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Computational Assessment of a Modular Composite Wind Turbine Blade Joint
Pages 76-90

Norimichi Nanami and Ozden O. Ochoa

DOI: http://dx.doi.org/10.6000/1929-6002.2016.05.03.1

Published: 07 November 2016

 

Abstract: Wind energy is one of the most promising and mature alternatives to satisfy the global demand for energy as the world population and the economic activity surge. The wind energy market has grown rapidly in the last couple of decades, boosting up the size of wind turbines to generate higher power output. Typically, the larger/longer blade designs rely on hybrid material systems such as carbon and/or glass fiber (CF/GF) reinforced polymers to improve specific stiffness/strength and damage tolerance.

Herein, we propose a computational design concept for a modular hybrid composite wind turbine blade that maintains its structural integrity and serviceability requirements. The modular configuration will simplify manufacturing-assembly processes and reduce expenses both in transportation and facilities requirements. The 80 m blade in this study is composed of two sections that are joined together with an innovative compression joint. Our results when compared to a single continuous blade, showed no significant alterations to its structural response. It is concluded that the proposed computational design concept that allow two modular blades to create full-length blade with robust joints is achievable. This modular concept can be easily extended for further multi-section modular blade configurations.

Keywords: Finite element analysis, Joining design concept, Structural response, Hybrid composite materials, Large-scale wind turbine blades.
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Numerical and Experimental Test on an Innovative Device Based on Multiple Rotors in Line to Tap Clean Energy from Tidal and River Current
Pages 91-98

D.P. Coiro, F. Scherillo, G. Troise, N. Bizzarrini and G.Calise

DOI: http://dx.doi.org/10.6000/1929-6002.2016.05.03.2

Published: 07 November 2016

 

Abstract: The main object of this paper is to present the design and the results of an experimental test campaign on an innovative device for the exploitation of marine and river currents. The basic idea is to lay together one or more series of horizontal axis turbines in rows, each one connected to a generator placed on board a ship or a float. The whole system is sustained by a series of buoys, in this way is possible to avoid expensive submarine installations. All the work has been carried out at the Department of Industrial Engineering of the University of Naples “Federico II” and the test campaign has been first performed in the naval towing tank belonging to the same Department and then in real conditions in Messina Strait between Sicily island and mainland. This location is the only one in Italy suitable as test site thanks to a highly regular tidal current reaching a maximum speed of 3 m/s. The turbine’s blade was first carefully designed with particular care for the cavitation problems. Two different series of experimental tests on a reduced scale model in the naval tank aimed to optimize the general layout of the device and the tests performed in Messina Strait mainly aimed to confirm the feasibility of the system and to evaluate its response in real operating conditions. The tests have confirmed the good dynamic behavior of the whole system and its feasibility to be scaled up to real scale.

Keywords: Hydro turbines, Blade design, Floating platform, Towing tank tests, Real conditions tests.
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Joural-of-Technology-Innova smallweb

Control System for Less than Wind Turbines 1500W
Pages 99-106

D. Icaza, A. Pauta, G. Saguay and F. Solis

DOI: http://dx.doi.org/10.6000/1929-6002.2016.05.03.3

Published: 07 November 2016

 

Abstract: Using wind power generation is another alternative for remote homes, where there is no electricity grid. Especially in Ecuador there are several places where the wind resource is really stable for the year, though at times the wind regime it becomes turbulent wind speeds become quite high exceeding 12 m / s affecting the wind turbine components.

Generally in the Ecuadorian highlands are available permanent winds of medium intensity capable of generating electricity, but by having a system of turbulence for short periods of time it jeopardizes the deployed equipment and therefore the investments made by what this study guarantees the stability of small wind turbines that are very useful in our environment to generate electricity in field type housing shelters.

Keywords: Control, Wind Generators, Protection.
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Optical Response and Photovoltaic Performance of Organic Solar Cells Based on DH6T:Alq3 Active Layer
Pages 33-43
Osinowo Adekunle Ayodotun, Xiaopei Lin, Zhao Dongliang and Wang Zhifeng

DOI: http://dx.doi.org/10.6000/1929-6002.2016.05.02.1

Published: 25 July 2016

 

Abstract: This paper presents a thirty year (1976-2005) assessment of wave energy resource within the South China Sea (SCS) by simulation. Significant wave height (SWH) between simulation and observation shows good agreement. This shows the reliability of an along-side simulated wave period in estimating wave energy in the SCS. Results show that estimates of wave power density are more reliable in the north-central SCS and most sufficient during winter. The annual mean wave power density peaked at 12.7kW/m and 12.9kW/m during years 1986 and 1999 respectively while the highest seasonal mean of 29kW/m occurred in year 1999 during winter. The wave power density is most stable in winter and is generally more stable in offshore regions of SCS. Wave power density is most stable in years 1976, 1997 and 2004 with stability values of 1.96, 1.98 and 1.9 respectively. The stability value of 0.9 in year 1980 is the greatest in the winter of all years. Relative-rich energy regions occupy the largest area during winter. The relatively richest energy is generally concentrated in the central and north-central SCS. No area is identified as a relative-rich energy region during spring. Winter 1999 has the highest relative-rich energy with value of 37kW/m.

Keywords: South China Sea, Wave power density, Wave power stability, Relative-rich energy, Distribution.
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