The hydrodynamic performance of a dual-rotor horizontal axis marine turbine (HAMCT) is investigated for the power gain in operating the rear rotor without blade-pitch control. This kind of turbine can be advantageous for a rectilinear tidal current of reversing directions, where each rotor blade is optimally fixed-pitched towards its upstream velocity. The blade element momentum (BEM) method is coupled with the Park wake model. A generic three-blade turbine is shown to gain up to 20% in the coefficient of power CP as relative to the front rotor CP when operating the rear rotor at the same tip speed ratio (TSR) as the front one, gaining overall CP up to 0.55. Analytic model is derived to backup the estimate of power gain. Plots for turbine performance variation with TSR and profile hydrodynamic efficiency are given, and analysed for lab and small-medium size turbines.

Nithya Venkatesan

Electrical

School of Electrical Engineering

Chennai Campus

Avital E.J

Ai K

Samad A

Korakianitis T.

Fulltext

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

&nbsp;

&nbsp;

VIT University

International Journal of Engineering & Technology

The increasing demand for electricity is the biggest alarm of the nations all over the world. These demands can be reached by using the non-polluting renewable resources and one such is ocean energy, which is still being explored. This paper analyses the flow through a turbine used in a tidal energy harvesting plant. The turbine used is a horizontal axis current turbine with three blades mounted to the hub. The Reynolds-averaged Navier-Stokes equation is solved to get the flow field and turbine performance using a commercial package Ansys CFX 15.0. The results are compared with the existing experimental results. The performance of the turbine can be improved by changing its vital parameters like hub pitch angle, inlet velocity, rotational speed and etc. Working on these turbine parameters, a set of power coefficient data are given for various tip speed ratio. © 2016 Taylor & Francis Group, London.

Progress in Renewable Energies Offshore

Parametric analysis of a tidal current turbine using CFD techniques

The effect of surface waves on the hydrodynamic performance of a marine current turbine (MCT) is studied using the unsteady BEM method. The calculation are found to be in a very good agreement with experimental results of a small scale MCT. It is shown that a large amplitude wave, but still a long wave can affect the time-averaged coefficient of power and also introduce non-linearity in the time response of the turbine particularly at low tip speed ratio. This can have consequence for an effective control of the turbine. Instantaneous blade loading and power spectra are given and analyzed. © 2016 IEEE.

Proceedings of 2016 7th International Conference on Mechanical and Aerospace Engineering, ICMAE 2016

Surface wave effect on marine current turbine, modelling and analysis

Marine tidal energy extraction faces multi-fold challenges during design, installation, operation and grid-connection. The control of turbine speed with tidal variation is vital to get a steady power output from the turbines during the operation phase throughout the year. This paper deals with the development and implementation of a control strategy for a horizontal axis turbine using the Blade Element Momentum (BEM) approach as the hydrodynamic model and generator (DFIG) control. A control efficiency of 71% is achieved between the system's overall and the hydrodynamic power of a small scale turbine. It is also shown that the generator speed can be well maintained to operate in a super-synchronous mode. © 2016 IEEE.

Modeling and controller implementation of tidal turbine for Indian remote islands

Transactions on Engineering Technologies

The Surface Curvature Effect on Performance of a Laboratory Scale Tidal Turbine

International Journal of Mechanical Engineering and Robotics Research

CFD Analysis for the Performance of Gurney Flap on Aerofoil and Vertical Axis Turbine

Hydrodynamic Assessment of a Dual-Rotor Horizontal Axis Marine Current Turbine

Journal	International Journal of Engineering & Technology
Publisher	Science Publishing Corporation
ISSN	2227524X
Open Access	Yes