Tide, Wave and Hydro Power
Hosein Jokar; Abuzar Abazari; Reza Dorostkar
Abstract
One of the main needs for dhow vessels is fuel for diesel generators that generate electricity, which in turn is used in refrigerators and electronic devices. Concerning the development of new devices for electricity generation such as point absorber wave energy converters, in the present research for ...
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One of the main needs for dhow vessels is fuel for diesel generators that generate electricity, which in turn is used in refrigerators and electronic devices. Concerning the development of new devices for electricity generation such as point absorber wave energy converters, in the present research for the first time, the feasibility of installing such converters on the hull of the dhow vessel and their performance is being examined. These WECs expanded on the sea-free surface level during anchoring time. Depending on the relative angular displacement between the WEC and the dhow hull the electricity is produced. In the present study, the simulations are done based on the diffraction theory in Ansys AQWA. The results showed that for considering four installed WECs, the maximum output power of 400 kilowatts is produced, which is an acceptable amount of energy for supplying the common electronic devices on the dhow vessel. In addition to this, it has been shown that the hybrid system of the dhow and WECs in the anchoring mode has fewer dynamic responses compared to a single dhow without WECs. Such conditions can be utilized for the comfort of the passengers or special operations during the anchoring time. It was also observed that the buoy size does not have a considerable effect on the production power and dynamic response of the platform, while the length of 2 m for the lever and angle of 90 degrees of the incident wave is optimum from the production power point of view.
A. Abazari; M.M. Aziminia
Abstract
Flap-type wave energy converter is one of the oscillating surge devices for generating electricity from the ocean wave source. It comprises a vertical plate pivoted on a hinged base that oscillates rotationally due to the exciting wave. Splitting a single flap into two separated flaps in a double arrangement ...
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Flap-type wave energy converter is one of the oscillating surge devices for generating electricity from the ocean wave source. It comprises a vertical plate pivoted on a hinged base that oscillates rotationally due to the exciting wave. Splitting a single flap into two separated flaps in a double arrangement may cause different dynamic characteristics. This can improve the output extracted power versus the excitation period. Therefore, this effect is investigated in the present study through a dynamic mathematical model. The hydrodynamic coefficients and exciting torques in the equation are calculated based on the Boundary Element-based software of ANSYS AQWA. In the next step, the rotational displacement is calculated through the frequency domain approach based on the assumption of the regular monochromatic and head-on waves, and consequently, the maximum power is computed regarding the optimum power take-off damping strategy. Finally, in the same procedure as the single flap, the output power for the double arrangement is derived. The results show that decreasing the natural period for each flap can potentially cause a wideband response of the total power for the double configuration compared to the single one.
Tide, Wave and Hydro Power
A. Abazari
Abstract
The combination of offshore wind turbines and wave energy converters has recently been the focus of researchers. Many types of converters have been installed on the offshore platform in the design step, and the performance of these hybrid systems has been investigated. The oscillating water column converter ...
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The combination of offshore wind turbines and wave energy converters has recently been the focus of researchers. Many types of converters have been installed on the offshore platform in the design step, and the performance of these hybrid systems has been investigated. The oscillating water column converter is one of the most favorite and commercialized systems due to its efficiency and low maintenance cost. In the present study, a new design including the array of the oscillating water column in a circular arrangement around the spar-type platform is considered. The coupled governing equations are solved based on the simplified analytical approach through frequency domain analysis. The results show that the increase in the number of energy converters increases the total generated power, and consequently, the converters capture the vibrational energy of the spar platform. Therefore, the dynamic response of the spar decreases in the case with an array of energy converters which is one of the main objects of this hybrid system.