In this study, the heave plate of a DeepCwind floating wind turbine platform with a capacity of 5 MW was used as the research object. The influence of the perforated chamfer on the hydrodynamic performance of the heave plate was studied through physical experiments and numerical simulations. Vertical force amplitudes, additional mass coefficients, and damping coefficients were obtained for heave plates with different types of perforations. The results of the numerical simulations and physical experiments revealed that hydrodynamic coefficients changed consistently. During the same period, the damping and additional mass coefficients of the heave plate gradually decreased and increased with an increase in the motion amplitude, respectively. When comparing with different perforation angles, the coefficients initially decrease and then increase with an increase in the perforation angle. In the case of a large perforation angle, the coefficients were higher than those of the conventional heave plate without perforations.

The increasing use of automation in fishing vessels has improved trawling efficiency while directly affecting the fishing capacity and cost of fishing vessels. Among the various influencing factors, warp tension and warp length can be varied to automatically balance the retraction and release of warp control. We combined the two parameters and independently designed and developed the key equipment for fishing vessels—the warp dynamometer and meter counter—and control software. The accuracy of the warp tension and length measurements was improved. The designed equipment was applied to sea trials under different working conditions, and the test data records were exported. Next, filtered time-domain graphs of the required parameters were plotted through complex Fourier transform, first-order low-pass filtering, and inverse Fourier transform. The results of data processing using various parameters were compared and analysed to determine the variation trends of the parameters and verify the effects of their balance control. The results indicated that using an automatic balance control system that combines warp tension and warp length can be effective for the fishing operation of offshore double-deck trawlers. In addition, first-order low-pass filtering can be used to filter complex warp tension data. This study also determined the relationship between warp tension and experimental parameters such as warp length and ship speed during the release of control. After the balance control of warp tension and warp length, the net mouth area increased by 30.7% and 36.5%, respectively, and the fishing efficiency of the vessel improved considerably.

In this paper, we use the finite element software MSCPATRAN and MSCNASTRAN to establish the FEM model. Then we analyze the racking condition strength under the conditions of inclined shipping, and discuss the stress of the hull structure, the distribution of the hot spot and the deformation of the deflection under the flexible design concept. Some general conclusions under the design concept are obtained, which will be expected to contribute to the development of the design concept of the whole ship flexible structure.

The DeepCwind floating wind turbine platform has become one of the most successful structures for accommercial floating wind farms, and the stability of it is crucial for survivability. Hence, this paper studies an anti-oscillation device with the purpose of reducing the heave and surge effects of the platform. The influence of various chamfered perforations at different sizes of the anti-heave device on the floating platform was further studied by numerical and experimental methods. Furthermore, through an analysis of the surge and heave of the pedestal with anti-heave devices with different chamfered perforations under different wave heights and wave periods, the effects on the hydrodynamic performance of the pedestal were studied. Physical experiments were conducted on a pedestal with anti-heave devices with chamfered perforations under the working conditions of different wave heights and wave periods to verify the reliability of the numerical simulation. The results show that the anti-heave effect of the anti-oscillation device is obvious under the small wave period and large wave height. Under the working conditions of different wave heights and wave periods, different perforated chamfers have different effects on reducing the oscillation of the pedestal, and its effect does not change linearly with an increasing chamfer. Under most working conditions, the anti-heave effect of the 35° chamfered perforated model was found to be the most obvious.

Among renewable energy sources derived from the ocean, wind power has developed rapidly. This article proposes an optimization algorithm framework that integrates two objectives: aerodynamic shape optimization and structural optimization. For practical reasons, the 5−MW wind turbine blade was selected as the research object, and the sea conditions near the East China Sea were chosen as the environmental parameters for its service environment. The FAST simulation software was employed for verification purposes. The results indicated that the optimized blade not only meets the target power output but also possesses unique economic advantages, such as being lightweight and exhibiting low aerodynamic force.

Due to the limited availability of land resources, offshore wind turbines have become a crucial technology for the development of deep-water renewable energy. The multi-floating body platform, characterized by its shallow draft and main body located near the sea surface, is prone to significant motion in marine environments. The proper chamfering of the heave plate can effectively enhance its resistance during wave action, thereby improving the stability of the floating platform. The optimal chamfer angle is 35°. Considering the complexity of the floating body’s motion response, this study focuses on the damping characteristics of the heave plate with 35° chamfered perforations. Using the NREL 5 MW three-column semi-submersible floating wind turbine platform as the research model, the hydrodynamic characteristics of the floating body with a perforated heave plate are systematically studied through theoretical analysis, numerical simulation, and physical tests. The amplitude of vertical force under various working conditions is measured. Through theoretical analysis, the additional mass coefficient and additional damping coefficient for different working conditions and models are determined. The study confirms that the heave plate with 35° chamfered perforations significantly reduces heave in the multi-floating body.