Corrosion and biofouling impose serious hazards to the normal operation of marine propellers. The current research on the protection methods for marine propellers focuses on the propeller material itself, with insufficient attention to the propeller protective coating technology. This study introduces the anti-fouling principle of low surface energy fouling-release coatings and the development of relevant technologies, discusses the prospects and development directions of organosilicon-modified low surface energy anti-fouling coatings applied to marine propellers, and looks to the future development of anti-fouling coatings for marine propellers.

When a ship navigates through ice areas, structural and vibration responses will be generated on the ship hull under the collision of sea ices. The magnitude of the response is highly correlated with the factors such as sea ice conditions, ship speed, structural stiffness, and measurement position. To be distinguished from the localized structural vibration, the global motion and vibration response of the ship can be referred to as ship bumping, which has a large impact on the functionality of the shipboard equipment, easily resulting in various issues such as lessening of the fastenings. The ship bumping in ice has been examined based on the data measured by the distributed accelerometers on board the icebreaker Xuelong II during the voyage in the Antarctic ice area. The events of ship bumping in ice are identified by the neural network method based on the time-frequency analysis. The ship bumping signals are separated by the frequency spectral analysis to extract the key parameters of the ship bumping in ice, such as the acceleration amplitude, pulse width, and the occurring frequency. The identification and analysis methods are finally established. On this basis, the data of ship bumping in ice of various typical scenarios are analyzed to investigate the influence of sea-ice environment, ship speed, and measurement position on the key parameters of the ship bumping. The requirements of the capability of shipboard equipment to withstand bumping under different sea-ice conditions are then summarized to provide references for the selection of polar ship equipment.

Long-span structure is one of the typical structure features of ships. Low rigidity of the long-span structure causes large structure displacement and vibration amplitude, imposing difficulties in the vibration reduction design. The vibration of the long-span grillage structure is analyzed for a ship under bow thruster excitation in the current study. Topology optimization base structure is then established for the arrangement of the pillar under the long-span grillage structure. With the objective function of lightest structure weight based on SIMP method, the dynamic topology optimization design is carried out by using the stand pillar arrangement topology optimization model considering the vibration velocities of specified nodes as the constrain. The results show that a pillar arrangement plan with good vibration control performance is obtained by using the long-span pillar topology optimization method in the current study. This method can reduce the complexity of the design and the workload of the dynamic calculation, with a better vibration damping effect.

The topology optimization and shape parameter optimization technology are applied to the transverse webs in cargo hold. It enables not only the design of vertical girder without cross brace for the longitudinal bulkhead, but also the reduction of the structural weight of the cargo hold and the simplification of the construction process. The number and the length of the swash bulkhead can be minimized with the significant reduction of the envelope value of the static bending moment under all the operation conditions by the reasonable arrangement of the transverse bulkhead and the longitudinal bulkhead, which can improve the ship safety. It’s expected that the construction cost of the cargo hold of a very large crude carrier (VLCC) will be reduced by more than 5%.