A modified Wells turbine for wave energy conversion
TL;DR: In this paper, the rotor blade pitch was set asymmetrically at a positive pitch to achieve a higher mean efficiency in a wave cycle and the performance characteristics of a turbine with different blade setting angles in steady flow were found by experimentation.
About: This article is published in Renewable Energy.The article was published on 2003-01-01. It has received 84 citations till now. The article focuses on the topics: Oscillating Water Column & Wells turbine.
Citations
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TL;DR: Shehata et al. as mentioned in this paper presented a critical appraisal of the paper "Performance analysis of Wells turbine blades using the entropy generation minimization method" by Shehata, A. S., Saqr, K. M., Xiao, Q., Shahadeh, M. F. and Day, A., published in Renewable Energy, volume 86, pp. 1123-1133.
10 citations
01 Dec 2009
TL;DR: In this paper, the potential of wave power in the Tonekabon area of Iran is assessed based on data from covering the period 2000-2007. But the authors focus on the near-shore wave field and use a wave model to select the optimum locations for a wave farm.
Abstract: Wave energy is produced when electricity generators are placed on the surface of the ocean. The energy provided is most often used in desalination plants, power plants and water pumps. Energy output is determined by wave height, wave speed, wavelength, and water density. In many areas of the world, the wind blows with enough consistency and force to provide continuous waves. There is tremendous energy in the ocean waves. Wave power devices extract energy directly from the surface motion of ocean waves or from pressure fluctuations below the surface. Tonekabon on the north of Iran is subjected to a very wave climate; in this work its potential for energy production is assessed based on data from covering the period 2000–2007. The transformation of the offshore wave field as it propagates into this area is computed by means of a near shore wave model in order to select the optimum locations for a wave farm. Zones emerge as those with the highest potential for wave energy exploitation. Wave power, along with renewable energy-generating sources like tides and streams, is underestimated considering its advantageous physical properties and predictability. This paper examines possible examples of wave power installations in the Tonekabon. The mean power within 50 km of the shore is determined to be (~ 3 kW/m), whereas higher power (~ 9 kW/m) is available further offshore.
9 citations
01 Jan 2005
9 citations
Posted Content•
TL;DR: A re-examination of the mechanisms for entropy generation in fluid flow, with a particular emphasis on RANS equations is presented, and results are verified for different flow conditions and a comparison with theoretical values are presented.
Abstract: In recent years, a number of authors have studied entropy generation in Wells turbines. This is potentially a very interesting topic, as it can provide important insights into the irreversibilities of the system, as well as a methodology for identifying, and possibly minimizing, the main sources of loss. Unfortunately, the approach used in these studies contains some crude simplifications that lead to a severe underestimation of entropy generation and, more importantly, to misleading conclusions.
This paper contains a re-examination of the mechanisms for entropy generation in fluid flow, with a particular emphasis on RANS equations. An appropriate methodology for estimating entropy generation in isolated airfoils and Wells turbines is presented. Results are verified for different flow conditions, and a comparison with theoretical values is presented.
8 citations
Cites background from "A modified Wells turbine for wave e..."
...Wells turbines have been studied extensively, both experimentally [15, 31, 24, 63, 74, 53, 57, 48] and numerically [40, 62, 17, 76, 30, 72, 32, 27], but mainly from a first-law perspective....
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TL;DR: In this paper, an optimized turbine for asymmetric airflow conditions was presented, where the rotor blade setting angle (γ) was made asymmetric with a nonzero setting angle, and the guide vane shape was optimized.
8 citations
References
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TL;DR: In this article, the performance of a single plane biplane Wells turbine with or without guide vanes is compared with a wave energy device based on the principle of the oscillating water-air column.
286 citations
TL;DR: In this article, the authors investigated the influence of the turbine aerodynamic design on the overall plant performance, as affected by the turbine peak efficiency and the range of flow rates within which the turbine can operate efficiently.
109 citations
01 Jan 2002
TL;DR: The Mighty Whale is a floating wave power device based on the Oscillating Water Column (OWC) principle, which converts wave energy into electric energy, and produces a relatively calm sea area behind.
Abstract: Mighty Whale is a floating wave power device based on the Oscillating Water Column (OWC) principle. It converts wave energy into electric energy, and produces a relatively calm sea area behind. The open sea tests were begun in September 1998 in Gokasho Bay, Nansei Town, Mie Prefecture. Measurements collected since then include performance data in typhoon seasons. This paper presents the measurements of wave energy absorption, floating body motion, and wave height dissipation. It is expected that these results will be useful in the design of offshore wave power devices in the future.
78 citations
01 Jan 2000
TL;DR: The Mighty Whale as mentioned in this paper was used for open sea tests to investigate the use of wave energy for power generation in Mie Prefecture, Japan, and the results of the tests were summarized in a recent paper.
Abstract: JAMSTEC completed the construction of the prototype device Mighty Whale by May 1998 for open sea tests to investigate practical use of wave energy. Following construction, the prototype was towed to the test location near the mouth of Gokasho Bay in Mie Prefecture. The open sea tests were begun in September 1998, after final positioning and mooring operations were completed. The tests are expected to continue for approximately 2 years. This paper presents an overview of the open sea tests, and summarizes the characteristics of power generation based on the results so far.
59 citations
Journal Article•
TL;DR: In this paper, the performance of the impulse turbine with fixed guide vanes was compared with that of the Wells turbine with a fixed guide vane, and it was shown that the running and starting characteristics of the latter were superior to those of the former under irregular wave conditions.
Abstract: The objective of this paper is to clarify the performance of impulse turbine with fixed guide vanes and to compare it with that of Wells turbine with guide vanes. As a result, a suitable choice of the design factors for the impulse turbine was shown for the inlet angle of rotor blade and the shape of guide vane. Furthermore, it was found that the running and starting characteristics of the impulse turbine were superior to those of the Wells turbine under irregular wave condition.
56 citations