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International Maritime Organization (IMO) provided manoeuvrability standards for all ships above 100 m to ensure the ship's safety and surroundings. In the preliminary design stage, one way to ensure a ship's manoeuvrability under IMO standards is to use empirical methods that are cheaper and less time-consuming than model tests. Empirical methods used analysis regression to develop their formula from the model test result database, and their formula depends on ship hull parameters and dimension ratios such as , , , and . However, the database of the existing empirical formulas is limited to small-medium merchant ships and fishing vessels, as consequences for larger ships are inaccurate and have a significant error in predicting ship manoeuvres. This study modified the existing empirical formulas by adding specified ship data into the existing database and analyzing the accuracy of predicting ship manoeuvres using the Maneuvering Modelling Group (MMG) model. We verify by adding the selected ship data into the existing database, which shows improvement in predicting ship manoeuvres. The modified formulas show improvement by only giving 5% RMSE of tactical diameter and 3% RMSE of ship advance in turning manoeuvre, and this is a 78% overall improvement in predicting the turning motion of ultra-large container ships compared to previous formulas. The quantitative and qualitative produce better estimation result that indicates the right track to derive the empirical formulas for Ultra-Large Container ships.

As the size of ships increases, the size and output power of their thrusters also increase. When a large ship berths or unberths, the jet flow produced from its thruster has an adverse effect on the stability of quay walls. In this study, we conducted a numerical analysis to examine the impact of the thruster jet flow of a 30,000 TEU container ship, which is expected to be built in the near future, on the stability of a quay wall. In the numerical simulation, we used the fluid–structure interaction analysis technique of LS-DYNA, which is calculated by the overlapping capability using an arbitrary Lagrangian Eulerian formulation and Euler–Lagrange coupling algorithm with an explicit finite element method. As the ship approached the quay wall and the vertical position of the thruster approached the mound of the quay wall, the jet flow directly affected the foot-protection blocks and armor stones. The movement and separation of the foot-protection blocks and armor stones were confirmed in the area affected directly by the thruster jet flow of the container ship. Therefore, the thruster jet flows of ultra-large ships must be considered when planning and designing ports. In addition, the stability of existing port structures must be evaluated.

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The research addresses the problem of an ultra-large container ship mathematical model adjustment based on sea trials. In order to verify the model’s adequacy, simulated data had to be compared to the trial report data, which was obtained in ballast condition with significant trim. In such circumstances, model coefficients cannot be calculated by known methods and have to be corrected as per trial data. It is proposed to determine translational motion coefficients first. To get optimal results, it was also proposed to divide the objective function into kinematic and dynamic components, with each component being assigned a weighting factor. A separate objective function component was assigned to the zig-zag maneuver, which includes the first and second overshoot angles.

Decarbonising the naval shipping sector is of paramount importance to decrease global CO 2 emissions. This work presents a techno-economic analysis of onboard solvent-based carbon capture for an ultra-large container ship, powered by two dual-fuel engines fed with either heavy fuel oil or liquefied natural gas. Different case studies are proposed depending on the fuel used by the ship and on the chosen design to supply the necessary heat and electricity to the carbon capture unit. Aside a conventional strategy based on heat provided via fuel combustion in a boiler, a novel configuration based on electric heat pump is investigated. The economic analysis is based on a real inter-continental journey. The results highlight that onboard carbon capture determines an increase in fuel consumption with respect to the unabated ship, that varies depending on the exhaust gas CO 2 content (hence, on the ship fuel) and on the selected process design. The integration of the electric heat pump leads to a significant decrease in this additional fuel consumption and better results in terms of CO 2 avoidance and costs. The carbon abatement cost is found in the range of 64–149 €/t of CO 2 avoided. • CO 2 capture onboard an ultra-large container ship is investigated. • A novel configuration based on electric heat pump for reboiler duty is proposed. • Electrified heat leads to better results compared to fuel steam boilers. • The cost of CO 2 avoidance is found between 64–149 €/t of CO 2. • Onboard CO 2 capture is cost-competitive for about 100 €/t carbon tax. [ABSTRACT FROM AUTHOR]

This work proposed a novel hybrid cooling system that applies the mist-spraying technology to improve the thermal conditions and loading capacity of refrigerated containers (reefers) in the cargo holds of ultra-large container ships. Thorough studies were carried out via both experiments and simulations. First, effects of the air supply rate and the mist spray rate on the reefer's exhaust temperature and the ambient temperature of the reefer Lab. were investigated in comparison with the simulation models. Then the possible operating conditions of the air and mist flow rates were clarified and the cargo hold from a practical container ship was adopted as the example to verify their feasibility. Finally, the possible capacity improvement for loading reefers was discussed while the method of determining the operating range of mist spray rates and air supply rates was also established. It was found that great benefits were generated by the proposed system in lowering the reefer's exhaust temperature and improving the thermal conditions inside the cargo hold. In addition, a substantial capacity improvement for loading reefers in the cargo hold was also achieved in the present study. The study will help in enhancing the efficiency and economic benefits for the reefer transportation. [ABSTRACT FROM AUTHOR]

With the increase in the size of containerships, the lowest wet natural frequencies can be as low as 0.5 rad/s for vessels whose lengths are beyond 300 m. These lower frequencies make the estimation of wave loads when considering the hull flexibility quite challenging. Because no numerical tools are able to account for all of the nonlinear effects properly and there is not enough experimental data available for validation, the extent that current numerical tools can correctly predict the hydroelastic effects is a concern. This paper adopts a nonlinear hydroelastic code, WINSIR, to calculate the nonlinear hydroelastic response of an 8600-TEU containership model advancing in regular waves. The calculated results are compared with test data in terms of the first, second, third, fourth and fifth harmonics of the vertical bending moment amidships. Finally, the uncertainties in the experiments are discussed, and conclusions are given at the end of this paper. [ABSTRACT FROM PUBLISHER]

Accurate estimation of the wave-induced extreme hogging vertical bending moment (VBM) is of vital importance for the design of container ships because container ships are normally under hogging conditions in still water. According to the empirical formulas proposed by the classification society rules, the design hogging VBM can be approximately 20 % smaller than the design sagging VBM for vessels with small block coefficients. High-order harmonic components in the vertical load effects, which are induced by the nonlinearities in the hydrodynamic forces and ship hull geometry, contribute to the asymmetry. Previous studies have shown that the nonlinear hydrostatic and Froude-Krylov forces increase the sagging VBM significantly. Current numerical tools are able to reveal this asymmetry to a certain extent. There is, however, little focus on the nonlinear pressure under the bow bottom, which is a more likely contributor to the hogging VBM. Several unexpected phenomena have been observed for large container ships. The wave-frequency sagging and hogging VBMs followed each other closely, and hence did not reflect the significant nonlinear factors as expected. In this paper, the test data of two (8600-TEU and 13000-TEU) ultra-large containership models in both regular and irregular head waves are systematically studied. In regular waves, the influence of the second and third harmonics on the fundamental hogging peaks and sagging troughs is estimated by comparing both the amplitude and phase difference relative to the first harmonic peaks. In irregular waves, the focus is on the statistical characteristics of the wave-induced nonlinear vertical load effects. To achieve a balance between results in regular and irregular waves, the influence of the second harmonics is evaluated through bispectral analysis. [ABSTRACT FROM AUTHOR]