽  
...  
Author(s):  
Joseph MacEnri ◽  
Matthew Reed ◽  
Torbjörn Thiringer

This paper presents the analysis of the study of the flicker emitted from the 1.2 MW tidal energy converter (TEC), SeaGen, against varying tidal parameters. This paper outlines the main elements of the TEC itself, the environment it is located in and the measurement set up. In this paper, the flicker emitted by the TEC is compared with the different tidal parameters, including flood and ebb tides, tidal speed, water depth and turbulence strength and intensity. Flicker emissions have been calculated from measured data in over 90 measurement (10 min) periods, and all of the tidal parameters vary significantly over that testing period. This allows for a detailed statistical and graphical analysis of the variation of flicker with the variation of the tidal parameters outlined above. It is found, with the exception of tidal speed, that there is no strong relationship between flicker emissions and any other tidal parameter. As SeaGen is an asymmetrical TEC with full blade pitching for flood and ebb generation, it was also found that the expected difference of flicker emissions owing to the effect of the submersed crossbeam was not significant. The TEC harmonic performance versus tidal speed is also presented.


Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5145
Author(s):  
Craig Hill ◽  
Vincent S. Neary ◽  
Michele Guala ◽  
Fotis Sotiropoulos

The mechanical power and wake flow field of a 1:40 scale model of the US Department of Energy’s Reference Model 1 (RM1) dual rotor tidal energy converter are characterized in an open-channel flume to evaluate power performance and wake flow recovery. The NACA-63(4)-24 hydrofoil profile in the original RM1 design is replaced with a NACA-4415 profile to minimize the Reynolds dependency of lift and drag characteristics at the test chord Reynolds number. Precise blade angular position and torque measurements were synchronized with three acoustic Doppler velocimeters (ADV) aligned with each rotor centerline and the midpoint between the rotor axes. Flow conditions for each case were controlled to maintain a hub height velocity, uhub= 1.04 ms−1, a flow Reynolds number, ReD= 4.4 × 105, and a blade chord length Reynolds number, Rec= 3.1 × 105. Performance was measured for a range of tip-speed ratios by varying rotor angular velocity. Peak power coefficients, CP= 0.48 (right rotor) and CP= 0.43 (left rotor), were observed at a tip speed ratio, λ= 5.1. Vertical velocity profiles collected in the wake of each rotor between 1 and 10 rotor diameters are used to estimate the turbulent flow recovery in the wake, as well as the interaction of the counter-rotating rotor wakes. The observed performance characteristics of the dual rotor configuration in the present study are found to be similar to those for single rotor investigations in other studies. Similarities between dual and single rotor far-wake characteristics are also observed.


Author(s):  
Martin MOREAU ◽  
Martin TRÄSCH ◽  
Sylvain DELACROIX ◽  
Grégory GERMAIN

Author(s):  
Manh Hung Nguyen ◽  
Haechang Jeong ◽  
Changjo Yang

Renewal energy technologies are increasingly popular to ensure future energy sustainability and to balance environmental issues. The growing interest in exploring tidal energy has compelling reasons such as security and diversity of supply, intermittent but predictable and limited social and environmental impacts. The energy available in tidal currents or other artificial water channels is being considered as viable source of renewable power. Hydrokinetic conversion systems, albeit mostly at its early stage of development, may appear suitable in harnessing energy from such renewable resources. A concept of tidal energy converter (TEC) which is based on shape of the conventional water wheels, is introduced in this study. Basically, this turbine has several special features that are potentially more advantageous than the conventional tidal turbines, such as propeller type tidal turbines. The research aims to study the possibility of twelve-blade turbine in extracting the hydrokinetic energy of tidal current and converting it into electricity, and evaluate the performance of the turbine at different given arrangements of blades (single and double rows) using Computational Fluid Dynamics (CFD). In all cases of tip-speed ratio (TSR), the twelve-blade double-row type obtains higher power efficiency, especially about 20% power coefficient at TSR = 0.75, in comparison with 13% power coefficient of the single-row one. Furthermore, by changing the arrangement of rotating blades, the torque’s absorption from the rotor shaft of twelve-blade double-row turbine is more uniform due to the less interrupted and fluctuated generation of force for a period of time (one revolution of the rotor).


2012 ◽  
Vol 37 (1) ◽  
pp. 387-397 ◽  
Author(s):  
Simon P. Neill ◽  
James R. Jordan ◽  
Scott J. Couch

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