The global transition towards more sustainable energy systems is placing increasing pressure on the maritime industry to reduce its greenhouse gas emissions. In response, the International Maritime Organization (IMO) has set the ambition of reaching net zero greenhouse gas emissions by/or around 2050. Achieving this objective requires the development and adoption of alternative propulsion technologies capable of supporting the energy demands of commercial shipping. Nuclear propulsion represents an attractive candidate, particularly for long distance shipping, because it can provide continuous high density energy, long operational endurance, and very low operational greenhouse gas emissions during onboard operation. However, its application introduces safety and integration challenges.

Existing maritime, nuclear, and classification requirements provide relevant safety principles, but they remain fragmented and do not provide a single modern methodology for assessing nuclear and maritime hazards together and translating the resulting findings into ship design decisions. To address this
problem, the work was divided into two distinct phases.

The first phase established the technical, regulatory, and methodological basis of the study through a literature review. It examined the fundamentals of marine nuclear propulsion, the shipboard systems required to support nuclear safety, relevant safety frameworks and representative accident scenarios, and available risk assessment methods. From this review, Hazard Identification Study (HAZID) and Bowtie analysis were selected within a Formal Safety Assessment (FSA)-informed structure, supported by Defence-in-Depth (DiD) and an As Low As Reasonably Practicable (ALARP) approach.

The second phase applied this methodology to a reference nuclear powered bulk carrier. A HAZID identified and ranked 95 scenarios across five functional nodes, after which three representative top events were examined in greater detail using Bow-tie analysis. The assessment identified weaknesses related to barrier dependencies, system segregation, release management, electrical support, heat
rejection, and severe condition mitigation. These findings were translated into six concept level design recommendations and implemented in a second design iteration.

Twenty scenarios affected by the recommendations were reassessed. Following the second design iteration, no High- or Extreme-risk scenarios remained within this subset, while the number of Mediumrisk scenarios decreased and the number of Low-risk scenarios increased. The study concludes that the methodology proposed in this research provides a structured and traceable framework for linking hazard identification, barrier assessment, design improvement, and reassessment. A key finding is that the nuclear installation and the vessel should be developed as one integrated safety system rather than as separate design domains. ... Read more

The increasing complexity of offshore vessels requires improved methods to evaluate system architectures during early-stage design. Current design approaches often assess subsystems separately, limiting the ability to explore system-level trade-offs between cost, reliability, and operational performance. This paper presents an MBSE-based decision support framework for the automated generation and evaluation of offshore vessel system architectures. The proposed approach integrates a Capella-based system model with automated architecture extraction, configuration generation, and multi-criteria evaluation. Alternative architectures are assessed by combining cost modelling with reliability-based risk analysis. The framework is demonstrated through an offshore vessel cooling system case study, where multiple configurations are generated and compared. The results show that the framework can identify cost-risk trade-offs between different levels of redundancy and system integration, supporting the selection of balanced architectures. The proposed methodology extends the application of MBSE from system modelling towards quantitative architecture exploration, providing designers with a structured approach for more informed decision-making during concept design. ... Read more

The maritime industry faces increasing pressure to reduce greenhouse gas emissions in response to international climate targets and increasingly stringent environmental regulations. This challenge is particularly relevant for the cruise industry operating in Northern Europe, where emission control areas and national regulations demand a transition towards low- and zero-emission operations. Although various alternative energy carriers have been proposed, limited research has systematically evaluated their applicability to cruise ships operating under the unique operational and regulatory conditions of Northern Europe.
The objective of this research is to determine the technical, economic, and regulatory feasibility of alternative energy carriers for new-build cruise ships operating in Northern Europe. A comparative assessment framework was developed that combines ship particulars, representative operational profiles, and energy carrier characteristics to evaluate alternative propulsion concepts. The model iteratively determines the required vessel modifications to accommodate different energy carriers and subsequently evaluates the resulting capital expenditure, operational expenditure, emissions, and regulatory compliance. Four representative cruise ship sizes, seven operational profiles, and five alternative energy
carrier–converter configurations were evaluated. The developed methodology was verified and validated using the Validation Square proposed by Pedersen.
The results show that hydrogen represents the most robust alternative energy carrier, remaining technically feasible for all evaluated ship sizes and operational profiles while also satisfying current and anticipated emission regulations. Batteries provide a viable zero-emission solution for shorter operational profiles but remain constrained by their low energy density, requiring significant increases in vessel dimensions for longer routes. Methanol proves technically feasible but is currently limited by high projected operational costs and its inability to fully comply with the strictest emission regulations in Northern Europe. Sensitivity analyses demonstrate that the conclusions remain robust under variations in the principal model assumptions and operational profiles.
This research contributes an integrated methodology for evaluating alternative energy carrier pathways during the early design stages of cruise ships. Rather than producing a detailed vessel design, the developed framework supports decision-making by systematically comparing technical, economic, and regulatory feasibility. The methodology provides a foundation for future studies and can be adapted to evaluate emerging energy carriers, new operational scenarios, and future developments in maritime regulations. ... Read more

Cable laying vessels are capital-intensive, long-lived assets whose required capabilities depend on uncertain future offshore wind developments. This thesis investigates how deep uncertainty can be addressed during the early-stage design of a cable laying vessel, focusing on mission-equipment choices such as cable-storage capacity, carousel arrangement, lay-line configuration, and tensioner capacity.

Dynamic Adaptive Policy Pathways is adapted as a design-support framework and combined with a parametric vessel-evaluation model. A library of 11,304 mission-equipment configurations is evaluated against synthetic offshore wind export-cable project portfolios. The scenarios explore increasingly demanding conditions related to cable length, distance from shore, high-voltage direct-current systems, water depth, and floating offshore wind. Performance is assessed using technical feasibility, campaign requirements, fuel consumption, equipment utilisation, and mission-equipment capital expenditure.

The results show that no single configuration performs best under all future conditions. Greater cable-storage capacity improves performance for longer and more remote projects, while higher tension capacity becomes increasingly important in deeper water. Two-line capability is particularly valuable for high-voltage direct-current projects. These insights are translated into adaptive design pathways that identify potential upgrades as future requirements develop. The resulting framework supports transparent comparison of under-specification, over-specification, and adaptability trade-offs before major design decisions are locked in. ... Read more

The superyacht sector is under increasing pressure to reduce operational emissions and improve onboard energy efficiency. One relevant opportunity is the better use of thermal energy, since yachts require heating and cooling under varying operating conditions while propulsion and power-generation systems can provide recoverable waste heat. Evaluating the effectiveness of a Thermal Energy Management System (TEMS) during the design stage is therefore challenging, because both thermal demand and heat availability depend on operational profile, climate zone, occupancy level, and system configuration.

This thesis develops a method to evaluate yacht TEMS designs across multiple operational scenarios. The method combines Multi-Criteria Decision Analysis (MCDA), adapted Scenario-Based Reasoning (SBR), and analytical calculations. MCDA provides the overall comparison structure, SBR is used to evaluate performance-based Key Performance Indicators (KPIs) across representative scenarios, and analytical calculations are used for design-dependent KPIs. The selected KPIs are Load Coverage, Coverage Durability, Usage Ratio, Combined Heat, Power, and Cooling (CHPC) Efficiency, Volume Ratio, Mass Ratio, and Cost Ratio.

The method is applied to M/Y Obsidian, an 84.2 m Feadship yacht used as reference case. The scenario matrix combines seven climate zones, three operational profiles, three occupancy levels, and four representative weather-parameter cases, resulting in 252 evaluated scenarios. For each scenario, the weather conditions, thermal demand, useful heat and cooling generation, and performance-based KPIs are calculated. The design-dependent KPIs are then determined from the installed volume, mass, and estimated cost of the TEMS components.

Two configurations are evaluated. Design 1 represents the baseline TEMS, based on engine heat recovery, an electrically driven chiller-heat-pump branch, an electric heater, and thermal storage. Design 2 is introduced as a first improvement iteration, in which the electrically driven chiller is downsized and an absorption chiller is added to use engine high-temperature heat for cooling production during anchor and sailing conditions.

The results show that both designs cover the required thermal demand in all evaluated scenarios. In Design 1, the most critical cases occur in high-occupancy Mediterranean scenarios, where the recovery heat exchanger, electric heater, and heat tank become highly loaded. The analysis also shows that a large share of the available engine high-temperature heat remains unused, indicating that the main limitation is not the availability of recoverable heat, but the capacity and configuration of the recovery path.

Design 2 improves the use of recoverable engine heat in anchor and sailing conditions and leads to a small increase in CHPC Efficiency in warm representative scenarios. However, the improvement is profile-dependent and does not affect harbour operation, where no engine heat is assumed to be available. In addition, the absorption chiller increases the installed volume, mass, and cost of the system.

The final ranking combines CHPC Efficiency, Volume Ratio, Mass Ratio, and Cost Ratio using equal weighting factors and ratio-to-best normalization. Under these assumptions, Design 1 is ranked first in all weather-parameter cases. Design 2 therefore shows a technically relevant improvement, but the efficiency gain is not sufficient to compensate for its larger spatial, mass, and economic impact. ... Read more

The global maritime sector faces increasing pressure to reduce greenhouse gas emissions, comply with emerging regulatory frameworks, and transition toward more resource-efficient fleet renewal strategies. While vessel refits are frequently promoted as circular alternatives to newbuild vessels, decision-makers lack systematic tools to evaluate the strategic, environmental, and economic impacts of different refit pathways. Existing circular economy assessment frameworks are either too generic, developed for land-based industries, or primarily focused on newbuild vessels. This thesis addresses this gap by developing a structured, KPI-based methodology that supports early-stage decision-making for vessel refits, enabling transparent comparison between repair, refurbish, remanufacture, and newbuild alternatives.

A Design Science Research approach is applied to derive a two-step framework. The first step identifies feasible circular strategies based on vessel and component characteristics, regulatory requirements, and intervention depth. The second step evaluates each strategy using 32 Key Performance Indicators (KPIs), synthesised from an initial database of 87 indicators derived from literature, regulatory documents, and industry sources. The final KPI set spans three impact areas, strategic, environmental, and economic, and is organised across seven themes: design and modularity, material circularity, cost and economic viability, lead times and availability, quality and performance, environmental impact reduction, and regulation and standardisation. System boundaries align with maritime assessment practices, applying cradle-to-gate for capital emissions, tank-to-wake for operational emissions, and excluding maintenance, transport, and end-of-life phases where data is insufficient or inconsistent.

The framework is demonstrated using a case study on a 20-year-old Damen ASD 3110 tug. Three refit strategies, refurbish (conventional diesel), remanufacture to hybrid propulsion, and remanufacture to full electric, are compared with representative newbuild vessels of equivalent concepts. Results show that all refit strategies significantly reduce project lead time (10–14 months vs. ~24 months), capital expenditures, and hull-related embodied emissions (saving 535–633 tonnes of CO₂ compared to newbuilds). Environmental performance diverges by propulsion type: refurbishing yields the lowest capital emissions but highest operational emissions, whereas electric remanufacture achieves zero operational emissions but the highest total cost of ownership. Hybrid remanufacture offers a balanced profile, reducing operational emissions by approximately 40% while maintaining economic competitiveness with refurbish strategies over a 20-year horizon. Sensitivity analyses indicate that relative performance depends strongly on energy prices, vessel lifetime assumptions, and regulatory context.

The study concludes that refits can serve as robust, circular alternatives to newbuilds for workboat-type vessels, provided that intervention scope, component availability, and operational profiles are appropriately matched. The proposed framework enables consistent evaluation of trade-offs and supports alignment with the EU Taxonomy and sustainable financing mechanisms. Recommendations include expanding environmental boundaries to well-to-wake analysis, improving data availability through digital product passports, refining economic KPIs, and validating the methodology across additional vessel types and shipyards.
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The shipping industry is responsible for a approximately 2 to 3% of the global greenhouse gas emissions. The International Maritime Organization (IMO) has set a goal in 2023 to reduce these emissions. This goal entails that the sector becomes net-zero by 2050, which should be partly realized by adding alternative fuels to the energy mix. In general, methanol, ammonia and hydrogen are considered as promising alternative fuels. However, all three have challenges, such as toxicity (methanol and ammonia) or explosivity (hydrogen). Additionally, none of them have volumetric and gravimetric energy densities that are close to the current standards of heavy fuel oil (HFO) and marine diesel oil (MDO).

Hydrogen carriers can solve these challenges. Hydrogen carriers are chemicals that store and release hydrogen on demand. There is only very little pure hydrogen gas on board, which reduces safety risks. Additionally, hydrogen carriers can store a relatively large amount of hydrogen, up to over 20 wt%, enhancing the volumetric and gravimetric energy density. Finally, the inherent properties of each hydrogen carrier determine their applicability. Since some carriers behave similarly to oil, they offer a significant advantage for existing bunkering and fuel-transport infrastructure.... ... Read more

The technological advancements in weapons and weapon systems continues to increase, and with these advancements the risk in safety increases as well. These weapons pose a great threat to naval task forces. In order to carry out missions safely, the task forces need to be equipped with defensive weapon systems. In this thesis the focus lies on air defense weapon systems. Originally, the selection of air defense weapon systems is done for a singular vessel, not taking into account the influence the other vessels in the task force may have on the operational effectiveness of the weapon systems in a group setting. This report presents an investigation into the selection and distribution process of weapon systems across a task force, while balancing the effectiveness and the costs of the weapon systems. The developed model utilizes a Weapon-Target-Allocation model in combination with the NSGA-II algorithm to generate the selection and distribution of weapon systems across the task force. ... Read more

The growth of the offshore wind market is accompanied by larger wind farms, whose electricity needs to be transported to shore.
Offshore converter stations are used for combining and converting the electricity generated from the wind farm for transport to shore.
The increase in the electricity produced by wind farms has led to converter stations growing as well.
This creates an issue, as for many current lifting vessels they are becoming too heavy to lift and place offshore.
Furthermore, new wind farms are currently still being built in shallow water, so vessels should be designed taking this into account if they are to place the converter stations.
As lifting by crane is preferred in the industry, this research looks into the use of semi-submersible crane vessels for lifting converter stations, as these are the largest crane vessel category and have the greatest lifting capacity. \par

Existing semi-submersibles are designed for operating in deep water and thus with little concern for limited water depth.
Consequently, current vessels have large draughts for working in rough seas but are not able to work in the shallows.
The performance of semi-submersibles in shallow water is a little researched topic, both in terms of designing these vessels for this condition as well as operating them at limited draught.
For this reason, this research proposes a new early-stage design model that includes the fundamental limitations for lifting in shallow water and addresses the research question:
\emph{How can the design of semi-submersible crane vessels be improved to lift at least 11,000 tonne substations in shallow waters of less than 30 m in weather conditions with significant wave heights of up to 2.5 meters?}
To answer this research question, the research looks to identify trends of optimized vessel parameters for the design of semi-submersibles for use in shallow water.\par

To find optimized designs for the lifting of converter stations in shallow water, a parametric model will be made within this research, which is then optimized.
This model will make use of the IOC-SAMO-COBRA algorithm to find designs that are optimized for three conflicting objectives.
These objectives are the light weight of the vessel, the water depth that it requires to lift a representative converter station and the operability of this vessel in waves at the required draught.
Applying these objectives, Pareto optimal solutions will be calculated for this situation.
By analysing the results of the model, trends are found for the optimum configuration of the vessel parameters for lifting 11,000 tons converter stations in shallow water.
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This thesis compares maintenance strategies for the Royal Netherlands Navy to optimize cost, man-hours and downtime. A decision support model was developed to evaluate different mixes of Corrective Maintenance (CM), Time-Driven Scheduled Maintenance (TDSM), and Condition-Based Maintenance (CBM) using SAP data and expert input. Results show that CBM application (~20–50%) reduces long-term costs for high-criticality systems, while man-hour efficiency sometimes favors more CM due to underreported labor in existing data. The model supports tailored, data-driven maintenance planning across vessel types and system groups. ... Read more

The design of large catamaran sailing yachts requires careful balancing of aesthetics, comfort, and performance, with the wet deck geometry playing a decisive role in resistance, motions, seakeeping, and slamming behavior. In this work, a method is proposed to enhance the estimation of wet deck geometry for large catamaran sailing yachts in an early design stage. While the operability of such catamarans is primarily driven by passenger comfort, the influence of wet deck geometry on motions, seakeeping, and slamming was identified as the main factor limiting vessel operability. Four key (non-dimensional) parameters, including wet deck height (h/L), hull separation (s/L), demihull beam-to-draft ratio (b/T ), and the starting position of the wet deck relative to the bow (Lswd/L), were systematically varied, resulting in 295 design configurations. Vessel performance was evaluated using a comfort operability index (cOI), which quantified the percentage of time a vessel could operate within the predefined comfort limits. The cOI was derived from seakeeping criteria, including effective gravity angle, motion sickness incidence, vertical and lateral accelerations, and slamming probability. Response amplitude operators (RAOs) at the center of gravity of each design were obtained using Maxsurf Motions, supplemented by an in‑house Python post‑processing tool to evaluate the seakeeping criteria across multiple onboard locations. An engineering correction was applied to heave motions in beam seas. The analysis covered three vessel lengths (50, 60, and 70 m), three headings (beam, bow‑quartering, and head seas), and representative sea states for the Mediterranean (Jonswap spectrum) and Atlantic (Bretschneider spectrum). Results showed that increasing vessel length consistently improved cOI, particularly in head and bow‑ quartering seas. Among the wet deck parameters, s/L strongly influenced lateral acceleration and effective gravity angle in beam seas, while b/T and Lswd/L significantly affected motion sickness incidence and vertical acceleration in head and bow‑quartering seas. Higher b/T ratios generally improved comfort, though the impact depended on vessel length, heading, and sea state. Lswd/L exhibited an initially positive but ultimately negative influence at higher ratios, while h/L showed an impact only in beam seas under Mediterranean conditions. Differences between the Jonswap and Bretschneider spectra were modest, with the Atlantic spectrum yielding slightly higher cOI values and reducing the limiting role of motion sickness incidence. Across all conditions, forward onboard locations emerged as the most critical for limiting comfort. By quantifying the impact of wet deck geometry parameters on operability, this study established a methodology that provided deeper insight into the influence of wet deck parameters during the early design stage. While the present analysis excluded sail forces and steady heeling angles, these aspects could be integrated into the framework of this study in future research. ... Read more

This thesis develops and demonstrates a mission-oriented, early-stage design framework for mid-size (40–90 [m]) Offshore Patrol Vessels (OPVs). The approach integrates hybrid scaling (geometric and targeted parametric variation) with multi-objective optimisation (MOO) in a Systems Engineering / Set-Based Design (SE–SBD) workflow. A parametric parent-hull model was implemented in CAESES and varied in principal dimensions and selected hull parameters. Performance was evaluated using Holtrop–Mennen resistance, intact-stability (GZ) analysis, and strip-theory RAOs aggregated into a multi-heading Seakeeping
Index (SKI). The optimisation process combines Design of Experiments (DoE), surrogate modelling, and a MOGA-based global search. Objectives reflect key drivers (SKI, Stability Index (SI), total resistance RT , and lightweight LW T ), while feasibility is enforced through GM /B limits, roll-period (Troll), and a range constraint.
Verification through hypervolume convergence and trend analysis confirmed robust optimisation behaviour, while validation against tank, CFD, and stability booklet data for a 45 [m] reference OPV demonstrated geometric fidelity and early-stage accuracy. The framework efficiently generates Pareto sets that reveal trade-offs between endurance, comfort, stability, esistance, and weight, supporting mission-aligned design choices.
The main contribution of this work is the development of a robust, adaptive, and mission-driven optimisation framework for OPVs. It explicitly integrates nonlinear scaling effects, dynamic stability criteria, and mission requirements within a single optimisation envelope. Beyond reproducing established naval-architectural behaviour, the framework advances early-stage practice by treating SKI and SI as explicit optimisation objectives and by embedding range and Troll as feasibility constraints. Its adaptive structure allows objectives, variables, and constraints to be tailored flexibly to owner, shipyard, or designer requirements, making it a practical decision-support tool for concept design. ... Read more

This thesis investigates how alternative fuels and energy reduction technologies influence the technical and economic viability of research vessels under market uncertainties and varying operational profiles. The study addresses the growing need for decarbonisation in the maritime sector, where research vessels face particular possibilities due to limited regulatory requirements and constraints due to their demanding mission requirements.

Research vessels, which are exempt from many regulatory emission frameworks, operate under highly variable mission profiles that challenge conventional decarbonisation approaches. The review identifies a significant gap in existing studies, which typically overlook the unique operational demands of these vessels.

The literature analysis evaluates a wide array of fuels - including fossil based fuels with lower carbon intensity such as LNG and LPG, renewable, diesel like fuels as HVO, hydrogen carriers as ammonia, hydrogen, and sodium borohydride, alcohol fuels as methanol, as well as metal-based fuels like iron powder -, wind assisted propulsion systems, and energy reduction methods as exhaust heat recovery and solar systems. Assessment is done on physical and chemical properties, emissions, safety, technological readiness and availability, and costs.

To handle the complex and uncertain decision environment, the study proposes the Many Objective Robust Decision Making Framework combined with an Epoch-Era Analysis that models the most important uncertainty, namely the various operational profiles. This methodological foundation allows for evaluating the technical and economic feasibility of many different propulsive combinations across a wide range of plausible futures.

The subsequent analysis shows that no single configuration is universally optimal across all conditions. Fossil and diesel-like fuels such as LNG and HVO remain technically feasible but offer only slight emission reductions. Methanol-ICE configurations emerge as the most robust low-carbon option, offering technical feasibility across all scenarios and significant emission reduction potential. Ammonia-ICE solutions perform well under lower requirements and can approach carbon neutrality if sustainably produced. The integration of energy reduction technologies such as exhaust heat recovery and wind-assisted propulsion improves performance, but effects remain context-specific and do not fundamentally alter the main trade-off’s between cost and emissions. The analysis further shows that blended fuels (e.g., grey/green methanol or ammonia) can serve as transitional pathways, enhancing economic viability while preparing vessels for a green fuel future. A design-oriented iteration of the MORDM indicate that hull form adjustments can improve robustness, however, more detailed calculations need to be done.

In conclusion, the findings underline that future-proof research vessels will need to adopt technically feasible, robust fuel strategies that enable compliance with long-term climate goals. Methanol, and to a slightly lesser extent ammonia, currently offer the most promising pathways, while fossil and diesel-like fuels cannot ensure sustainability under future conditions. ... Read more

Wind assisted vessel hull optimization is more expensive than traditional vessels. This thesis tests if multi fidelity modeling may be a solution to reduce the computational cost of optimizing wind assistedvessel hulls. A Bayesian optimization framework was coded that can use both single fidelity and multi fidelity data. A surrogate test problem of a 100 meter long wind assisted vessel was created based on CFD data and an empirical model. The first experiment compared the performance of the single and multi fidelity algorithms. The second experiment evaluated the impact of a better low fidelity by using weighted averages of the CFD and empirical as the low fidelity model. In the third experiment, the resulting vessels from optimizations with CFD and empirical models were compared to validate the necessity of including CFD in the optimization of wind assisted vessels. The results of experiment one show that multi fidelity is only slightly faster, but has a larger spread meaning the slowest optimization takes longer. Experiment two showed that a better low fidelity model drastically reduces the number of iterations needed to perform an optimization. Experiment three showed that the vessels optimized using CFD differ significantly from those optimized with empirical methods. Thus, multi fidelity modeling provided very limited improvements for the optimization of a wind assisted vessel when using empirical models and CFD. Significant improvements are possible with better low fidelity models. Lastly, empirical models used for wind assisted vessels are have limited usability for optimization. ... Read more

Modularity is often mentioned as a method to make a vessel’s design flexible during its lifetime. However, literature often focuses on ways to apply modularity to naval vessels instead of asking if modularity improves the vessel, or the organizational process, at all. This paper aims to build a framework to give the naval architect valuable insights into the possible benefits and the technical impact of modularity application. When a system is
deemed a feasible module, a final evaluation is performed to assess if the modular variant of the system actually improves the vessel or the organizational process.

This research presents a framework consisting of a Modular Function Deployment (MFD), Analytical Hierarchy Process (AHP), and Knowledge Based Engineering (KBE) model to assess the suitability and technical feasibility of modular systems. The MFD aims to identify high-potential modular systems based on modularity drivers defined and rated by the naval architect. Next, the AHP aims to map the most important functions of the vessel. Since modularity always comes with increased weight, the naval architect can use the AHP to ask
themselves if the system fulfills a function that is important enough to embrace the increased weight. With the KBE model, the technical impact of modular systems can be assessed in terms of weight, estimated draft, and stability. When a system scores high on the MFD, it indicates the system would benefit from modularity. When its accompanying function scores high on the AHP, it indicates the system fulfills an important function. The technical impact of making the system modular can be assessed with the KBE model. If the technical impact is
deemed acceptable, the system can be labeled as a ‘feasible’ module. The final effectiveness assessment will indicate if the feasible module actually improves the vessel’s design or the organizational process. This way, a framework will be developed which gives the naval architect valuable insights into the potential benefits and costs of modularity.

A case study will be presented on a landing platform dock and the future air defender (FuAD) of the RNLN. Results show the FuAD has higher-potential systems for modularity, so the KBE model is applied to only the FuAD. In the KBE model, an air surveillance radar and Laser-Directed Energy Weapon (LDEW) are modeled as a non-modular system and then as a modular variant. This way, the impact of making a system modular is assessed. The KBE model results in a technically feasible module for the air surveillance radar and LDEW. The final effectiveness assessment results in a preference for a non-modular air surveillance radar and a modular
LDEW. This shows that modularity does not necessarily improve the system and a structural way to approach modularity and compare it to a non-modular variant is required.

The framework can be applied to a wide variety of vessels, including commercial vessels. The framework uses generally applicable methods, and by combining them in a structural way the decision-making on whether to use modularity or not can be improved. For naval vessels, the effectiveness depends on the intentions of the end user. By qualifying the expert opinion using AHP, both by identifying the most important functions and the final evaluation, this intention is integrated into the framework. This also personalizes the outcome: based on the intentions of the end-user, completely different outcomes can be retrieved from this framework. After computing the framework for a specific vessel type, the results can partially be applied to other vessel types, within the same organization due to the end-user intentions mentioned above, as well. If a modular system is preferred over the non-modular variant, this implies the other vessel types will also benefit from this system as a module. Since this system is already defined as an HLP in the KBE model, the system can easily be imported into another
design. The hull form can be easily changed as well since this already is an external Rhino file imported into the Python file. These factors make the framework applicable to a wide variety of different vessel types. ... Read more

Early-stage design is the most critical phase in a vessel’s development, as this is when many of the major decisions are made and locked in for the remainder of the design process. Most early-stage design frameworks are tailored to conventional vessels, aiming to explore a broad design space—essentially assessing numerous design variations. However, to evaluate such a wide range of design solutions, these frameworks often sacrifice accuracy in their analysis methods to allow for more design evaluations. Consequently, low-fidelity tools are typically used for early-stage design exploration.
For novel vessel designs, low-fidelity analysis methods are insufficient for accurately assessing performance, as they often fail to capture the new and sometimes complex physics involved. While increasing the fidelity of analysis methods leads to more accurate performance assessment, it also raises computational costs, making it impractical to evaluate a large number of design variations. Multi-fidelity models, which combine lower-fidelity methods with a high-fidelity analysis method, offer a promising solution for enabling higher-fidelity assessments earlier in the design process. Thus, this dissertation builds the architecture of a multi-design architectural framework for early-stage design of novel vessels... ... Read more

Due to recent legislative changes and shifts in global markets, the task of ship design has grown considerably more complex. The integration of groundbreaking technologies, such as remotely controlled or autonomous vessels, poses additional challenges during the concept design phase, primarily due to a lack of familiarity and experience with these technologies. Simultaneously, these advancements make designing a vessel that can consistently meet its objectives throughout its entire life cycle increasingly difficult.

In the early stages of the design process, designers often face the challenge of making critical decisions without fully understanding their potential consequences. This situation is compounded by the increasing costs associated with these decisions and their influence on design freedom. Consequently, the conceptual design stages become especially crucial, as making changes later in the shipbuilding process can result in significant cost escalation for the project.
Considering the various factors impacting the ship design process, there arises a necessity for a novel methodology empowering designers to assess the operational capabilities and performance of conceptual designs during the early stages of ship design.

The presented report introduces the project titled 'Validating Operational Scenarios Through Simulation' and presents findings from a literature review on the utilization of simulation in early-stage design processes.
The introduction chapter begins with an initial description of the problem to be addressed, introduces the involved company, and outlines the motivation behind the project. Following the introduction, the results of the literature review are presented.
The second section aims to answer the first set of research questions by examining the current implementation of simulation software within design processes and presenting available options for software to be utilized in the project. The process of selecting the software is then outlined, along with the conclusions drawn from the research conducted.
Subsequently, the formulated methodology is described, containing all steps necessary to structure the workflow during evaluation. The following chapter details the anticipated method of introducing the formulated method into existing design processes, including the main method of evaluation through simulation and the method of integration, using a case study example.
Finally, the last chapter concludes the report by providing considerations from the entire process and presenting recommendations for potential improvements of the formulated process. ... Read more

To reduce the environmental impact of the maritime sector, the International Maritime Organization (IMO) has established emission limits and ambitious sustainability targets. While superyachts are currently exempt from many of these regulations, they must align with IMO’s objectives to establish the yachting industry as a responsible sector and adapt to the increasing application of these emission limits. Focusing only on new builds is not sufficient to meet ambitious targets, and sustainable refit of existing yachts is also essential. This applies not only to motor yachts but also to sailing yachts, which face unique challenges due to limited space which further complicates integrating alternative fuels like methanol or hydrogen, given their lower energy density. Despite various studies exploring alternative energy solutions, there remains a research gap in understanding the trade-offs associated with different energy configurations installable in a refit to minimize energy demand and emissions. To address this, an assessment model that evaluate technical feasibility, emissions, docking time, and Total Cost of Ownership (TCO) for different energy configurations is developed. Results from the assessment model, applied to two Royal Huisman sailing yachts of different size across various owner profiles, reveal that integrating alternative energy solutions requires significant reductions in energy demand. Feasible configurations range from using a single fuel HVO configuration for conservative owners to hybrid solutions involving HVO and methanol for more open to changes owners. Ultimately, owners willing to implement various energy reduction methods can achieve several feasible and sustainable configurations. ... Read more

Technological advancements are increasing system complexities, posing challenges for modern warship design. Early-Stage Ship Design (ESSD) is a vital stage, involving critical decision-making with limited information. The early-stage design of warships entails intricate decision-making considering temporal influences, interdependencies, external factors, trade-offs, high costs, evolving requirements, and other challenges. Developing well-defined system architectures is essential for managing these complexities. Model-Based Systems Engineering (MBSE) is pivotal for overcoming precision issues, inconsistencies, and difficulties in maintaining and reusing information associated with conventional document-centric approaches in systems engineering (SE).
Despite the growing popularity of MBSE, the maritime industry continues to rely on traditional document-centric approaches, lagging behind other sectors in adopting MBSE. These challenges stem from a lack of empirical evidence demonstrating MBSE's full benefits and confusion regarding its implementation practices. Moreover, there is a lack of comparative studies that assess how well MBSE tools are tailored for naval warship design. Thus, this research explores the value of MBSE in the early design stage of naval vessels. Specifically, the research aims to validate and demonstrate MBSE's benefits in developing systems architecture for warships, focusing on operational, functional, logical, and physical perspectives within the context of ESSD. By analyzing industry approaches and utilizing two representative modeling tools, this thesis provides practical insights, clarifies MBSE practices, and promotes its effective implementation in future naval design projects.
A structured research process is formulated to achieve the thesis objective. It begins by defining the mission, capabilities, and requirements. For illustration purposes, a hypothetical Landing Platform Dock vessel mission is chosen, necessitating the creation of fictitious capabilities and requirements. MBSE tools Capella and CDP4-COMET are then selected for this analysis. Next, a metamodel is established for a unified understanding among stakeholders, guiding decision-making throughout the design process. Once the baseline models are constructed, the validation and verification capabilities of the tools are evaluated. The baseline models are modified to simulate the dynamic nature of warship design. Finally, the tools are systematically assessed based on selected key MBSE factors: consistency, traceability, flexibility, and trade-offs.
Transitioning to conclusions, the analysis reveals that both tools effectively validate anticipated benefits. By synthesizing the knowledge gained, it is concluded that MBSE can enhance and accelerate the design process during the early design phase of warships. Capella demonstrates superior performance in the early design stages, whereas CDP4-COMET excels in the latter design stages. This emphasizes the critical role of integrating MBSE tools to enhance design outcomes, leveraging their strengths across diverse phases effectively. Thus, integrating MBSE tools and establishing a unified source of truth is one crucial aspect of advancing MBSE in ship design. Further recommendations are detailed in the thesis.
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The maritime industry is progressively transitioning towards sustainable practices, with a significant focus on integrating zero-emission power generation systems. However alternative fuels and technologies implementation on large scale is still pending.
Ships and especially yachts today are designed just for their immediate needs with no future consideration taken into account. This thesis addresses the need for adaptable power room designs in superyachts, facilitating the integration of zero-emission power generation systems as technology evolves. The primary aim is to develop a design method enabling easy retrofitting and future-proofing of yacht power rooms.
The research identifies the current design methods limitation where power rooms are designed for specific scenarios without considering future adaptability. To address this gap, the thesis proposes a three-step design method: layout concepts, design rationale, and a layout evaluation model. This model evaluates power room layouts based on Connection Costs and Retrofit Costs, offering indicators to assess future-proofing capabilities of power rooms arrangements.
A future-proof road-map based on four different scenarios was identified. By applying the design method to these scenarios, various layout concepts were developed, refined based on expert opinions and then evaluated with the model. The results highlight key practices for future-proofing power rooms, such as prioritizing connections between zero emissions power generation systems and auxiliary systems, pre-arranging transport equipment, and designing access openings to facilitate easy retrofitting.
This research underscores the need for a flexible approach to power room design, ensuring superyachts can transition smoothly to zero-emission operations in the coming years.
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