Ship Engine Room Research Articles

Global Pipe Optimization for Ship Engine Room

Global Pipe Optimization for Ship Engine Room

Coupling CFD and VR for advanced firefighting training in a virtual ship engine room

Firefighting training using virtual reality (VR) technology has still not been used extensively in the maritime industry. One of the reasons lies in the inability of VR to accurately replicate the true dynamics of a fire. However, this shortfall can be effectively addressed by integrating computational fluid dynamics-based (CFD) models of fire spread into VR training simulations, thereby significantly enhancing the realism and educational value of these scenarios. In this study, a scenario of a fire spread inside the ship engine room has been developed. First, as a CFD analysis, whose results were then transferred to the VR environment. That approach has been tested with users who have noted that CFD-based fire gives a more realistic appearance than the generic modelled solely using the game engine.

Analysis of the Effect of Sound Dampening on Ship Engines Based on Tofu Dregs Composite Material (Glycine Max (L) Merill)

Noise in the engine room of a ship is a significant problem that can affect the health and comfort of crew members. This study aimed to evaluate the potential of tofu dregs as a sound insulation material in the form of a composite of carbon black and talak duco. The research method included making composite specimens with variations in composition, followed by testing the sound absorption coefficient using the impedance tube method. The results showed that the specimen with 30% tofu dregs, 45% carbon black, and 25% talak duco produced the highest sound absorption coefficient of 0.24. These findings show that tofu dregs have potential as an environmentally friendly and economical sound insulation material and can be used to reduce noise in ship engine rooms. This study contributes to the development of natural fiber-based insulation materials in the maritime industry.

Study of the Effect Launching System using Airbags on the Hull Structures of Pinisi Ship

Using airbags for ship launching is a technological innovation with promising implications for the shipbuilding industry. Considering the inefficiency and time consumption of the traditional Pinisi ship launching method, an airbags system is considered an alternative technology. This research involves a simulation of applying airbag technology for ship launch on the Pinisi Ship to assess stress concentration and magnitude. The Pinisi ship, airbags, and skates are designed in three dimensions on a real-size scale for analysis and then analysed using Finite Element Analysis (FEA) in ANSYS software. During the launch, the keel of the ship and airbags were subjected to a compressive force with a 3-millisecond analysis time. The stress and stress concentration levels in the Pinisi ship's structure vary between using airbags and the traditional launch method during launch. The ship's engine room bulkhead and the bow collision bulkhead structure underwent considerable tensile and compressive stresses in longitudinal and transverse orientations. The average maximum compressive stress and maximum tensile stress that occur in the longitudinal direction of the ship are around 50.2 MPa and 87.3 MPa, respectively. Compared to the maximum compressive stress, which accounts for 36% of the overall maximum stress encountered, the highest tensile stress experienced by the ship's structure is 64%.

Method for Collaborative Layout Optimization of Ship Equipment and Pipe Based on Improved Multi-Agent Reinforcement Learning and Artificial Fish Swarm Algorithm

The engine room is the core area of a ship, critical to its operation, safety, and efficiency. Currently, many researchers merely address the ship engine room layout design (SERLD) problem using optimization algorithms and independent layout strategies. However, the engine room environment is complex, involving two significantly different challenges: equipment layout and pipe layout. Traditional methods fail to achieve optimal collaborative layout objectives. To address this research gap, this paper proposes a collaborative layout method that combines improved reinforcement learning and heuristic algorithms. For equipment layout, the engine room space is first discretized into a grid, and a Markov decision process (MDP) framework suitable for equipment layout is proposed, including state space, action space, and reward mechanisms suitable for equipment layout. An improved adaptive guided multi-agent Q-learning (AGMAQL) algorithm is employed to train the layout model in a centralized manner, with enhancements made to the agent’s exploration state, exploration action, and learning strategy. For pipe layout, this paper proposes an improved adaptive trajectory artificial fish swarm algorithm (ATAFSA). This algorithm incorporates a hybrid encoding method, adaptive strategy, scouting strategy, and parallel optimization strategy, resulting in enhanced stability, accuracy, and problem adaptability. Subsequently, by comprehensively considering layout objectives and engine room attributes, a collaborative layout method incorporating hierarchical and adaptive weight strategies is proposed. This method optimizes in phases according to the layout objectives and priorities of different stages, achieving multi-level optimal layouts and providing designers with various reference schemes with different focuses. Finally, based on a typical real-world engine room engineering case, various leading algorithms and strategies are tested and compared. The results show that the proposed AGMAQL-ATAFSA (AGMAQL-ATA) exhibits robustness, efficiency, and engineering practicality. Compared to previous research methods and algorithms, the final layout quality improved overall: equipment layout effectiveness increased by over 4.0%, pipe optimization efficiency improved by over 40.4%, and collaborative layout effectiveness enhanced by over 2.2%.

An investigation of the effect of workload on ship engine room operators using fNIRS

This is an investigation into the Performance Shaping Factors (PSFs) associated with ship engine room operators. This study looks at the effect of workload. There is a large portion of human error associated with marine incidents. Human error may be considered as a result of additional supplementary tasks on top of an accustomed workload. The aim of this study is to evaluate the effect of workload on human performance. To achieve this, a TRANSAS simulator series 5000 was used to replicate a real scenario with the addition of workload as a PSF. Each participant engaged in a fault detection and correction task. 20 participants were used for the workload study; all 20 were trained for 3 h to use the engine room software interface. The participants then completed a 30-min ballasting task. During this interaction, 50% of the participants underwent a simulated scenario where the workload was increased. The other 50% were given a standard task. Functional near-infrared spectroscopy (fNIRS) was used to measure the participant's activation levels, more specifically from the dorsolateral prefrontal cortex (DLPFC) region of the cerebrum. The results showed an increase in activation of the DLPFC during each phase of the task, this trend was magnified by the addition of increased workload. The results are discussed with respect to human performance during varying workload. From the results of this study, a human classification performance model was developed. This model can be used by the maritime industry to better evaluate and understand human error causation.

Perancangan Sistem Pendeteksi Polusi Udara Di Dalam Kamar Mesin Secara Wireless Menggunakan Sensor MQ135 Dan TGS2106 Berbasis Lora Ra-02

Air pollution is a problem that needs attention because it can threaten human life. Many human activities cause air pollution. Especially in closed rooms such as ship engine rooms. Therefore, an air pollution detection tool is needed to determine the air pollution index in that place in order to maintain pollution levels below the threshold value. Therefore, it is necessary to have a tool to detect air pollution using the MQ-135 gas sensor to detect carbon dioxide (CO2) gas and TGS2106 to detect nitrogen dioxide (NO2) gas. The type of research method used is the experimental research method. After designing the tool, testing the tool, the air pollution detection system in the engine room wirelessly using the MQ135 and TGS2106 sensors based on LoRa Ra-02 had an average error rate of 1.3% for the MQ135 sensor reading while the TGS2106 sensor reading had an average level. -average error of 6%. Therefore, the Air Pollution Detection System in the Engine Room Wirelessly Using the MQ135 and TGS2106 Sensors Based on LoRa Ra-02 can work well.

Numerical study on the internal ventilation of the engine room of a ship under construction

Manual welding operations are performed inside the engine room of a liquefied natural gas carrier under construction. The welders are at risk of exposure to welding fumes in case of poor ventilation. Therefore, ventilation fans are installed at shipbuilding sites to improve indoor air quality. Although ensuring the respiratory health of welders is important, studies focusing on ventilation in the ship engine room have not been conducted. Therefore, the ventilation efficiency was evaluated herein based on the placement of ventilation fans to alleviate air stagnation using a computational fluid dynamic (CFD) model operating on Fluent. The mean age of air (MAA) was computed to assess the ventilation efficiency. In addition, particles with size and physical properties similar to welding fumes were sourced assuming 30 welders in the engine room. Results revealed that ventilation fan and/or exhaust in enclosed spaces contributes significantly to alleviating the MAA level. MAA and particle distribution did not correlate well due to the different properties of air and the iron oxide particle. Therefore, to determine the optimal ventilation fan displacement, particle motion should be studied along with performing MAA analysis. The proposed CFD model potentially guides to improvement of the working environments and respiratory health of welders.

Experimental Study on the Hot Surface Ignition Characteristics and a Predictive Model of Marine Diesel in a Ship Engine Room

To ensure the safe protection of marine engine systems, it is necessary to explore the hot surface ignition (HSI) characteristics of marine diesel in ship environments. However, an accurate model describing these complex characteristics is still not available. In this work, a new experimental method is proposed in order to enhance prediction performance by integrating testing data of the characteristics of HSI of marine diesel. The sensitivity of HSI is determined by various factors such as surface parameters, flow state, and the ship’s environment. According to variations in the HSI status of marine diesel in an engine room, the HSI probability is distributed in three phases. It is essential to determine whether the presence of marine diesel or surrounding items can intensify the risk of an initial fire beginning in the engine room. A vapor plume model was developed to describe the relationship between HSI height and initial specific buoyancy flux in vertical space. Further, field distribution revealed significant variation in the increase in temperature between 200 and 300 mm of vertical height, indicating a region of initial HSI. In addition, increasing surface temperature did not result in a significant change in ignition delay time. After reaching a temperature of 773 K, the ignition delay time remained around 0.48 s, regardless of how much the hot surface temperature increased. This study reveals the HSI evolution of marine diesel in a ship engine room and develops data-based predictive models for evaluating the safety of HSI parameters during initial accident assessments. The results show that the goodness of fit of the predictive models reached above 0.964. On the basis of the predicted results, the HSI characteristics of marine diesel in engine rooms could be gleaned by actively determining the parameters of risk.

Experimental and numerical investigations of multi-layered ship engine room bulkhead insulation thermal performance under fire conditions

Abstract The thermal insulation layer of the ship’s engine room bulkhead is typically constructed from multiple layers of mineral wool. This layer is designed to keep the temperature on the surface of the bulkhead below 140°C in case of a fire. However, measuring the inner and external temperatures of each wall panel bulkhead type during a fire can be difficult. To address this issue, this study was conducted to evaluate the multilayer heat transfer capability of the bulkhead insulation in the event of an engine room fire. The study used heat transfer theory, experimental models, and numerical analysis to assess nine bulkhead insulation specimens. These specimens were fabricated from three original specimens and included a 10–30 mm air layer (W-75, W-50, and W-25). The results showed that all improved specimens had better thermal insulation than the originals. Among them, the improved specimens derived from the W-25 specimen exhibited the most significant temperature reduction compared to those derived from the W-75 and W-50 specimens. The results demonstrated a slight difference between the three methodologies, indicating a high level of reliability in the research findings.

Quantitative risk assessment of a spill fire caused by the continuously leaked fuel in a sealed ship engine room

There are a large number of high-temperature heat sources in a ship engine room. Once the oil leakage occurs, it is likely to be ignited and form a spreading and burning spill fire. In this paper, spill fire experiments are conducted in a model-scale ship engine room to investigate their characteristic parameters. The quantitative models of flame height and thermal radiant surface emission power applicable to such fires are verified by the experimental data. Based on that, the classical quantitative risk assessment method is adopted to assess the risk of spill fires using thermal radiation hazard as the main reference, and a detailed framework for quantitative risk assessment of spill fires in ship engine room is established, which includes hazard identification, probability of failure calculation, consequence assessment, and risk quantification. The possible causes of spill fire accidents are briefly analyzed based on the bow-tie model. In cases where thermal threats above the risk threshold for larger leakage rates (70 mL/min), the probability method outperforms the threshold method in terms of accuracy in risk quantification. Additionally, the variation of thermal radiation with combustion diameter is analyzed, and some recommendations for fire emergency rescue are presented.

Bi-AAE: A binary adversarial autoencoder deep neural network model for anomaly detection in system-levels marine diesel engines

Marine diesel engines typically use multivariate time series for health condition monitoring, the anomaly detection of which is fundamental and critical for an entity's operation and management. However, detecting anomalies in multivariate time series remains a grand challenge due to the complex behavior of marine machinery. Therefore, this research proposes a binary adversarial autoencoder model to overcome this issue. The framework is built upon the principles of reconstruction models by fusing Generative Adversarial Networks and Adversarial Autoencoder approaches to analyze the degree of anomaly in multivariate time series. Additionally, it identifies anomalies through a threshold obtained by a statistical distribution-based and unsupervised setting method. To emphasize the model's performance, multivariate condition parameters from actual ship diesel engines are utilized for validation. Two membership functions are recognized as the model metrics to characterize its best performance, evidenced by scores of 0.937 for F1 scores and 0.910 for precision. The proposed strategy can be applied to different types of monitoring systems in the ship's engine room to realize system-level operation and maintenance.

Development and Application of Online Training Teaching Platform for Land-Based Ship Engine Room

Development and Application of Online Training Teaching Platform for Land-Based Ship Engine Room

A Methodology for Ship Cabin Equipment Layout Considering Human Factor Reliability Optimization

_ The paper proposes an innovative methodology of Human Cognitive Reliability- Cognitive Reliability and Error Analysis Method (HCR-CREAM) coupled with A* search and genetic algorithm (GA) to tackle ship cabin equipment layout considering human factor reliability optimization with the goal of minimizing human error probability (HEP) subjected to practical requirements. After establishing the mathematical model of cabin equipment inspection tasks in ship cabin equipment layout problem through HCR-CREAM and equipment geometric simplification, a method of the horizontal movement based on minimum distance is presented to avoid the equipment overlapping, then A* search is used for planning inspection paths and GA with selection, crossover, and mutation operators is applied to solve equipment layout results. A case of equipment layout in a certain ship engine room has been taken to carry out parameter sampling experiments by Latin Hypercube for GA. The results show the solution effect of GA is less affected by its parameter variation. And through the comparison with the initial equipment layout, the indicators influencing the HEP of the optimized result have been improved, thus significantly reducing HEP. Keywords ship cabin equipment layout; human factor reliability optimization; HCRCREAM; A* search; genetic algorithm

Research on gas diffusion and explosion characteristics in a ship engine room

This study focuses on potential gas leakage scenarios during the natural gas transportation process in ship engine room. A three-dimensional model of the ship engine room is constructed to investigate the diffusion patterns of leaked gas and the resulting explosion and disaster risks. The results reveal that natural gas exhibits the highest concentration along the jet direction, with the concentration remaining above 5% by 360 s after the leakage. When an explosion intensity of 5 is chosen, the calculated results from TNO multi-energy method show an average relative error of less than 10% compared to the numerical simulations beyond 20 m. In the rear of obstacles, the peak overpressure decreases by 60%, and the time to reach the peak overpressure extends to 1.8 times the original duration. The range of slight building damage caused by explosion overpressure is the largest, averaging about twice the range of minor injuries to personnel.

Influence of Edge-Limited Hot Surfaces on Accidental Ignition and Combustion in Ship Engine Rooms: A Case Study of Marine Diesel Leakage

To extend initial ignition-related fire prevention in ship engine room, this work presents a case study of marine diesel leakage for identifying accidental ignition by hot surface. Based on a self-designed experimental platform, a full-scale innovative experimental arrangement was conducted for diesel leakage-related hot surface ignition (HSI) tests in a ship engine room. A series of parameters (e.g., heat transfer, evaporation mode, ignition position, ignition delay time, flame instability, and combustion behavior) for improving the initial HSI of diesel leakage on an edge-limited hot surface were analyzed. A transient sequence corresponding to a change in leakage flow rates ranging from 7.5 mL to 25 mL was tested, and hot surface temperatures (HSTs) were adjusted between 390 °C to 525 °C. Puffing motion accelerated the mixing of HSI-driven vapors with fresh air, which was affected by the edge-based limitation and HSTs. The case study identified the effects of hot surface shape and the most important combinations of HSI-driven combustion characteristics for estimating initial ignition responses. Based on this current work, prediction models were proposed for determining the HSI height of marine diesel for varying leakage flow rates and HSTs. The results indicate that HSI height increases with leakage flow rate and HSI position is influenced by edged hot surfaces, leading the vertical centerline to shift towards the side of the edge structure. The results also revealed that the ignition delay time of diesel leaked onto an edged hot surface decreases as leakage flow rate increases. This change causes the initial HSI to occur earlier, potentially creating an extra risk in ship engine rooms.

Exploring the effects of automation malfunction on team communication and coordination in ships' engine rooms

AbstractAutomation malfunctions within complex socio‐technical systems reserve the potential to significantly affect human performance. In the context of maritime operations, varying consequences of automation malfunction on human performance can be observed. This study introduced a two‐step research framework to examine the repercussions of such malfunctions, particularly those related to communication and coordination among human teams in ship engine rooms. Initially, a qualitative semi‐structured interview was conducted with seven professional marine engineers to explore the potential impact of hypothetical automation malfunction on team communication. Subsequently, a quantitative survey involving 32 professional marine engineers employed coordination demand analysis (CDA) to scrutinize changes in team coordination resulting from malfunction. The findings indicate that an automation malfunction within an engine room can precipitate an abrupt overload of the socio‐technical system. This can significantly increase communication frequency among engineers, particularly in relation to the physical and organizational aspects of the environment. Furthermore, the study highlights the influence of disparate levels of expertise among team members on coordination demands. A positive correlation was discovered between differences in expertise and increased coordination demands within a team. These insights underscore the necessity for future research on human–automation interaction, specifically focusing on individual differences and nontechnical skills.

Experimental study on the effect of sloping substrate on the spill fire in a well-confined ship engine room

Fuel leakage in the ship engine room tends to form the dynamically evolving spill fires instead of pool fires, which are full of danger and have been scarcely concerned. In this work, one-dimensional spill fire experiments with different fuel leakage rates and substrate slopes are tentatively conducted in a well-confined model-scale ship engine room to reveal their fire dynamics characteristics. It is found that the development of spill fires in the ship engine room is quite different from that in open space, and it, to a great extent, depends on the specific leakage rate and substrate slope. Typically, the spill fire in the ship engine room can be divided into five stages: continuous spreading, steady burning, burning shrinkage, quasi-steady burning, and decay stages, while the steady or quasi-steady stage does not always appear for all cases. In the quasi-steady burning stage, the thickness of the critical oil film is between 0.97 and 1.55 mm, smaller than that in the open space. The special fire phenomena are mainly attributed to the confined boundary condition, where the competing mechanisms of fuel control and ventilation control effects will collectively influence the development of the spill fire in the ship engine room. Characteristic parameters of spill fires in ship engine room, including flame spread rate, burning area, burning rate, and flame height, are also quantitatively analyzed.

STUDY ON THE INFLUENCE OF MULTI-FREQUENCY NOISE ON THE COMBUSTION CHARACTERISTICS OF POOL FIRES IN SHIP ENGINE ROOMS

A large amount of low- and medium-frequency noise can be found in the engine room of a ship. However, during the development of a fire, vibrations of the air in the engine room at different frequencies can be caused by noise disturbances, and the flow field distribution in the flame zone will be changed, which will affect the combustion characteristics of the pool fire. In this paper, an n-heptane pool with a diameter of 6 cm in a confined space of 1500 mm × 1500 mm × 1000 mm is used. The effects of noise of 75 dB, 90 dB, 105 dB, and 112 dB at 250 Hz, 700 Hz, and 1000 Hz and the noise of the engine room on the combustion behavior of the pool fire are studied experimentally. The results of the analysis of the variation in fuel mass, flame height, and flame tilt show that the multi-frequency noise significantly affects the combustion characteristics of the pool fire in a confined space. Under the perturbation of noise waves, the fuel mass flux of the pool is larger than that of the pool fire when it burns freely, and the fuel mass flux is exponentially nonlinearly related to the noise pressure. In general, the flame height gradually decreases with an increasing noise pressure in the engine room. Additionally, a new coupling relationship between the flame height and the noise pressure is established based on the noise motion equation, and it is found that there is a negative exponential between the noise pressure and the flame height. In addition, the flame can tilt under the action of the air particle displacement caused by the noise of the engine room. The noise pressure field formed in the confined space has a restraining effect on the pool fire, and the flame tilt angle gradually decreases with an increasing noise pressure.

INFLUENCE OF VIBRATION ENVIRONMENT OF SHIP ENGINE ROOM ON COMBUSTION CHARACTERISTICS OF SMALL-SCALE POOL FIRES

The vibration environment generated by various operating equipment in ship engine room can significantly affect the heat transfer and combustion characteristics of pool fires. In this paper, with n-heptane as fuel, the combustion characteristics and heat transfer characteristics of pool fire under vibration frequencies of 0 Hz, 3 Hz, 5 Hz, 7 Hz, 8 Hz, and 9 Hz are studied for pool with diameters of 6 cm, 10 cm, 15 cm, and 20 cm. By comparatively analyzing the changes in quality change, flame geometry shape, temperature field and heat transfer characteristics, it is found that the vibration environment changes the typical evolution characteristics of pool fire combustion. The high vibration frequency (> 3 Hz) changes the typical development characteristics of the pool fire in the static environment, and its stable combustion phase disappears. Except in precombustion phase, the mass burning rates increase as the vibration frequency increases. The flame height is positively correlated with the vibration frequency. Additionally, the Heskestad model of flame height is developed, and coupling relationships between flame height and heat release rate, pool diameter and vibration frequency are established. At the same time, a vibration correction factor is proposed, and the heat transfer model is developed.