Polar research vessels demand increasingly greater endurance due to their special scientific research missions. A marine plant factory solution is proposed to address the problem of vegetable shortage for long-endurance polar research vessels, ensuring continuous supply of vegetables. The applied research of plant factory technologies for polar research vessels is conducted by discussing the key technologies, environmental control requirements and type selection of marine plant factories. A design method for the plant factory on long-endurance polar research vessels is then presented to provide references for ship designers.

The wheelhouse windows will be iced by seawater droplet and climatic conditions such as rain and snow for vessels operating in extreme cold environments. It will obstruct the view from the wheelhouse and thus threaten the navigation safety, making the deicing design for the wheelhouse windows critically important. Aiming at optimizing the deicing effect of the wheelhouse windows under extreme cold environments, it studies the causes of icing on the surface of the wheelhouse windows. Using this as input conditions, the electric heating deicing of the wheelhouse windows are numerically simulated and analyzed to provide the deicing effect of different electric heating powers under different external ambient temperatures. An electric heating deicing solution is finally proposed for the wheelhouse windows under extreme cold environments.

A ship interior outfitting design system using virtual simulation technology is developed to address the limitations of the traditional ship interior outfitting design system, including lack of intuitiveness, poor interaction and long design iteration cycles. 3ds Max has been used for 3D modeling, and the realism of the model and the real-time nature of the system are considered through refined modeling and optimization processing. A virtual environment based on the Unreal Engine 4 is established to complete the model import, material allocation, collision setup and lighting optimization, together with efficient connection to a MySQL database through C++ plug-ins. The system integrates the functions of resource management, dynamic adjustment of design schemes and perceptual engineering evaluation, and develops diversified interactive logic through blueprint technology to improve the user experience. The test results show that the system can accurately present the three-dimensional model and material effects of the interior outfitting design, realize the function of real-time interaction and perceptual engineering evaluation, thereby meeting the basic requirements of ship interior outfitting design. Users can intuitively adjust design schemes and obtain visualized evaluation feedback through the system. The system has good intuitiveness and operability, enhancing the presentation quality of the design scheme and user experience. It provides an innovative solution for the ship interior outfitting design.

This paper optimizes the scheme of side-by-side mooring operation for a special SWATH. Through numerical simulation and model tests, we analyze relative motions, mooring line tensions, and fender loads between the SWATH and single-body ship, aiming to guide the side-by-side mooring operation. The results show that the displacement difference of SWATH significantly affects the horizontal motion of the barge and the motion of SWATH itself. Changes in wave direction have a notable impact on the horizontal motion of both ships. Under the same relative motion, short mooring lines and fenders bear large loads. Therefore, it is recommended to select optimal wave directions (e.g., head seas) and loading states for operations. Beam seas (90°) pose the highest risk due to excessive fender compression. The research provides references for the design and optimization of side-by-side operations between SWATH and ships.

Numerical simulation on the static and dynamic characteristics of the rigid base has been conducted based on finite element analysis (FEA) to verify the reliability and safety of the rigid base of the designed marine diesel generator set. The modeling of the components and BOM assembly is completed by using the NX11.0 software integrated in the Teamcenter platform, according to the schematic diagram of the rigid base from the selected design. After simplifying the component features, the BOM assembly is imported into FEA software for static and dynamic modal simulations of the rigid base. The calculation results show that the static strength and stiffness of the designed rigid base meet the operational requirements, and the first six natural frequencies are much higher than the external excitation frequency. There will be no resonance phenomena, and the dynamic strength and the stiffness of the structure are reliable, verifying the rationality of the selected design. It allows for the early evaluation and prediction of the reliability and safety of the structural performance of the rigid base. It provides theoretical support for subsequent product processing and manufacturing and offers direction for further optimization of the product design.

Communication, positioning and navigation (CPN, referred to as “communication and navigation” in Chinese, where “positioning” is integrated into “navigation”) are crucial for all marine vehicles, and it is more essential for under-ice vehicles operating in polar regions. As human beings step into the polar regions with higher latitude and larger depth, underwater vehicles are more active in under-ice scientific surveys. However, compared to open-water environments at lower latitude regions, the under-ice CPN in polar regions is very special and the relevant CPN technologies also face unique challenges. Hence, the development of under-ice CPN technologies in polar regions also differs from that in other regions. This study reviews the current status and challenges of under-ice CPN technologies in polar regions and provides a prospect for their future developments.

The length-to-breadth ratio ( L/ B) of a heavy icebreaker is generally between 4~5. The applicability of conventional calculation formulae for calculating wave loads on hull girder is limited. The characteristics of heavy icebreakers hull lines differ significantly from those of vessels designed for open waters. Numerical methods are consequently required to study the characteristics of wave loads on hull girder. A time-domain Rankine source method accounting for speed is employed to predict the wave loads on hull girder by using the hydrodynamic software WASIM. Both the long-term values of linear wave loads and the direct calculation results of nonlinear wave loads are obtained. Comparisons are then made among the long-term linear wave loads (after nonlinear correction), the directly calculated nonlinear wave loads and the standard values. The results show that the long-term linear vertical wave bending moment is approximately 1.4 times the standard linear value, and the long-term linear vertical wave shear force is 1.9 times that of the standard linear values, owing to the unique hull lines of heavy icebreakers. It is indicated that the standard formulae cannot provide a reasonable evaluation of the wave loads on the hull girder for these vessels. From a practical engineering design perspective, the long-term linear vertical wave loads (after non-linear correction) at a speed of 5 knots are adopted as the design wave loads of the hull girder for the evaluation of the overall strength of the hull structure. The non-linear effect of the sagging wave bending moment is significant, resulting in special consideration of the structural buckling of long superstructures during the check of the longitudinal strength of the hull under sagging condition.

Extrusion between the side structure and the level ice is one of the most common scenarios encountered by polar ships. It is of great significance for the design and operation of polar ships to explore the mechanism of the extrusion between the level ice and the broadside. A numerical simulation model of the interaction between the level ice and the broadside is established by using the discrete element method in the current study. The rationality of the numerical model is verified based on the results of a model test on the ice loads during the broadside extrusion conducted in an indoor ice tank. The influence of the variation of the angle between the level ice drift direction and the ship's heading on the ice loads during the broadside extrusion is studied and analyzed based on established numerical model of the extrusion between the level ice and the broadside. The mechanism of the broadside extrusion and the distribution law of nonlinear ice loads are discussed. It can provide technical support for predicting ice loads and structural responses in the scenario involving the extrusion between the level ice and the broadside.

The icebreaker needs to adjust the ship's longitudinal attitude to accomplish icebreaking during missions. To accomplish the rapid longitudinal adjustment of the ship, a multi-medium method is adopted to complete the ballast/deballast process for the fore and aft tanks. The ballast process is based on a hybrid method using ballast pumps and gravity flooding, while the deballast process is based on a hybrid method using ballast pumps and air compressors. For the ship's ballast/deballast system, a network model for the longitudinal attitude adjustment is established based on the designed multi-medium ballast/deballast method, considering both the fore and aft tanks. Simulation analysis shows that compared with the pure ballast pumps, the multi-medium method increases the ballast process speed by 4% and the deballast process speed by 25.6%. The multi-medium ballast/deballast method can greatly shorten the time required for rapid longitudinal attitude adjustment for icebreakers, thereby enhancing their operation flexibility.

With the continuous development of Arctic resources, the risk of collision between polar ships and level ice is increasing. Different icebreaking methods will have different effects on the hull structure under variable ice thickness. At present, the judgment of icebreaking methods is mainly based on the icebreaking levels in polar ship specifications. It is difficult to study the maximum icebreaking thickness and the speed of different icebreaking methods without classifying the icebreaking levels. The equation between the propulsion force and speed is therefore derived based on the force balance relationship. A method for judging the icebreaking method of polar ships is proposed by combining with the safety design of hull structure strength. The maximum cruising ability of the continuous icebreaking for a polar icebreaking transport ship has been determined. The reliability of the determination of the icebreaking method is verified by comparing with the model experimental results. The speed range for continuous icebreaking and impact icebreaking methods has been divided under different ice thickness conditions. It provides theoretical support for the icebreaking design and navigation of polar ships.

With the promotion of carbon peak and carbon neutrality strategy, offshore wind power is developing towards deep waters, facing server challenges of strong winds and waves. Traditional personnel transportation methods have significant safety hazards in harsh sea conditions, seriously restricting the high-quality development of project construction. It is therefore necessary to explore new methods for offshore resource support under complex sea conditions. Based on the fractal characteristics of waves, a fractal-wave compensation adaptive algorithm is proposed by combining with the active wave compensation and adaptive principles. An adaptive compensation trestle model is then established on the basis of this algorithm. The adaptive operation and maintenance ship is transformed through the installation of adaptive compensation trestles. Compared with the traditional operation and maintenance ship, the adaptive operation and maintenance ship transformed from an offshore wind power maintenance ship in the South China Sea can effectively solve the safety issues of personnel boarding. At the same time, the utilization rate of the sea window is increased by 3.5 times, the efficiency of the transfer personnel is increased by 3.3 times, and the comprehensive economic benefit is increased by 10.3%. The adaptive operation and maintenance ships have significant advantages in operations under complex sea conditions. It can provide resource support for subsequent deep-sea offshore wind power projects.

Zooplankton nets are fundamental tools for biological oceanography, and their sampling quality directly affects the evaluation accuracy of species composition and ecological function. The technical evolution of zooplankton nets from early vertical hauls to modern multi-net platforms (such as MOCNESS and Multinet) has been reviewed to highlight significant advancements in mechanical control, telemetry, and depth-resolved sampling. It analyzes the complementary role of non-contact technologies, such as optics, acoustic, and environment DNA, to traditional nets, emphasizing the continuing necessity of net sampling in species identification and data verification. It is further proposed that the future development of zooplankton nets should integrate sensing systems, artificial intelligence, and sample-preservation technologies to develop a “smart net” system for efficient, low-bias and quantitative sampling of meso- and macro-zooplankton.

With the continuous advancement of decarbonization in the maritime industry, especially after MEPC 80 setting the goal of achieving net-zero emissions by 2050, the application of low-carbon/zero-carbon fuels has become a major focus. The large-scale adoption of energy sources such as liquid ammonia, liquid hydrogen, green methanol, and LNG is gradually accelerating. Nuclear energy, as a clean energy source, is also of increasing interest to the maritime industry. With the development of fourth-generation small modular reactor (SMR) technology, the inherent safety attributes of reactors have been enhanced while reducing the risk of radiation leakage, making nuclear energy a possible propulsion method for large commercial vessels. Starting from the decarbonization needs of the maritime industry, the current use of nuclear energy as a marine propulsion method has been introduced with a focus on the recent technological developments of fourth-generation SMRs. It particularly analyzes their development potential as marine small reactors and proposes key factors that should be considered for their application onboard ships. It focuses on the unique application advantages of molten salt reactors (MSRs), especially thorium-based solid-fueled MSRs, for civilian ships. It also analyzes and prospects the application of SMRs in Suezmax oil tankers, ultra-large container ships, and floating power generation platforms. It can provide theoretical support and references for subsequent engineering applications of nuclear power in ships.

As a strategic national asset ensuring the security of China’s energy resources, the summer extreme heat environmental condition and complex air flow composition of the ocean drilling vessels have become one of the key challenges in the design and construction. By establishing the balance formula of air volume inside a galley, this study sorts and analyzes the airflow parameters such as air conditioner air supply, air intake outside and inside the cabin and air mechanical exhaust. Based on the cooling capacity calculation method for fresh air conditioners specified in ISO 9943:2009, and incorporating personnel comfort requirements, this study proposes a solution for adjusting air conditioning cooling capacity parameters under extreme heat conditions exceeding standard environmental design specifications. Using an ocean drilling vessel as a case study, calculations were performed to develop recommended cooling capacity parameters for such extreme conditions on this vessel. This provides a reference for engineers to clarify air flow composition in complex cabins and to select appropriate cooling equipment under extreme heat environments.

Ropes are critical components for mooring ships and offshore floating structures under periodic axial loads. To investigate the tensile properties and stiffness characteristics of deep-sea mooring polyester ropes, they are categorized into three stages: preloading, initial installation, and aging. Initially, the tensile properties of the ropes under static loads are examined, quantifying strain and reversible elongation rates at each stage and comparing mechanical properties of polyester ropes with those of nylon ropes. Subsequently, creep coefficient solution tests under varying tensions are designed, establishing a quasi-static stiffness empirical equation with consideration of the rope creep coefficients. Experiments have shown that the mooring ropes still undergo reversible elongation after unloading, and sufficient break-in period of the ropes can reduce their inherent deformation and increase their structural stability. Static stiffness of the ropes increases with loading time and force until it reaches a constant value. Polyester ropes have greater stiffness, smaller deformation and more stable structure than nylon ropes, making them more suitable for deep-sea mooring. The findings enable comprehensive analysis of rope stiffness evolution throughout its service life, thereby offering references for reasonable design of deep-sea taut-line mooring systems.

High-precision localization of pipeline damage using acoustic emission technology in the marine environment remains challenging. A hybrid path optimization-based localization method for structural damage source localization is proposed. First, the short-time Fourier transform (STFT) maps acoustic signals into the time-frequency domain, with K-means cluster grouping signals to separate different damage sources. Subsequently, the ROTH dual-weighted cross-correlation algorithm is employed to accurately estimate the time difference of acoustic wave arrivals at sensors under strong noise conditions, extracting temporal characteristics of the acoustic waves. Next, an initial propagation path is generated via the Rapidly-exploring Random Tree (RRT) algorithm, and further optimized through an improved D* dynamic path optimization algorithm to determine the optimal propagation path. Finally, acoustic emission source locations are calculated by using hyperbolic equations and weighted least squares based on geometric localization methods. Experimental results demonstrate that this method can accurately locate the structural damage source in complex environments, significantly outperforming traditional approaches.

The Western-Pacific region contains abundant polymetallic nodule resources. Effectively exploiting these resources is of great significance for the metal resources supply in China. To verify the feasibility of deep-sea mining and achieve commercial mining, it is necessary to conduct in-situ sea trials of the mining system in the mining area and develop environmental monitoring procedures to assess the impact of the mining operations on the environment. This study focuses on the monitoring content and monitoring plans by establishing a set of environmental monitoring and impact assessment procedures. It details the environmental monitoring procedures for sea trials across pre-trial, in-progress, and post-trial phases. The results show that polymetallic nodule mining is feasible in the Western-Pacific region. However, the impacts of mining plumes and sediments on the bottom marine ecosystem should be considered carefully, alongside the formulation of effective mitigation measures.

The Hangzhou-Ningbo Canal is of great significance to the economy and material circulation in the eastern Zhejiang region. This study focuses on the automatic modeling and hull form optimization of container vessels sailing in the Hangzhou-Ningbo Canal by coupling CAESES with computational fluid dynamics (CFD). First, the hull structure is deformed based on semi-parametric modeling. A new hull form is iteratively generated according to the geometric parameters given by the optimization algorithm. In each iteration, the hydrodynamic performance of the hull model is solved by using CFD software to provide geometric parameters for the next iteration. The optimal hull form is eventually identified in the geometric configuration space through this iterative process. The results show that the optimized hull form achieves a drag reduction of 5.8%, and the pressure distribution on the hull surface is significantly improved, with a reduced negative pressure area and less stress concentration. This study can provide theoretical and technical support for the hull form optimization of inland container vessels.

The design ideas, key technologies and construction process of a shipborne paleomagnetic laboratory in low magnetic field environment are elaborated based on the construction of a paleomagnetic laboratory for an ocean drilling vessel. The article begins with a brief introduction to the basic principles and research significance of paleomagnetism, and the current technical development status of shipboard paleomagnetic laboratories. The overall design scheme and construction process of the shipboard paleomagnetic laboratory are then elaborated in detail, including the simulation design of the paleomagnetic laboratory, the optimization of the laboratory layout, the innovative structural design, the magnetic shielding technology, the vibration and noise reduction control, and the key construction technology. The key performance indicators, such as the average residual magnetic field in the laboratory and the overall shielding effect, meet the requirements for shipboard paleomagnetic laboratories through the optimization of structure, equipment and material selection, and the innovative application of technologies of hole optimization simulation design, flexible support design, and special construction technology for shielding layers. Finally, a scientifically reasonable debugging and measurement scheme is introduced for detecting the magnetic shielding effectiveness of the shipboard paleomagnetic laboratory, which fully verifies the feasibility and effectiveness of the design and construction of the low-magnetic environment paleomagnetic laboratory.

To enhance the stability and safety of the underwater structure of the submersible pressure hull, this study focuses on its multi-objective optimization design, aiming to achieve a synergetic improvement of quality, strength and stability. The parametric analysis process is used to analyze the initial ring-stiffened pressure shell scheme, using the optimal Latin hypercube sampling method to explore the influence of design variables on target responses. A high-precision response surface model and a multi-objective optimization model are also established, thereby enabling the multi-objective optimization of the pressure hull using the NSGA-II genetic algorithm. The results show that among the four optimized schemes, the weight of scheme A and scheme C is reduced by 7.3 kg and 6.6 kg, respectively, while the ultimate strength of scheme B and scheme D is increased by 0.177 MPa and 0.031 MPa, respectively. It is confirmed that the multi-objective optimization method integrating response surface models and genetic algorithm can effectively improve the performance of submersible pressure hull. It can provide a valuable reference for the design of deep-sea exploration equipment.

The analysis object of this paper is a cylindrical pressure shell with a single orthogonally nozzle and reinforcement structures, consisting of a nozzle wall and an insert plate. Taking the non-iteration design process of the reinforcement structures of this cylindrical pressure shell as an example, this paper proposes a non-iteration design method based on the gradient boosting decision tree (GBDT). This work provides a reference for the design of structures without the need of iteration design process. The non-iteration design method proposed in this paper includes three parts: dataset generation, generation of the non-iteration design surrogate model, and development of a dedicated APP for non-iteration design. Firstly, a machine learning dataset is obtained by the parametric finite element analysis through ABAQUS-Python for the reinforcement structures of the cylindrical pressure shell. Then, based on the Gradient Boosting Decision Tree and the multi-output regressor, a non-iteration design surrogate model is generated based on the dataset. Finally, a dedicated forward design APP (HUST-FWD01) is developed to standardize the non-iteration design and verification processes for the reinforcement structures. The results show that the dimensions of the reinforcement structure can be obtained without the need of iteration by the non-iteration design surrogate model, which is generated based on the non-iteration design framework proposed in this paper. In the surrogate model, the maximum stress near the opening of the pressure shell is used as the input, and the dimensions of the reinforcement structures are the outputs. The verification examples show that the errors are all within 3% between model inputs and the FEA results corresponding to model outputs. The research results can provide a design method without the need of iteration for the reinforcement structures of cylindrical pressure shell with a single orthogonally hole as well as the structures akin to them.

Currently, marine security is becoming increasingly severe, with incidents of harassment, attack, and sabotage against vessels occurring frequently. Aquaculture vessels, operating long-term in deep seas, are particularly susceptible to various forms of harassment, attack, and sabotage, which seriously threaten their safe operation. Additionally, aquaculture vessels also face significant internal security risks. It is therefore necessary to establish a complete security system for the aquaculture vessels to ensure their safe operation. The potential security risks are categorized into external risks and internal risks based on the characteristics of an aquaculture vessel. Accordingly, it constructs the external and internal risk security systems, clarifies the overall composition and workflow of the external security system, and establishes a “scenario-personnel” double closed-loop laboratory security system, as well as proposes specific security measures against violent and terrorist crimes. From the perspectives of monitoring, emergency, and supervision, an integrated security system is established to ensure the safe operation of aquaculture vessels.

Emergency risk assessment provides a basis for offshore operators to identify hazards, reduce risks to an appropriate level and protect people from the impact of accidents. The aquaculture vessel will be affected by adverse natural conditions during navigation and operations, not only facing risks such as collision and grounding, but also encountering additional emergencies arising from engineering operations such as mooring operations and aquaculture farming. It is therefore necessary to carry out risk assessment for the emergencies it faces. Firstly, the characteristics of the aquaculture vessel is analyzed. Subsequently, the types, probabilities, causes, processes, and severity of potential emergencies throughout the whole process of the navigation and operation of the aquaculture vessel are examined based on these characteristics. Finally, a risk assessment of the emergencies faced by the aquaculture vessel is conducted to develop a FMEA worksheet by using the failure mode and effects analysis (FMEA) method. It provides valuable date decision support for emergency decision-making and emergency management system construction.

As the core equipment for deep-sea aquaculture, the hydrodynamic research on ship-shaped aquaculture cages is crucial for ensuring their structural safety and farming reliability under extreme sea conditions. This paper systematically integrates the framework of "theoretical research-numerical simulation-model validation" used in the hydrodynamic study of ship-shaped aquaculture cages and reviews the relevant hydrodynamic analysis theories. The research status is reviewed from three aspects: hydrodynamic responses of the hull and mooring system, hull structural strength, and fluid-structure interaction effects of the netting. Furthermore, the key challenges in the hydrodynamic analysis of ship-shaped cages are analyzed: the complexity of multi-physics strong-coupling modeling, the accuracy-efficiency trade-offs in netting simulation, the bottlenecks in predicting nonlinear responses under extreme environments, and the lack of full-scale validation data. Finally, four future research directions are proposed: developing a multi-field wave-structure-mooring-netting interaction model, advancing the refined modeling technology for complex marine environments such as typhoons and internal waves, introducing intelligent algorithms to optimize the dynamic response of mooring systems, and developing hydrodynamic optimization and control technologies for intelligent submersible systems. This review provides theoretical support for the hydrodynamic mechanism research and engineering safety application of ship-shaped aquaculture cages.

In underwater hull cleaning tasks, the detection and precise identification of fouling and obstacles by target detection technology are critical for enhancing the efficiency of automated cleaning. The current underwater-hull cleaning robots primarily rely on manual visual inspection for environmental perception and target localization, which imposes efficiency bottlenecks and safety hazards. An improved model, YOLO-HC, is proposed based on the YOLOv11 framework. The model enhances cross-scale feature extraction capability by constructing a Multi-scale Dilated Attention module (MSDA_C2PSA), optimizes multi-level target representation fusion by using a Bi-directional Weighted Feature Pyramid, and further improves detection robustness by integrating multiple attention mechanisms into the dynamic detection head. In experiments on a self-built underwater hull surface dataset, the model achieved 87.0% and 62.4% on the mAP@0.5 and mAP@0.5:0.95 metrics, with increases of 2.2% and 3.4% compared to the baseline model, respectively. It provides an accurate and efficient target detection method for underwater hull cleaning tasks, advancing the goal of intelligent and unmanned hull cleaning.

This article summarizes the four main stages of the development of international ocean scientific drilling: deep sea drilling project, international ocean drilling program, integrated ocean drilling program and international ocean discovery program, and introduces the main scientific achievements obtained during each stage. China also participated in the above stages, leading four voyages across three ocean scientific drilling projects, and achieved a series of scientific achievements in the South China Sea. The development of international ocean scientific drilling is closely related to the development of ocean drilling vessels. The development of worldwide ocean scientific drilling equipment is chronologically introduced with a focus on the technical characteristics of China's first ocean scientific drilling vessel, the “Mengxiang”. Finally, the development of the ocean scientific drilling technology is analyzed based on the development history of the ocean drilling and the update and iteration of the ocean drilling vessels. It can provide references for the development of the international ocean scientific drilling.

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.

The epidemic prevention assistant robot refers to an automated device designed to assist crew members in epidemic prevention. In maritime epidemic prevention, the application of such robots onboard helps reduce the workload of crew members and mitigate the risk of epidemic transmission. Based on existing technical documents and market product information, combined with practical requirements, this study analyzes the feasibility of deploying two conventional functions—delivery and disinfection—of epidemic prevention assistant robots on ships. It further compares and analyzes their advantages over alternative methods. To implement the delivery and disinfection function of the robots onboard, the adaptability of key technologies for these conventional functions of the epidemic prevention assistant robots is demonstrated and analyzed around the issues such as ship oscillation during navigation and limited compartment spaces. Technical recommendations for shipboard robot applications are then provided.

With the increase of the installed engine power and redundancy requirements, the specification of the engine room ventilation system has been expanded, imposing difficulties on the design and layout of the engine room. A compound engine room ventilation system is introduced by combining frequency conversion fans and water-cooled internal circulating system. The CFD method is utilized to simulate a ship under several basic working conditions, optimizing the parameters of engine room fans, the layout of engine room air coolers, and the nozzle angles of jet fans. The results show that the compound engine room ventilation system effectively reduces the specification of the engine room ventilation with improved economy and flexibility. It can provide a reference for the design of engine room ventilation system for similar vessels.

Hydrogen fuel cells have emerged as an important development direction for future marine power sources. With rapidly increasing complexity in ship power systems, traditional document-centric systems engineering methods fail to meet the research and development demands for rapid iterative of hybrid power systems. To address this, a design and verification method is proposed for the hybrid power system of hydrogen-fueled ships based on Model-Based Systems Engineering (MBSE) method. Firstly, the SysML language is employed to perform the hierarchical decomposition modeling at the overall, system and subsystem levels according to the requirement definition, functional analysis and logical design based on the overall engineering requirements. The functional logic rationality of the model is then verified through the integrated simulation verification of the model. Finally, a Simulink simulation model is built to simulate and calculate the performance parameters of the hybrid power system of the hydrogen-fueled ship. The feasibility of the design and verification process and the effectiveness for the design iteration of complex systems are validated on the hybrid power system of a hydrogen-fueled ship. It can provide a reference for the application of MBSE method in other ships.