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The Eagle wave energy converter (WEC) is novel device and has high power generation efficiency demonstrated by the small-scale model in the tank tests. During the sea trials of 10 kW full-scale prototype performed from 2012 to 2014, a design problem occurred that the crashworthy component (namely End Beam) was crashed up by the rotor. In order to investigate the damage mechanism of End Beam and improve the design of the Eagle WEC, an impact analysis was conducted utilizing ANSYS/LS-DYNA. In the simulation, structures were modeled as full-scale parameters and assumed to be elastic–plastic. Meanwhile, the bottoms of End Beam were presumed to be standstill. Moreover, the influences of water surrounding the WEC structures were considered using added mass method. Through the simulation, the stress and strain distributions, collision force and the energy absorption of the system were obtained. The results fit well with the actual damage situation. Furthermore, three improvement schemes were proposed including enhancing the structure of End Beam, increasing the upward angle of the rotor and adding energy accumulator. The simulation results demonstrated that the third method can effectively absorb the kinetic energy of the rotor and prevent the WEC from destruction in the rough sea states. [ABSTRACT FROM AUTHOR]

Abstract: The characteristics of host–guest complexation between hydroxypropyl-β-cyclodextrin (HP-βCD) and coumarin as well as its derivatives of 7-hydroxycoumarin (7-HC) and 6-methylcoumarin (6-MC) were investigated with phase solubility method. The investigation was carried out in water and phosphate buffer solution (pH 7.4) and at different temperatures (from 298.15K to 313.15K). The phase-solubility diagrams from UV spectral measurements were of the AL type. The solubilities of coumarin and its derivatives in aqueous HP-βCD solutions increased with temperature. The apparent stability constants (K C ) of inclusion complexes were calculated based on the solubility data and followed the order of 7-HC>6-MC>coumarin in the same solvent and at the same temperature. The stability constant of 7-HC in water was larger than that in the phosphate buffer solution, which was contrary to 6-MC and coumarin. The enthalpy and entropy changes of the inclusion process were negative, which showed that the inclusion interactions were enthalpy-driven process. All the results were interpreted with the driving forces occurred in the inclusion complexation. [Copyright &y& Elsevier]

To find an efficient and economic way to convert wave energy, a one-base multi-buoy offshore floating wave energy converter Sharp Eagle Wanshan is designed, consisting of four absorbing buoys, one semi-submersible barge, and other components. The working principle of the device is described in this paper. An experiment of a 1:13.78 model machine was carried out to test the hydrodynamic performance of the device and make an initial evaluation for the design The influence of wave period, wave height, work load and wave direction was tested. After construction, two-stage open sea tests have been finished in the waters near Wanshan Islands from November 2015 to June 2016. The device showed great power generation capacity with total generated output of 30530.57 kWh, and largest daily generation of 1847.09 kWh. During the open sea tests, the energy conversion efficiency was measured, and results show that capture width ratio of Wanshan remains higher than 20% in the wave period between 4 and 6.5 s and wave height range of 0.6–1.8 m. After operating in a wide range of conditions, including a tropical storm on May 27, amounts of tests data, experiences and lessons have been obtained and will be summed up and presented in the paper. [ABSTRACT FROM AUTHOR]