Ocean currents are one of important resources of ocean energy. Although it is not widely harnessed at present, ocean current power has a vital potential for future electricity generation. In fact, several turbine syst...Ocean currents are one of important resources of ocean energy. Although it is not widely harnessed at present, ocean current power has a vital potential for future electricity generation. In fact, several turbine systems have been proposed in the world. In the present, we consider what factors should be considered in designing the system from the perspective of hydrodynamics. As an example, a floating Kuroshio turbine system which is under development in Taiwan is employed to serve as the case study. The system consists of five major parts; i.e. a foil float which can be employed to adjust the system submergence depth, a twin contrarotating turbine system for taking off the current energy, two nacelles housing power generators, a cross beam to connect two nacelle-and-turbine systems, and two vertical support to connect the foil float and the rest of the system.展开更多
In this paper, we present the study of system dynamics of the floating kuroshio turbine(FKT) system which is designed to harness ocean current energy. We focus on the mooring line system design and its interaction w...In this paper, we present the study of system dynamics of the floating kuroshio turbine(FKT) system which is designed to harness ocean current energy. We focus on the mooring line system design and its interaction with the FKT system. The effects of line diameter and two different auxiliary line systems were studied. Their responses in waves were also investigated. We integrated several commercial and in-house packages. The system buoyancy and weight and their centers were estimated using the Rhino software. The system hydrodynamic coefficients were obtained through WAMIT, system drag coefficient through FLUENT, turbine propulsive force through lifting surface code, and system dynamics through Orca Flex. The results show that the mooring line system can create strong influence on the FKT system operations in the ocean current environments.展开更多
Ocean current energy is a promising and reliable resource that offers sustainability and predictability in realizing green future needs.A diffuser-augmented horizontal-axis turbine is utilized to generate ocean curren...Ocean current energy is a promising and reliable resource that offers sustainability and predictability in realizing green future needs.A diffuser-augmented horizontal-axis turbine is utilized to generate ocean current energy.A numerical study on the impact of diffuser angle variations on the power coefficient has been carried out in the previous research.To elucidate the fluid dynamics aspects and further validation of previous computational results,the experimental investigation on the optimal design of tidal turbine with 20.04°diffuser augmentation is presented in this study.The study was conducted in a flowing tank with a current velocity of 0.7 m/s.The maximum power coefficient of 20.04°is 0.436 experimentally,which is a little smaller than the numerical value.Moreover,to reinforce the 20.04°result,a diffuser with an angle of 10.43°was also manufactured and tested experimentally.The maximum power coefficient of 10.43°is 0.303 experimentally,which is 3%smaller than the numerical value.It was concluded that the numerical approach might be considered satisfactory and represent similar phenomena to the experimental investigation in an application for modelling of multi-objective optimization.展开更多
基金supported by the support of Ministry of Science and Technology (Grant No. MOST 104-3113-F-019-002)
文摘Ocean currents are one of important resources of ocean energy. Although it is not widely harnessed at present, ocean current power has a vital potential for future electricity generation. In fact, several turbine systems have been proposed in the world. In the present, we consider what factors should be considered in designing the system from the perspective of hydrodynamics. As an example, a floating Kuroshio turbine system which is under development in Taiwan is employed to serve as the case study. The system consists of five major parts; i.e. a foil float which can be employed to adjust the system submergence depth, a twin contrarotating turbine system for taking off the current energy, two nacelles housing power generators, a cross beam to connect two nacelle-and-turbine systems, and two vertical support to connect the foil float and the rest of the system.
基金the grant from Ministry of Science and Technology, the Republic of China, under the contract MOST 105-3113-E-002019-CC2 and funding support from CSBC Corporation
文摘In this paper, we present the study of system dynamics of the floating kuroshio turbine(FKT) system which is designed to harness ocean current energy. We focus on the mooring line system design and its interaction with the FKT system. The effects of line diameter and two different auxiliary line systems were studied. Their responses in waves were also investigated. We integrated several commercial and in-house packages. The system buoyancy and weight and their centers were estimated using the Rhino software. The system hydrodynamic coefficients were obtained through WAMIT, system drag coefficient through FLUENT, turbine propulsive force through lifting surface code, and system dynamics through Orca Flex. The results show that the mooring line system can create strong influence on the FKT system operations in the ocean current environments.
基金This research was funded by Kementerian Riset dan Teknologi/Badan Riset dan Inovasi Nasional(Kemenristek/BRIN)through Publikasi Dasar Unggul Perguruan Tinggi(PDUPT)grant program,grant number NKB-197/UN2.RST/HKP.05.00/2021.
文摘Ocean current energy is a promising and reliable resource that offers sustainability and predictability in realizing green future needs.A diffuser-augmented horizontal-axis turbine is utilized to generate ocean current energy.A numerical study on the impact of diffuser angle variations on the power coefficient has been carried out in the previous research.To elucidate the fluid dynamics aspects and further validation of previous computational results,the experimental investigation on the optimal design of tidal turbine with 20.04°diffuser augmentation is presented in this study.The study was conducted in a flowing tank with a current velocity of 0.7 m/s.The maximum power coefficient of 20.04°is 0.436 experimentally,which is a little smaller than the numerical value.Moreover,to reinforce the 20.04°result,a diffuser with an angle of 10.43°was also manufactured and tested experimentally.The maximum power coefficient of 10.43°is 0.303 experimentally,which is 3%smaller than the numerical value.It was concluded that the numerical approach might be considered satisfactory and represent similar phenomena to the experimental investigation in an application for modelling of multi-objective optimization.