ON THE DESIGN OF A PROTOTYPE MODEL OF THE FLOATING WAVE POWER DEVICE "MIGHTY WHALE"
H. Hotta, Y. Washio, H. Yokozawa &D. J Pizer, JAMSTEC, Yokosuka, Japan
ABSTRACT
The "Mighty Whale" is a floating wave power device to convert the wave energy to other convenient energy for the conservation of the sea, and to create the calm sea area such as a floating breakwater. JAMSTEC (Japan Marine Science and Technology Center) is promoting the R&D on this "Mighty Whale" since 1986. Already, we finished fundamental development by theoretical, numerical and experimental study on the basic "Mighty Whale". By 1996, we will finish to design the prototype model of the "Mighty Whale', will start to construct it afterwards, and will carry out the open sea test between 1998 and 1999 at the coastal sea of Japan.
The dimensions of the "Mighty Whale" are 50m in length, 30m in breadth and it has 3 air chambers, 3 units of the air turbines and generators of 50 kW rated power. It will be moored by mooring chains and anchors at the site of about 35m water depth.
The mechanism to absorb the wave energy is of the OWC (Oscillating Water Column) type with the Wells Turbine. As some results of the study up to this time, its efficiency to absorb the wave energy is about 40-50% in average in regular waves, and it can make in the lee zone the height of incident waves about one half under 8 sec of the significant wave period. Because of such behavior, and from the view point of "sustainable development" at the coastal zone, we recognize the "Mighty Whale" can be a convenient and beneficial structure for the coastal development.
In this paper, we introduce this design and behavior, and discuss the utilization of the "Mighty Whale" for the coastal development.
