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421.
Various types of floating solar photovoltaic (FPV) devices have been previously proposed, designed and constructed with applications primarily limited to onshore water bodies or near-shore regions with benign environmental conditions. This paper proposes a novel FPV concept which can survive harsh environmental conditions with extreme wave heights above 10 m. This concept uses standardised lightweight semi-submersible floats made of circular materials as individual modules. The floating modules are soft connected with ropes to form an FPV array. We first present the conceptual design of the floats and the connection systems, including hydrostatic, hydrodynamic, and structural assessments of the floats. To verify the motion response performance, we carried out 1:60 scaled model tests for a 2 by 3 array under regular and irregular wave conditions. From the time series and response spectra, the motion characteristics of the array and the mooring responses are analysed in detail. The proposed concept exhibits excellent performances in terms of modular motions with limited wave overtopping and no contact is observed between adjacent modules under the extreme wave conditions. The findings of this study can serve as a valuable reference to developing reliable and cost-effective FPV technologies for offshore conditions. 相似文献
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This study investigates the hydroelastic analysis of a moored SFT (submerged floating tunnel) and the corresponding hydrodynamic pressure distribution under wave excitations. Time-domain discrete-module-beam (DMB) method, in which an elastic structure is modeled by multiple sub-bodies with beam elements, is employed to express the deformable tunnel with multiple mooring lines. Moreover, the top-down scheme is also adopted for detailed structure analyses with less computational cost, which applies the calculated hydrodynamic pressure distribution over SFT's surface to the three-dimensional finite element model. The hydrodynamic pressure includes both wave-induced diffraction pressure and motion-induced radiation pressure. For the validation of the developed numerical approach, comparisons are made with computationally intensive hydroelastic-structural direct-coupled method, two-dimensional wave flume experiment, and independently developed inhouse moored-SFT-simulation program. Furthermore, the influences of flexural motions with buoyancy-weight ratio (BWR) (or bending stiffness) and regular/irregular wave conditions on the dynamic pressure distribution and the resulting local stresses are investigated. 相似文献
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