scholarly journals Feasibility Study of Monsoon Effect on Wave Power for Wave Energy Converter in Sabah, Malaysia

2021 ◽  
Vol 10 (2) ◽  
pp. 396-403
Author(s):  
Nur Syafiqa Aifa Shahrom ◽  
Md Naiem Mohd Azzeri ◽  
Mohd Shukri Yusop ◽  
Mohd Norsyarizad Razali ◽  
Mohd Najib Bin Abdul Ghani Yolhamid ◽  
...  
Keyword(s):  
Wave Height ◽  
Wave Energy ◽  
Coastal Area ◽  
Acoustic Doppler Current Profiler ◽  
Southwest Monsoon ◽  
Wave Period ◽  
Wave Power ◽  
Northeast Monsoon ◽  
Height Range ◽  
The Difference

This paper presents a research to determine the effects of the Northeast Monsoon (NEM) and the Southwest Monsoon (SWM) on wave power along the coastal area of Mandi Darah Island, Sabah. This study identified the daily data of wave height and wave period for 6 months from June to December 2018. The following period was chosen because it consisted of two monsoon seasons in Sabah. The data obtained from the Acoustic Doppler Current Profiler (ADCP) were thoroughly analyzed to estimate the wave height and the wave period to identify the wave power at Mandi Darah Island. The wave heights ranged from 0.01 m to 0.47 m while the wave periods ranged from 1.0 s to 8.6 s. The wave height range during the NEM was higher by 0.12 m than SWM, while the difference of wave period was significantly higher by 2.17 s during the NEM. The maximum wave power recorded at Mandi Darah Island was 1.57 kW/m throughout the period. During NEM, the wave power was significantly higher than during SWM, by 0.70 kW/m. These findings led to determining the wave energy type converter that suits the wave conditions at the Mandi Darah Island coastal area.

scholarly journals Kajian Energi Gelombang Laut Di Daerah Abrasi Serangai, Bengkulu Utara Melalui Pengamatan Tinggi Gelombang Laut

2021 ◽  
Vol 11 (2) ◽  
pp. 143
Author(s):  
Ashar Muda Lubis ◽  
Yosi Apriani Putri ◽  
Rio Saputra ◽  
Juhendi Sinaga ◽  
M Hasanudin ◽  
...  
Keyword(s):  
Wave Height ◽  
Wave Energy ◽  
Seasonal Variations ◽  
Coastal Area ◽  
Significant Wave Height ◽  
Ocean Waves ◽  
Wave Period ◽  
Maximum Wave Height ◽  
Significant Wave ◽  
Sea Wave

<p class="AbstractText"><span lang="EN-AU">The Serangai area, Batik Nau District, North Bengkulu has the highest average abrasion speed of 20 m/year. The abrasion could cause the coastal area to erode the coastline till several tens of meters. The purpose of this study was to determine the height of the ocean waves and to determine the energy of the ocean waves that has the potential to accelerate the abrasion process in the Serangai area. The research was carried out on November 5-7, 2018 in the Serangai beach area at a depth of 5 m using SBE 26 Plus Seagauge Wave equipment. The results showed that the observed wave height was between 0.8-1.6 m with a significant wave height (Hs) of 1.38 m. In addition, the wave period ranges from 5-11 s with a significant wave period (Ts) of 8.2 s. The result also shows that the maximum wave height of 1.6 m occurred on November 7, 2018 with maximum wave energy of 1800 J/m<sup>2</sup>. This result can perhaps accelerate the abrasion process in the Serangai area. It can also be seen that the wave height in the Serangai region is higher than in several other areas in Indonesia. However, it is necessary to continue observing the wave height to see the seasonal variations in sea wave height in Serangai area.</span></p>

The Open Sea Tests of the Offshore Floating Type Wave Power Device “Mighty Whale”: Performance of the Prototype

2002 ◽  
Author(s):  
Teruhisa Ogata ◽  
Yukihisa Washio ◽  
Hiroyuki Osawa ◽  
Yasushi Tsuritani ◽  
Seiya Yamashita ◽  
...  
Keyword(s):  
Wave Height ◽  
Wave Energy ◽  
Wave Period ◽  
Power Device ◽  
Design Stage ◽  
Wave Power ◽  
Significant Wave ◽  
Type Wave ◽  
Open Sea ◽  
Floating Type

This paper presents the characteristics of wave conditions, wave energy absorption, response of hull-motion and wave height dissipation based on the results of the open sea tests. 0.5–1.0m of significant wave height and 6–7 seconds of significant wave period appear the most predominant, and average wave energy is estimated 4.88kW/m around the test site. Average power output for the test is approximately 6kWh and the maximum total energy efficiency is around 15% that is ranging from 6–7 seconds of significant wave period. Slow drift oscillation of hull was observed motion in surge, sway and yaw and the value of its amplitude almost equal to estimated values in design stage. Then the mean value of transmission coefficient is about 0.8 under 8.0 seconds of significant wave period. We are considering that the results of the tests should be useful for optimum design of an offshore floating type wave power device.

UNDERWATER BARRED BEACH PROFILE TRANSFORMATION UNDER DIFFERENT WAVES CONDITIONS

2017 ◽  
Author(s):  
Olga Kuznetsova ◽  
Olga Kuznetsova ◽  
Yana Saprykina ◽  
Yana Saprykina ◽  
Boris Divinsky ◽  
...  
Keyword(s):  
Numerical Modelling ◽  
Coastal Zone ◽  
Wave Height ◽  
Wave Energy ◽  
Wave Period ◽  
Beach Profile ◽  
Infragravity Waves ◽  
Wave Parameters ◽  
Mean Wave Period

Based on numerical modelling evolution of beach under waves with height 1,0-1,5 m and period 7,5 and 10,6 sec as well as spectral wave parameters varying cross-shore analysed. The beach reformation of coastal zone relief is spatially uneven. It is established that upper part of underwater beach profile become terraced and width of the terrace is in direct pro-portion to wave height and period on the seaward boundary but inversely to angle of wave energy spreading. In addition it was ascertain that the greatest transfiguration of profile was accompanied by existence of bound infragravity waves, smaller part of its energy and shorter mean wave period as well as more significant roller energy.

scholarly journals Physical Modelling of the Effect on the Wave Field of the WaveCat Wave Energy Converter

2021 ◽  
Vol 9 (3) ◽  
pp. 309
Author(s):  
James Allen ◽  
Gregorio Iglesias ◽  
Deborah Greaves ◽  
Jon Miles
Keyword(s):  
Wave Height ◽  
Wave Energy ◽  
Significant Wave Height ◽  
Wedge Angle ◽  
Wave Energy Converter ◽  
Wave Period ◽  
Surface Elevation ◽  
Energy Converter ◽  
Significant Wave ◽  
Model Scale

The WaveCat is a moored Wave Energy Converter design which uses wave overtopping discharge into a variable v-shaped hull, to generate electricity through low head turbines. Physical model tests of WaveCat WEC were carried out to determine the device reflection, transmission, absorption and capture coefficients based on selected wave conditions. The model scale was 1:30, with hulls of 3 m in length, 0.4 m in height and a freeboard of 0.2 m. Wave gauges monitored the surface elevation at discrete points around the experimental area, and level sensors and flowmeters recorded the amount of water captured and released by the model. Random waves of significant wave height between 0.03 m and 0.12 m and peak wave periods of 0.91 s to 2.37 s at model scale were tested. The wedge angle of the device was set to 60°. A reflection analysis was carried out using a revised three probe method and spectral analysis of the surface elevation to determine the incident, reflected and transmitted energy. The results show that the reflection coefficient is highest (0.79) at low significant wave height and low peak wave period, the transmission coefficient is highest (0.98) at low significant wave height and high peak wave period, and absorption coefficient is highest (0.78) when significant wave height is high and peak wave period is low. The model also shows the highest Capture Width Ratio (0.015) at wavelengths on the order of model length. The results have particular implications for wave energy conversion prediction potential using this design of device.

scholarly journals Wave Energy Assessment in the Bohai Sea and the Yellow Sea Based on a 40-Year Hindcast

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2087
Author(s):  
Jie Dong ◽  
Jian Shi ◽  
Jianchun Zhao ◽  
Chi Zhang ◽  
Haiyan Xu
Keyword(s):  
Wave Height ◽  
Wave Energy ◽  
Yellow Sea ◽  
Significant Wave Height ◽  
Bohai Sea ◽  
The Yellow Sea ◽  
Wave Power ◽  
Power Flux ◽  
Significant Wave ◽  
The Bohai Sea

A wave hindcast, covering the period of 1979–2018, was preformed to assess wave energy potential in the Bohai Sea and the Yellow Sea. The hindcase was carried out using the third generation wave model TOMAWAC with high spatio-temporal resolution (about 1 km and on an hourly basis). Results show that the mean values of significant wave height increase from north to south, and the maximum values are located at the south part of the Yellow Sea with amplitude within 1.6 m. The magnitudes of significant wave height values vary significantly within seasons; they are at a maximum in winter. The wave energy potential was represented by distributions of the wave power flux. The largest values appear in the southeast part of the numerical domain with wave power flux values of 8 kW/m. The wave power flux values are less than 2 kW/m in the Bohai Sea and nearshore areas of the Yellow Sea. The seasonal mean wave power flux was found up to 8 kW/m in the winter and autumn. To investigate the exploitable wave energy, a wave energy event was defined based on the significant wave height (Hs) threshold values of 0.5 m. The wave energy in south part of the Yellow Sea is more steady and intensive than in the other areas. Wave energy in winter is more suitable for harvesting wave energy. Long-term trends of wave power availability suggest that the values of wave power slightly decreased in the 1990s, whereas they have been increasing since 2006.

Performance assessments of the fully submerged sphere and cylinder point absorber wave energy converters

2019 ◽  
Vol 33 (13) ◽  
pp. 1950168 ◽  
Author(s):  
Qianlong Xu ◽  
Ye Li ◽  
Yingkai Xia ◽  
Weixing Chen ◽  
Feng Gao
Keyword(s):  
Wave Height ◽  
Wave Energy ◽  
Interaction Analysis ◽  
Wave Power ◽  
Viscous Damping ◽  
Power Performance ◽  
Point Absorber ◽  
Wave Energy Converters ◽  
Submerged Sphere ◽  
Energy Converters

Fully submerged sphere and cylinder point absorber (PA), wave energy converters (WECs) are analyzed numerically based on linearized potential flow theory. A boundary element method (BEM) (a radiation–diffraction panel program for wave-body interactions) is used for the basic wave-structure interaction analysis. In the present numerical model, the viscous damping is modeled by an equivalent linearized damping which extracts the same amount of wave energy over one cycle as the conventional quadratic damping term. The wave power capture width in each case is predicted. Comparisons are also made between the sphere and cylinder PAs which have identical geometrical scales and submerged depths. The results show that: (i) viscous damping has a greater influence on wave power performance of the cylinder PA than that of the sphere PA; (ii) the increasing wave height reduces wave power performance of PAs; (iii) the cylinder PA has a better wave power performance compared to the sphere PA in larger wave height scenarios, which indicates that fully submerged cylinder PA is a preferable prototype of WEC.

Basic Characteristics of the Primary Conversion of an OWC Type WEC Installed on a Wave Dissipating Double-Caisson

2018 ◽  
Author(s):  
Tomoki Ikoma ◽  
Koichi Masuda ◽  
Hiroaki Eto ◽  
Shogo Shibuya
Keyword(s):  
Wave Height ◽  
Basic Property ◽  
Wave Energy ◽  
Wave Power ◽  
Oscillating Water Column ◽  
Type Wave ◽  
Wave Energy Converters ◽  
The World ◽  
Fixed Type ◽  
Basic Characteristics

Several types of oscillating water column (OWC) type wave energy converters (WECs) are researched and developed in the world. They are floating types and fixed types. In case of a fixed type, wave dissipating caissons could be replaced to WECs of an OWC type. On OWC types, installation of the projecting-walls (PWs) is useful in order to improve PTO performance. In this study, it was considered that a double dissipating caisson was used as an OWC type WEC with PWs. A front caisson of the double caisson seems the area surrounded by PWs and a back caisson can be seen as an OWC. The paper studied basic property of the primary conversion from wave power to power of air from model tests in a wave tank. As a result, wave height strongly effects on behaviours of OWC motion as well as air pressure. Finally, the primary conversion was affected by wave height. Besides, the concept of use of a double caisson was useful from the primary conversion over 80 % evaluated using test data.

scholarly journals Occurrence features of Rip current at Ha My (Dien Ban district) and Tam Thanh (Tam Ky city) beaches, Quang Nam province

2019 ◽  
Vol 19 (4A) ◽  
pp. 43-53
Author(s):  
Le Dinh Mau ◽  
Nguyen Van Tuan ◽  
Nguyen Chi Cong ◽  
Tran Van Binh ◽  
Pham Ba Trung ◽  
...  
Keyword(s):  
Wave Energy ◽  
Surf Zone ◽  
Transition Period ◽  
Current System ◽  
Southwest Monsoon ◽  
Northeast Monsoon ◽  
Rip Current ◽  
Rip Currents ◽  
Open Sea ◽  
Study Results

Rip current is a relatively strong, narrow current flowing outward from the beach through the surf zone and presenting a hazard to swimmers. This paper presents some occurrence features of Rip current at main swimming beaches in Quang Nam province, Central Vietnam. Study results show that most of swimming beaches along Quang Nam province coast are directly opposed to open sea and strongly affected by swell. Therefore, Rip current system can occur at any time in the year with large dimension and intensity. During Northeast monsoon (November to March) beach morphology is considerably changed by strong wave action, thus the strongest rip current is formed. However, in this period careful swimmers can easily identify where that rip current occurs along the beach. During the transition period from Northeast monsoon to Southwest monsoon (April to May) wave energy is reduced, thus Rip current intensity is also decreased. During Southwest monsoon (June to August) wave energy is not strong and beach is accreted, therefore some Rip currents remain at reasonable morphology places along the beach. During the transition period from Southwest monsoon to Northeast monsoon (September to October) Rip current can occur at deep places along the beach with characteristics of narrow dimension, thus causing more danger to swimmer. Especially, dangerous rip current is caused by swell which comes from active region of tropical cyclone in open sea. In this period wave field in the nearshore region is not rough, thus most of swimmers are not cautious when swimming at dangerous rip current places.

scholarly journals Oscillating wave energy power generator for lift net fishing boat

2019 ◽  
Vol 13 (1) ◽  
pp. 354
Author(s):  
Luther Sule ◽  
Parabelem Tinno Dolf Rompas
Keyword(s):  
Wave Height ◽  
Wave Energy ◽  
Diesel Engines ◽  
Wave Power ◽  
Fishing Vessel ◽  
Power Generator ◽  
Fishing Boat ◽  
Sufficient Power ◽  
Height Data

This paper compares several designs of an oscillating wave power generator suitable for local net fishing boat in the waters of Tonyaman in the Strait of Makassar, Indonesia.  The designs were based on wave height data for the period of January to December 2016 and of the local fishing vessel construction data. Several generator designs were created to replace diesel engines used by the local fishermen to power their boats’ lamps in the night. Results showed that DESIGN 5 with Arm length to buoy (<em>L</em><sub>1</sub>) of 4 m and Arm length to pulley (<em>L</em><sub>2</sub>) of 3 m and DESIGN 6 with  <em>L</em><sub>1</sub> of 4 m and <em>L</em><sub>2</sub> of 2 m were the two designs most fitting for that purpose. Both designs could produce sufficient power ( ) to power the boats’ lamps in the shortest wave height condition (0.75 m) and the tallest wave height condition (1.5 m). At the shortest wave height condition (0.75 m), DESIGN 5 produced 14,237.58 W and DESIGN 6 produced 14,290.31 W. At the tallest wave height condition (1.5 m), DESIGN 5 and DESIGN 6 generated 28,285.31 W and 28,496.25 W of power, respectively.

scholarly journals Optimization of an Invention Based on a Force Multiplier Mechanism for Wave Power Generation

2014 ◽  
Vol 507 ◽  
pp. 480-485
Author(s):  
Javier Aparisi ◽  
Jose González ◽  
Bernabé Hernandis
Keyword(s):  
Power Generation ◽  
Wave Height ◽  
Wave Energy ◽  
Fossil Fuels ◽  
Clean Energy ◽  
Wave Energy Converter ◽  
Wave Power ◽  
Rectilinear Motion ◽  
Energy Converter ◽  
The Waves

The development and exploitation of new sources of clean energy that do not depend on traditional sources based on the use of fossil fuels, is the focus of this research, which starts with the optimization of an invention capable of transforming a reciprocating rectilinear motion into continuous circular motion in a very efficient way, to be used in the development of a Wave Energy Converter (WEC), capable of operating with low wave height and taking advantage of the oscillating movement of the waves both when rising, and when lowering, unlike other similar devices that harness it only in one way.

Sign in / Sign up

Export Citation Format

Share Document