Study on calculation method of incident wave power of irregular wave for wave energy conversion model systems

2020 ◽  
Author(s):  
Lu Kuan ◽  
Wang Huamei ◽  
Han Linsheng ◽  
Rao Xiang
Keyword(s):  
Energy Conversion ◽  
Incident Wave ◽  
Wave Energy ◽  
Calculation Method ◽  
Model Systems ◽  
Wave Power ◽  
Wave Energy Conversion ◽  
Conversion Model ◽  
Irregular Wave

scholarly journals The Development of Wave Energy Conversion Device to Generate Electricity

2015 ◽  
Vol 773-774 ◽  
pp. 460-464 ◽  
Author(s):  
M.D. Lafsah ◽  
Mohd Zamri Ibrahim ◽  
Aliashim Albani
Keyword(s):  
Energy Conversion ◽  
Wave Energy ◽  
Power Device ◽  
Wave Power ◽  
Wave Energy Conversion ◽  
Electric Generator ◽  
Measurement Results ◽  
Conversion System ◽  
Energy Conversion System ◽  
Final System

The wave energy is one of promising resource for generating electricity in this country. A wave energy conversion system was designed and fabricated; the prototype was tested and its performance was analyzed. The invention herein proposed a system operated by wave resource. This configuration allows the wave resource working to generate electricity. Wave power device operated by the movement of floaters with varying speed connected to the mechanical racks. These mechanical racks move gears and pulleys, which giving forces to the pulley’s belts to rotate. This pulley’s belts connected to the electric generator that produces the electricity. The final system was tested in the coastal area near to Universiti Malaysia Terengganu (UMT) campus. The measurement results clearly show that the available wave resource could be harness into useful work for electric power generation.

scholarly journals ESTIMATION OF THE WAVE POWER POTENTIAL IN COASTAL REGIONS OF FLORIDA

2018 ◽  
pp. 98
Author(s):  
Cigdem Ozkan ◽  
Talea L. Mayo
Keyword(s):  
Energy Conversion ◽  
Wave Energy ◽  
The United States ◽  
Wave Power ◽  
Renewable Energy Resources ◽  
Wave Energy Conversion ◽  
Coastal Regions ◽  
Ocean Wave Energy ◽  
Wave Power Potential ◽  
Energy Conversion Devices

The state of Florida has an abundance of renewable energy resources. Florida sees sun in an average 60% of its available daylight hours, and has 8,436 miles of coastline, and thus solar and wave energy are two promising alternatives to more conventional energy sources. The Electric Power Research Institute estimates the wave power potential along the Gulf of Mexico coast and East coast of the United States as 60 TWh/year and 160 TWh/year, respectively. One TWh/year can power approximately 93,850 US homes annually, and thus it is likely that ocean wave energy has the potential to greatly contribute to the overall energy supply. This can be acheived by harnessing and converting wave energy into electricity using wave energy conversion devices. However, the feasibility of wave energy conversion must be assessed before such technologies can be employed. As a first step, the amount of available wave power in regions where devices may be deployed should be estimated. In this study, we assess the wave power potential of Florida’s nearshore coastal regions.

scholarly journals Air Turbines for Wave Energy Conversion

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Manabu Takao ◽  
Toshiaki Setoguchi
Keyword(s):  
Energy Conversion ◽  
Wave Energy ◽  
Cross Flow ◽  
Wave Energy Conversion ◽  
Wells Turbine ◽  
Impulse Turbine ◽  
Sea Trial ◽  
Irregular Wave ◽  
Wave Conditions ◽  
Starting Characteristics

This paper describes the present status of the art on air turbines, which could be used for wave energy conversion. The air turbines included in the paper are as follows: Wells type turbines, impulse turbines, radial turbines, cross-flow turbine, and Savonius turbine. The overall performances of the turbines under irregular wave conditions, which typically occur in the sea, have been compared by numerical simulation and sea trial. As a result, under irregular wave conditions it is found that the running and starting characteristics of the impulse type turbines could be superior to those of the Wells turbine. Moreover, as the current challenge on turbine technology, the authors explain a twin-impulse turbine topology for wave energy conversion.

A Sea Trial of Wave Power Plant With Impulse Turbine

2008 ◽  
Author(s):  
Manabu Takao ◽  
Eiji Sato ◽  
Shuichi Nagata ◽  
Kazutaka Toyota ◽  
Toshiaki Setoguchi
Keyword(s):  
Power Plant ◽  
Energy Conversion ◽  
Wave Energy ◽  
Rotational Speed ◽  
Guide Vane ◽  
Wave Power ◽  
Wave Energy Conversion ◽  
Wells Turbine ◽  
Impulse Turbine ◽  
Sea Trial

A sea trial of wave power plant using an impulse turbine with coreless generator has been carried out at Niigata-nishi Port, in order to demonstrate usefulness of the turbine for wave energy conversion. Oscillating water column (OWC) based wave power plant has been installed at the side of a breakwater and has an air chamber with a sectional area of 4 m2 (= 2m × 2m). The impulse turbine used in the sea trial has fixed guide vanes both upstream and downstream, and these geometries are symmetrical with respect to the rotor centerline in order to rotate in a single direction in bi-directional airflow generated by OWC. The turbine is operated at lower rotational speed in comparison with conventional turbines. The rotor has a tip diameter of 458 mm, a hub-to-tip ratio of 0.7, a tip clearance of 1 mm, a chord length of 82.8 mm and a solidity of 2.0. The guide vane with chord length of 107.4 mm is symmetrically installed at the distance of 30.7 mm downstream and upstream of the rotor. The guide vane has a solidity of 2.27, a thickness ratio of 0.0279, a guide vane setting angle of 30° and a camber angle of 60°. The generator is coreless type and can generate electricity at lower rotational speed in comparison with conventional generator. The rated and maximum powers of the generator are 450 W and 880 W respectively. The experimental data obtained in the sea trial of wave power plant with the impulse turbine having coreless generator was compared to these of Wells turbine which is the mainstream of the turbine for wave energy conversion. As a result, total efficiency of the plant using the impulse turbine was higher than that of Wells turbine.

scholarly journals Hydrodynamic Performance of an Asymmetry OWC Device Mounted on a Box-Type Breakwater

2021 ◽  
Vol 8 ◽  
Author(s):  
Zhengzhi Deng ◽  
Pinjie Wang ◽  
Pengda Cheng
Keyword(s):  
Energy Conversion ◽  
Wave Height ◽  
Incident Wave ◽  
Wave Energy ◽  
Short Wave ◽  
Absorption Efficiency ◽  
Hydrodynamic Performance ◽  
Maintenance Cost ◽  
Wave Energy Conversion ◽  
Coupling System

To share the construction and maintenance cost, an asymmetric oscillating water column (OWC) device integrated with a pile-fixed box-typed offshore breakwater is considered experimentally and numerically. A fully nonlinear numerical wave tank is established and validated with the open source solver OpenFOAM. The effects of the width and draft of rear box, and the incident wave height on the wave energy conversion efficiency, reflection and transmission coefficients, and energy dissipation coefficient are examined. In addition, the superiority of the present coupling system, compared to the traditional box-type breakwater, is discussed. With well comparisons, the results show that the existence of the rear breakwater is beneficial for the formation of partial standing waves and further wave energy conversion. In the range of wave heights tested, the higher the incident wave height, the larger the energy absorption efficiency except for the short-wave regimes. Moreover, the OWC-breakwater coupling system can obtain a similar wave blocking ability to the traditional one, and simultaneously extract wave energy and decrease wave reflection.

Wave Power for U.S. Coast Guard First District Lighthouses

Solar Energy ◽  
2005 ◽  
Author(s):  
Andy Walker ◽  
Alicen Kandt ◽  
Donna Heimiller
Keyword(s):  
Energy Conversion ◽  
Wave Energy ◽  
Alternative Energy ◽  
Energy Content ◽  
Energy Resource ◽  
Coast Guard ◽  
Wave Power ◽  
Wave Energy Conversion ◽  
Submarine Cables ◽  
Conversion Technologies

Lighthouses and other navigational aids are situated near tumultuous seas and thus may be good candidates for early applications of wave energy conversion technologies. The U.S. Coast Guard First District is converting lighthouses’ electrical systems to solar power to divest itself of electrical submarine cables and overhead costs associated with cable maintenance. However, in some lighthouses solar conversion is impractical or may compromise historic preservation. Unless alternative energy sources become available for these locations, they will continue to use submarine cables to run on shore power. Lighthouse sites for which shoreline and wave characteristics are suitable would be good candidates for a wave energy demonstration project. This paper describes gravity wave physics and the characteristics of mechanical radiation (growth, propagation, diffraction, and shoaling). A simple expression for energy content of a wave train with a two-parameter Bretschneider spectrum is applied to spectral wave density data collected from 15 buoys to evaluate wave energy resource potential at 31 candidate lighthouse sites in New England. Annual average wave power per meter of wavecrest varied from 3.9 to 21.7 kW/m at the buoys, and from 3.9 to 9.2 kW/m (with an average of 5.0 kW/m) at the lighthouses (buoys with maximum wave power are far out to sea, but still influence the correlation). The performance characteristics of two types of wave energy conversion technologies are used to calculate annual energy delivery by way of example. The paper concludes with a discussion of economics and environmental and permitting issues. It identifies Seguin Island light off a point in Maine and Nauset Beach, Chatham, Nantucket, and Sankaty Head lights (on Nantucket Island and along the outer shore of Cape Cod) as the best sites to begin more detailed evaluations, based on a comparison of wave power and utility rates. Subsequent studies would include demand profile for lighthouses, supply profiles, and resulting storage requirements.

scholarly journals Influence of the Number of Coil on the Accelerated-Type Wave Energy Generation System

2021 ◽  
Vol 252 ◽  
pp. 02079
Author(s):  
Hu Chen ◽  
Zhifei Ji ◽  
sheng Hu ◽  
Min Lin
Keyword(s):  
Power Generation ◽  
Energy Conversion ◽  
Wave Energy ◽  
Electrical Energy ◽  
Wave Power ◽  
Linear Wave ◽  
Wave Energy Conversion ◽  
Generation System ◽  
Power Generation System ◽  
Wave Power Generation

This paper proposed a pulley-buoy accelerated type linear wave power generation system, and verifies its feasibility and effectiveness through experiments. Compared with traditional three-phase wave energy converter, the process of energy transfer was cancelled in the pulley-buoy accelerated type linear wave power generation system, wave energy was converted into electrical energy through the movement of float directly. In the system, the pulley assembly increased the velocity of the float and the generating capacity of the linear generation system, thereby increasing its conversion efficiency. In the experiment, an undersized pulley-buoy accelerated type linear wave power generation system and a swing wave-making system were built in the laboratory. The experiment explored the influence of the number of the stator coil on the power generation performance of the system, and results showed that within the scope of this research, increasing the stator coils to a certain extent could effectively raise the efficiency of wave energy conversion and improve the generation performance of the pulley-buoy accelerated type linear wave power generation system. This research provides valuable experience for the actual application and effective operation of wave energy conversion system.

scholarly journals Fundamental formulae for wave-energy conversion

2015 ◽  
Vol 2 (3) ◽  
pp. 140305 ◽  
Author(s):  
Johannes Falnes ◽  
Adi Kurniawan
Keyword(s):  
Energy Conversion ◽  
Wave Energy ◽  
Reactive Power ◽  
Oscillation Amplitude ◽  
Wave Power ◽  
Wave Energy Conversion ◽  
Average Maximum ◽  
Absorbed Power ◽  
Time Average ◽  
Average Wave

The time-average wave power that is absorbed from an incident wave by means of a wave-energy conversion (WEC) unit, or by an array of WEC units—i.e. oscillating immersed bodies and/or oscillating water columns (OWCs)—may be mathematically expressed in terms of the WEC units' complex oscillation amplitudes, or in terms of the generated outgoing (diffracted plus radiated) waves, or alternatively, in terms of the radiated waves alone. Following recent controversy, the corresponding three optional expressions are derived, compared and discussed in this paper. They all provide the correct time-average absorbed power. However, only the first-mentioned expression is applicable to quantify the instantaneous absorbed wave power and the associated reactive power. In this connection, new formulae are derived that relate the ‘added-mass’ matrix, as well as a couple of additional reactive radiation-parameter matrices, to the difference between kinetic energy and potential energy in the water surrounding the immersed oscillating WEC array. Further, a complex collective oscillation amplitude is introduced, which makes it possible to derive, by a very simple algebraic method, various simple expressions for the maximum time-average wave power that may be absorbed by the WEC array. The real-valued time-average absorbed power is illustrated as an axisymmetric paraboloid defined on the complex collective-amplitude plane. This is a simple illustration of the so-called ‘fundamental theorem for wave power’. Finally, the paper also presents a new derivation that extends a recently published result on the direction-average maximum absorbed wave power to cases where the WEC array's radiation damping matrix may be singular and where the WEC array may contain OWCs in addition to oscillating bodies.

Sign in / Sign up

Export Citation Format

Share Document