Hydrodynamics of a Raft-Type Device with Water Tanks

  • Siming ZhengEmail author
Part of the Springer Theses book series (Springer Theses)


In this chapter, to seek new ways of improving the power capture capacity of raft-type device, a novel two-raft wave energy absorption device is proposed and investigated with a numerical method. The novel device consists of two hinged cylindrical rafts of elliptical cross section with water tanks inside and a Power Take-Off (PTO) system at the joint. As the two rafts rotate in ocean waves, the water in the internal tanks oscillates at the same time. Meanwhile, the wave-induced relative rotation of the rafts is resisted by the PTO system to capture wave power. To study the hydrodynamics of the raft-type device with water tanks, the dynamic coupling between liquid motions in the tanks (sloshing) and rigid body motions of the hinged rafts (seakeeping) in frequency is considered, based on the three-dimensional wave radiation-diffraction theory. Effects of damping of PTO system, and the size and position of the tanks on dynamics of the device mainly in terms of wave energy absorption are investigated.


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© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Tsinghua UniversityBeijingChina

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