Clear, reliable and communicative icons, central to navigation in ship-bridges, rely on the International Electrotechnical Commission (IEC) 62288 guidelines. This contrasts with uses of technical, industry icon guidance standards and prototypical icon alternatives in Interaction Design. This article explores how guidance on standardised navigation icons for common function controls in IEC 62288 may limit icon development. Following review of related research and analysis of existing professional icon guidelines, conceptual icon design prototypes from Interaction Design are presented to offer prospective and communicatively centred contributions to icon standards. The study is located within qualitative, situated inquiry and Research through Design methodologies in Human-Computer Interaction encompassing conceptual design prototyping and visual design methods. Comparative analysis is made of established icon standard forms and proposed alternatives from the maritime interaction design OpenBridge project. Key findings include identifying that current guidance frameworks for navigational icons contain semantic gaps for interaction designing and operational usage; applicability of a proposed framework enhancing communicativity in icon design and standardisation; and qualitative contribution of a prototype Icon Library to navigation icon designing. Implications for navigation icon design and standardisation processes via conceptual prototype design are discussed as in need of further user study and uptake in the sector.
Decarbonization of the maritime industry requires fostering habits and conditions that enable operators to make energy-conscious decisions. User interface (UI) design can play a key role in developing strategies to enhance user awareness and motivation. Specifically, UI design can implement feedback mechanisms that help users better understand the consequences of their actions on energy consumption. This approach has demonstrated measurable reductions in energy use in domains such as automotive systems and home appliances. However, research on eco-feedback and its implementation through UI design remains limited in the maritime context. We aimed to address this gap by conducting a systematic review of eco-feedback research and developing an eco-feedback framework (EFF) for UI design. We identified 39 strategies for providing feedback on a UI. These strategies were organized and synthesized into a design framework, the EFF. We illustrate the proof of concept of the EFF with a maritime example: a cruise control system that regulates a ship's speed and power use. Finally, we discuss other potential applications of the EFF in UI design research and conclude by highlighting its importance in fostering habits and conditions for energy-conscious decision-making in the maritime industry.
An increase in customer demand for cruising is prompting major industry players to allocate considerable resources to the construction of new ships that are energy efficient and environmentally compliant. This study examines the energy transition possibilities by retrofitting a large cruise ship and develops a procedure to evaluate the suitability of liquid hydrogen as a potential decarbonization solution. The utilized approach in this paper includes technical and safety assessment of the possible energy system options with liquid hydrogen as fuel, to identify the optimal solution. The technical assessment evaluates the required volume and weight of each system option using vessel particulars and operational data. The energy system sizing is based on available technology data in the market, and the sizing of fuel storage system is based on a sample liquid hydrogen containment system and its adaptability onboard. Additionally, a safety assessment of hydrogen storage and each energy system option is conducted, analysing the applicability onboard, with a focus on the frequency of hazardous events. This approach can be transferred to other ship types and further developed to compare other alternative fuels. Furthermore, it can be improved by incorporating economic and regulatory assessments. The results of a sample case study with installed 40 MW power onboard, indicate that decarbonization of cruise ships using liquid hydrogen is possible. Among studied scenarios, a system with 40 MW PEMFCs and 10 MW batteries is suggested as an optimum solution. This system, despite requiring 1.87 more volume, represents only 35% of conventional system weight. Within the ship body three large liquid hydrogen tanks are installed to provide 4926 m3 fuel. Consequently, bunkering stops are required on a weekly basis.
This paper presents a design space exploration (DSE) for the development of an innovative special-purpose installation vessel for tension leg platform (TLP) floating offshore wind turbines. The concept, named "Windchanger," features an installation deck integrated with the stern design to facilitate turbine lowering and recovery. The DSE model conducts a tradeoff analysis using a parametric model of the hull and installation deck, evaluating both technical feasibility and cost-effectiveness. The model evaluates various scenarios across two demonstration operational areas: the North Sea and the U.S. East Coast. Results evaluated the principle design limitation across various TLP designs, ship concepts, installation design concepts, and operational scenarios. Findings indicate that the transport capacity measured in the number of TLPs, from 1 to 5, has a significant influence on design considerations and economic effectiveness. The overall results show that the Windchanger concept has the potential to be a competitive installation solution.
This article deals with the outline and comparison of design approaches and verification criteria for the analysis of a typical structural layout of a helicopter deck intended for mega yachts. Starting from an introductory analysis on the various helicopter types on the market, on the different landing methodologies and on the current regulations of classification societies, the rule scantling requirements of the structural layout are outlined. Subsequently, rule-based assessment approaches are compared with different direct analysis methods, ranging from simplified analytical formulations of structural mechanics to advanced numerical techniques, properly considering non-linearities and dynamic behaviour of the examined problem within the simulations. Finally, the results obtained are critically compared in order to offer the designer both the merits and drawbacks of each scantling assessment approach to a rather unconventional application, that is, the helicopter deck of a mega yacht, from an everyday working practice perspective. It turns out that the structural scantling design of a helicopter deck does not always require advanced and time-consuming numerical approaches. Rather, they should be applied when specific and detailed information about structural behaviour is needed.
The main parameter employed in descriptions of cavitating flows is cavitation number. This number should be calculated using the actual pressure within the cavity. However, the pressure in the cavity was not determined in many known experiments and the employed values of cavitation numbers were calculated using the vapor pressure instead of the actual cavity pressure there. This complicates interpretation of the experimental data and validation of computational tools. Meanwhile, as shown experimentally many decades ago, the pressure in cavities substantially depends on the inflow air content. A correction to the vapor cavitation number considering the impact of inflow air content and tuned to the experimental data from a single water tunnel is described in this article. This correction is validated with the various well-known experimental data. Such a correction makes it possible to revise the old experimental data and, as a result, to improve the agreement of the results of diverse computations with the corresponding measurements.
This paper investigates the carbon intensity of “average” ships, i.e., the ships of different types and sizes which, in 2018, performed an average transport work and emitted an average amount of CO 2 , according to the data published in the Fourth IMO GHG Study. The goal of the study is to identify the ship types and sizes which may be regarded as the best and the worst performing with respect to carbon intensity. Using the data available from the Fourth IMO GHG Study, the Carbon Intensity Indicator (CII) is calculated for each of the examined average ships and the obtained values are compared to the CII reference lines valid for 2023, 2024, 2025, and 2026. Based on the calculations, carbon intensity ratings may be assigned to examined ships for four consecutive years. Thus, it is possible to estimate the evolution of carbon intensity of examined fleet segments, provided that no measures for improvement of carbon intensity would be implemented in years to come. The analysis has shown that most of the current merchant fleet would exhibit an “inferior” (label E) performance with respect to the carbon intensity. While some of the examined average ships with “inferior” rating could attain the “moderate” rating (label C) in 2023 by relatively small reductions of 2018 CII values, most of the other ships would require considerably greater improvements. Identification of the “worst performers” would indicate which ships require immediate attention with respect to the carbon intensity. Thus, the outcomes of the study may serve as an input to policy makers when deciding on measures addressing the carbon intensity of maritime shipping.
Foiling sailing yachts achieve high forward velocities. When sailing in high waves, crashes of the hull on the free surface can occur, leading to rapid deceleration and risk of injury to the crew. This article discusses the implementation of a dynamic velocity prediction program (DVPP) for an IMOCA 60 in order to predict when crashes occur. Simulating foiling in strong winds and high waves required extending the DVPP compared to the existing literature with a nonlinear representation of wave loads, a more realistic representation of the forces on the sail, and three-dimensional effects in the forces on the foil. After comparing the simulated response in waves to results from the literature, the DVPP of the IMOCA 60 was used to predict a crash. Analysis of the encountered crash events showed that they occurred as a result of an unfavorable phase relation between the vertical position of the yacht and the free surface elevation in following waves.
Ventilated cavitation can enhance the performances of various vehicles, including hydrofoil ships. Partial cavitation can reduce the drag coefficients of hydrofoils. For natural partial cavitation of specially designed hydrofoils this reduction is coupled with a significant increase of their lift. The intention to obtain a similar enhancement at smaller vehicle speeds using ventilation of hydrofoil by air looks natural. However, for hydrofoil ventilated cavitation the lift increase at the same cavitation numbers is substantially smaller. The physics of this lift difference is explained here via numerical analysis of the data obtained in water tunnel during experiments with the specially designed hydrofoil OK2003. The unavoidable lift difference is caused by a decrease of medium density downstream of the ventilated cavity due to the air escape from it.
BACKGROUND: Merchant ships, despite huge technological progress, are still operated by qualified navigators. According to ergonomics principles, human is a part of the whole system and is affected by the surrounding environment. OBJECTIVE: The purpose of the paper was to assess the ergonomic awareness of professional navigators, to understand their expectations towards navigation bridges and to check if they obtain enough support from their workplace. METHODS: A special questionnaire was developed and 200 responses were obtained from seafarers with license of Officer Of theWatch or higher. Statistical analysis were carried out to find out relationships and differences between answers and groups of respondents. RESULTS: Improper ergonomics and less than optimal working conditions were not isolated incidents and occurred to be rather common problem of the industry. The results suggest that ergonomic awareness is at relatively high level, however this knowledge is frequently not used in practice. CONCLUSIONS: Poor design and lack of proper ergonomics training might contribute to commonly experienced signs of fatigue, pain episodes and therefore reduced performance of seafarers. Navigators find ergonomics important, however navigation bridges often do not meet ergonomics and comfort standards, therefore there is still a room for improvement in this area.
In the fiercely competitive shipbuilding industry, precise cost estimates must be considered as they serve as a critical input for determining market prices effectively and ensuring a small profit for the shipyard. In Western Europe, where most projects are Engineering-To-Order (ETO), cost estimations are extra challenging, due to lack of similarity between projects. On top of this, cost estimations are becoming increasingly difficult in a market confronted by mounting challenges related to safety regulations, costeffectiveness, and the pressing need to address energy conservation and environmental protection. New technologies introduce changes in nearly all aspects of shipbuilding design and construction. This article conducts a literature review, to present the state-of-the-art methods for estimating man-hours, explicitly focusing on man-hours for shipyard production, excluding overhead costs and challenges the suitability of existing systems for ETO and especially for the changes caused to ships by the energy transition. An indication is given of the practicality of each method as outlined in the literature. A solution direction, incorporating the construction process, is proposed to improve cost estimations for ETO projects in pre-contract phase.
This paper presents the mathematical model used in MARIN’s time domain software to describe the hydrodynamic loads excited by a rudder. The paper provides a detailed description of the mathematical model and its theory, along with highlighting the novel features that have been added to extend the model to four quadrants operations. Furthermore, the paper compares the mathematical model with experiments, showcasing the model’s capabilities and shortcomings. For this comparison, a spade rudder behind the KRISO Container Ship with and without a propeller upstream has been used as a case study to illustrate how the model performs in practice.
In head waves, water jet impacts due to run up can occur as a result of the structural configuration of some floating structures, reducing workability. Wave attenuation near the floater may reduce the risk of water jet impacts. This paper presents a numerical study of the performance and attenuation mechanisms of various plate type fixed free surface breakwaters and their ability to prevent water jet impacts on adjacent structures. Simulations are performed in two dimensions with a numerical method based on the Navier–Stokes equations in the presence of a free surface. The breakwater models are evaluated in two irregular sea states in terms of wave transmission, reflection and energy dissipation and by their ability to reduce water jets impacts on adjacent structures. A 60 degree inclined plate is found to induce a large wave energy reduction, little wave transmission and reflection and to experience little wave loading while effectively reducing water jet impacts.
Surrogate modelling techniques such as Kriging are a popular means for cheaply emulating the response of expensive Computational Fluid Dynamics (CFD) simulations. These surrogate models are often used for exploring a parameterised design space and identifying optimal designs. Multi-fidelity Kriging extends the methodology to incorporate data of variable accuracy and costs to create a more effective surrogate. This work recognises that the grid convergence property of CFD solvers is currently an unused source of information and presents a novel method that, by leveraging the data structure implied by grid convergence, could further improve the performance of the surrogate model and the corresponding optimisation process. Grid convergence states that the simulation solution converges to the true simulation solution as the numerical grid is refined. The proposed method is tested with realistic multi-fidelity data acquired with CFD simulations. The performance of the surrogate model is comparable to an existing method, and likely more robust. More research is needed to explore the full potential of the proposed method. Code has been made available online at https://github.com/robertwenink/MFK-Extrapolation.
This paper explores the design and feasibility of a 200-passenger, 30- to 40-knot emission-free ferry as a potential variant of the traditionally powered Coastal Cruiser 200 ferry currently operating in the Chinese Pearl River Delta. The Pearl River Delta is one of China’s most densely urbanized regions and faces numerous social, health, and economic issues due to air pollution. In addition, globally, there are no currently-operating zero-emission ferries that, at minimum, sail at 30 knots and carry 200 passengers. To assess the feasibility of the new ferry, a two step approach was followed. First, an evaluation of efficiency improving measures, energy carriers, and propulsion systems was performed to assess the tradeoffs and identify early design choices. Second, to quantify the most technically feasible design, a technical parametric model was developed specifically for this case study. Results showed that the ferry is technically feasible using batteries, compressed hydrogen fuel cells, or liquid hydrogen fuel cells; however, each has its distinct advantages and disadvantages which influence the potential final viability. Despite the regional focus of the case study, results are applicable to all ferries with similar design requirements.
This article examines the potential implications of using iron powder as an alternative fuel on the design and performance of container ships. Iron powder is a relatively new alternative energy carrier and one in which little research has been done into the application on-board vessels as part of the maritime energy transition. The key benefits of iron powder are that it is a circular energy carrier and the combustion process emits no greenhouse gases. Transitioning to iron powder is expected to have far reaching implications for the design and performance of ships. Thus, this paper aims to perform the first study assessing the potential of this concept applied to container ships. To do so, a preliminary design space was explored with a custom parametric design model developed to generate preliminary designs of iron fuelled container ships as a function of the operational profile. Using this parametric design model, it was identified that iron fuelled container ships are weight limited, unlike conventionally fuelled container vessels. Furthermore, iron fuelled container ships are best suited for short voyages at low cruising speed. For these voyages, it was concluded that iron fuelled ships are economically feasible; however, other alternative marine fuels are likely more profitable than iron due to the low efficiency of iron fuelled ships and the high cost of iron per unit energy.
