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Lubrication System is a system that serves to lubricate moving objects in the engine to reduce friction so that when operated the engine does not overheat and does not wear out quickly. One of the problems occurs in lubricating oil pressure resulting in not optimal engine lubrication so that it will affect engine performance. Good pump performance will make the lubricating oil circulation pressure stable and can lubricate the engine optimally. The purpose of this study is to determine how the main engine lubrication performance mechanism and the importance of maintaining the quality of maintenance. which is viewed from the perceptions and expectations of the crew and knowing the factors that affect the operational expectations of the ship's engine. This research refers to the theory of maintenance quality which includes meaningful, responsibility, democratictly, and maintenance. The output of this research is to obtain the value of perceptions and expectations of crew and ship engine operations on the performance mechanism of the main engine injector and the importance of maintaining the quality of maintenance. The research method used in the research is a qualitative method using a descriptive approach to data analysis techniques. The research data sources were obtained from primary data and secondary data. Data collection techniques through observation, literature study, documentation, and interviews during the author's research at KMP. Merak. The results of the research, can be known the problems caused by the temperature and pressure of the lubricating oil system and complete the solution carried out so that the temperature and pressure of the lubricating oil system remains optimal in the KMP main engine. Merak. [ABSTRACT FROM AUTHOR]

The main engine serves as the primary power source for propelling the ship forward and backward. This engine operates on an internal combustion system, where fuel and air are compressed in the combustion chamber to generate thermal energy, which is then converted into mechanical energy through piston movement. This study employs a qualitative descriptive method with SHEL data analysis techniques, identifying the causative factors, impacts, and corrective measures associated with the non-rotation of the valve rotator in the main engine. The findings indicate that the primary cause of the valve rotator's non-rotation is improper installation of the valve collet and wear on the valve rotator body, which affects valve performance and reduces the overall efficiency of the main engine. Corrective actions include replacing the valve rotator and performing routine lubrication checks to prevent further damage.

Turbocharger fouling phenomenon was analyzed from the risk assessment perspective in this study. The research employed exhaust system and turbocharger equipment of commercial ship that equipped with a Doosan-MAN B&W 6S50 MC-C diesel engine was used as the main research materials, and utilized the fuzzy Failure Mode and Effects Analysis (FMEA) based on the expert system as a methodical approach. The experts revealed different types of turbocharger fouling failure modes (FMs), along with their respective causes and subsequent consequences. Following that, the specialists allocated an O, S, and D score to each FM. Within the framework of fuzzy logic, the process entails the establishment of input and output membership functions, as well as the construction of a fuzzy model incorporating an inference mechanism and a rule base. Based on the analysis findings, the three primary factors are as follows: low cylinder compression pressure with a Fuzzy Risk Priority Number (FRPN) score of 6.95, high main engine fuel oil consumption with a score of 6.92, and high CO, CO2, SOx emissions with a 6.45. The phenomenon of turbocharger fouling, being an inherent occurrence, has significant ramifications on the main engine, the vessel as a whole, and the ecological surroundings. The quantitative results presented in this study provide valuable insights into the risks associated with maritime endeavors. The data generated from this research can be used by stakeholders in the maritime industry to better understand this situation and take proactive measures to mitigate potential risks in the future. Furthermore, the findings of the research provide corroboration for the implementation of predictive maintenance procedures. [ABSTRACT FROM AUTHOR]

Lubrication is one aspect that must be paid attention to, remembering that if there is a delay in lubrication or imperfect lubrication, it will result in damage to the parts that rub together. Low lubricating oil pressure is one of the factors causing imperfect lubrication in the engine. The purpose of lubrication for the performance of the main engine is to reduce friction between other components of the main engine. This research was carried out at MV. Manalagi Dasa, the method used in this research was the Fishbone Diagram. The problem formulation of this research is what causes an increase in the temperature of the lubricating oil on the main motor and what is the impact of increasing the temperature of the lubricating oil on the main motor. Based on research that has been carried out, there are several factors that cause less than optimal lubrication of the oil cooler on the main engine, namely engine factors including damage to gaskets, human factors, namely the lack of understanding of the driver about the lo cooler, operational and maintenance method factors, namely incompatibility in implementing the PMS (Plan Maintenance System) as well as environmental factors, namely dirty sea chest filters. Efforts made include repairing or replacing gaskets on the lo cooler plate, the importance of the machinist's understanding of the lo cooler, implementing PMS (Plan Maintenance System), and cleaning the sea chest filter.

A body flap is usually arranged on the base of the plane-symmetry reusable launch vehicle with the longest moment arm for the need of pitch balancing control. Jet interaction from main engine with body flaps is an important problem that cannot be ignored in the design of reusable launch vehicles, which would cause severe regional heating of the flaps and increase technical difficulty of thermal protection design. In this paper, the high temperature jet interaction with the body flaps was studied in a combustion gas flow wind tunnel experiment, and jet heating characteristics of direct acting and secondary interference were obtained and analyzed. Then, numerical simulations on the complex jet interaction flow field for typical flight conditions were carried out using a multi-species frozen model which is verified by the experiment data. Finally, correlation analyses of heat flux and flow field characteristics both for the jet direct acting and secondary interfe-rence were performed, by which the jet heating main controlling factors and correlations were obtained for two different interference types. Such method is very effective to realize a fast and accurate jet heating prediction for a reusable launch vehicle.

Under the recent background of ‘Green Shipping’ and rising fuel prices, it is very important to reduce the fuel consumption rate of ships, which is directly affected by the performance of the main engine. A reasonable maintenance schedule can optimise the performance of the main engine. However, a traditional maintenance schedule is based on the navigation distance and time, ignoring many other factors, such as a harsh working environments and frequently changing operating conditions, which will lead to faster performance degradation. In this study, a real-time evaluation method combing big data of ship energy efficiency with physics-based analysis is proposed to judge the degradation of main engine performance and assist in determining the maintenance schedule. Firstly, based on the developed ship energy efficiency big data platform, the distribution statistics and comparison of different operating states are carried out. Gaussian mixture model (GMM) and Density-Based Spatial Clustering of Applications with Noise (DBSCAN) are used to cluster the data and the high-density data areas are obtained as the analysis points. Then, the data of the analysis points are polynomial fitted, by the least square method, to obtain the propulsion characteristics curves, load characteristic curves, and speed characteristic curves, which can be used to observe the performance degradation of the main engine. The results show that this method can effectively monitor the degradation degree of the main engine performance, and is of great significance to fuel efficiency improvements and greenhouse gas (GHG) emissions reduction.

This article presents the influence of various ship’s operational conditions occurring during manoeuvres related to entering and leaving the ports and mooring operations. Frequent starts and stops of the ship’s propulsion unit are then required, which affect the variability of the energetic loads of the ship’s power plant, causing accelerated, non-design wear of the ship’s main propulsion engine. The effects of cold start-ups of the main ship engine are the subject of this study. Conditions of the engine inlet valve damage process are discussed. The physics of the degradation process leading to air inlet valve damage was considered. Laboratory tests of structure continuity and their results are discussed, and the valve material defects were excluded as the cause of the damage. The causes of repeated damage to the inlet air valves were identified. The effectiveness of the performed corrective measures was confirmed by a documented control test of the engine start-up. The article is a utilitarian premise for the requirements of the Classification Society.

The purpose-oriented design and planning of ships is maintained throughout production. Outer form of ship equipment starts with the steel construction process. The outer body production process moves ahead with painting, quality control tests, and bureaucratic procedures. In accordance with all these form and block operations, choosing a main engine suitable for all other technical parameters is vital, especially regarding ship speed and the amount of cargo it will carry. As a result, estimating main engine power is attempted with the help of artificial neural network (ANN) and regression analyses by considering a ship's technical parameters (e.g., draught, depth, deadweight tonnage [DWT], gross tonnage [GT], and engine power). This study conducts regression and ANN analyses over 836 tanker ships from the Marine Traffic database to predict main engine power using input parameters (deadweight (DWT), Length (L), Breadth (B), and gross ton (GT) values). The regression analyses show Model 7 to perform the best approximation with a determination value = 0.827 usable for estimating main engine power. After all the examinations, a very accomplished result of 0.98047 was additionally obtained from the ANN analysis. The study makes beneficial and innovative contributions to predicting tankers' required main engine power. [ABSTRACT FROM AUTHOR]

Maintenance of the Fishing vessel's main engine by a risk assessment of critical components in the system is a crucial factor for operating fishing vessels. This article analyzes the main engine's risk level using the fuzzy-FMEA model. The system components and their failure modes were obtained by direct observation of eight fishing vessels in Batam, Indonesia. The evaluation resulted in a ranking of critical components in a row using C-RPN analysis, namely the injector (200.61), injection pump (159.94), and fuel filter (95.09). In comparison, the F-RPN analysis resulted in changes in the values of the critical components, respectively, namely the injector (454.80), injection pump (358.42), and fuel tank (293.48). The F-RPN value in the investigated analysis is more accurate because in evaluating the data entered, the risk parameter index of the evaluation results. The fuzzy-FMEA model has the advantage of accurately assessing the level of component failure risk on the main engine of fishing vessels because it has accuracy in getting the value of potential risk on C-FMEA in entering risk parameter indicator data. Fuzzy-FMEA model contributes to the existing knowledge of maintenance planning by using risk analysis on critical components of the main engine of fishing vessels. [ABSTRACT FROM AUTHOR]

The scientific aim of this paper is to analyse the topicality of the turbocharger explosions and to attempt to answer the question of whether some technical characteristics of the engine can be perceived as directly connected with the risk of the turbocharger explosion. Moreover, our objective was also to calculate the turbocharger explosion probability. This article presents the results of a quantitative and qualitative analysis of 42 explosions of marine main engine turbochargers occurring between 1977 and 2022. The number of explosions was analysed, and the average and instantaneous frequencies of turbocharger explosions each year were determined. An analysis was performed of the number of explosions with respect to the age and type of ship on which the accident occurred. An analysis of the contribution of different types of main engine to the studied population of explosions was also carried out. Criteria such as the number of strokes, engine speed, type of crank-piston mechanism, cylinder arrangement, engine power per cylinder, and number of cylinders were considered. An analysis was carried out of the disasters that had occurred, considering the contribution of the various engine manufacturers. An integrated distribution of the number of turbocharger explosions by year was presented, considering the engine speed, the maximum continuous rating of the engine, and the engine design. The analysis did not indicate a significant correlation between the type of ship and the number of explosions that occurred. More than half of the analysed population of explosions (median) occurred on vessels no older than 15 years. It is highly likely that engine type does not directly affect the number of turbocharger explosions and the risk of explosions. On the other hand, it is not possible to exclude the influence of the individual characteristics of an engine built to a particular manufacturer's design on the magnitude of the risk of a turbocharger exploding during engine operation. Considering the number of ships worldwide, the probability of an explosion in a given year on a given ship is not less than 1.61 × 10−7. [ABSTRACT FROM AUTHOR]

Inherited volatility and the vulnerability to economic conditions make shipping a challenging business. The prices of second-hand ships and newbuilding are strongly interrelated and are affected by market dynamics. Therefore, understanding factors affecting second-hand prices of ships can be crucial for countries specialize in shipbuilding to diversify their international trade participation via vessels' exports. This study provides a framework for evaluating several influential factors on second-hand ship prices in different market segments and contributes with managerial implications supporting the shipbuilding industry from a strategic, operational and marketing perspective. This study uses an ordinary least square regression considering a total of 8948 sales transactions of second-hand vessel sales from 2008 to 2020 to determine the effect of factors as age, size and the freight on second-hand ship value. Furthermore, it investigates the effect of ships sold under a time charter agreement, country of built and the type of main engine. The findings suggest that the ships' type of main engine and the country of build are statistically significant among most vessel categories, while other vessel-specific and economic factors also explain the value of second-hand ships consistent with the literature. Furthermore, the behaviour of the multivariate model is unique depending upon the type of ship classification, which hinders the possibility of generalization. Several implications for the shipbuilding industry are finally derived. The study contributes to existing literature by extending both the factors and type of ships (17 categories among, bulk, tankers and containers) considered in the analysis. [ABSTRACT FROM AUTHOR]

This article aims to compile, describe and compare three different models taken from the literature describing the causes of explosions in the crankcases of marine engines. Each of the models has a different level of detail and was prepared with a different purpose. However, the same process, explosions in crankcases, was analyzed in all cases. A statistical evaluation of the frequency of events leading to explosions, a model built using failure mode and effects analysis (FMEA) and a model based on fault tree analysis (FTA) are described in turn. The FTA model drawn from the literature formed the basis for further analysis. Values of important measures of all elementary events of the fault tree were calculated using the Birnbaum reliability measure, Vesely-Fussell measure, Birnbaum structural measure, criticality measure and improvement potential. The percentage importance values of all events determined using these importance measures were compared. The results obtained from the application of each model were evaluated. The results of the models were compared with each other, and an approach using all three models supplemented with diversion analysis was proposed. [ABSTRACT FROM AUTHOR]

Transportation is one of the supporting factors for the smooth running of the economy in a country. One of the transportation is sea transportation because it is more effective and efficient. For this reason, the ship which is the main factor in the smooth operation of sea transportation must be prepared in its operation, the main thing that can support the smooth running of a ship is the smooth operation of the main engine. In general, the main engine on board the ship uses a diesel engine type, and the starting system uses compressed air where the compressed air is produced by the compressor auxiliary aircraft, so it can be said that the compressor has an important role in the operation of the ship. The compressor is one of the aircraft that is used to compress low-pressure air with higher pressure. During the operation of the main engine when the motion occurs, sometimes there are obstacles or obstacles that cause damage to the air compressor, so the compressor cannot work optimally. This results in the process of filling the main engine starting water for too long and can affect the smooth process of movement. The purpose of this study is to find out the obstacles or obstacles that can interfere with the main engine of the composer. The method used by the author in this study uses descriptive qualitative with several methods, namely, approach methods and data collection techniques. In the discussion in this study the author by finding several solutions to problems carrying out maintenance on engine room blowers and routines on the compressor as well as cleaning rust on the plunger and parts of the auto drain solenoid valve. The conclusions obtained in this study must maintain the air temperature in the engine room and always clean the high-pressure valve and low-pressure valve and pay attention to the compressor temperature so it doesn't get too hot because it can produce worse air. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present the results of a query aimed at assessing the validity of the topic of crankcase explosions prevention in the main marine engines. The study takes into account the engine type, engine manufacturer, ship's age, accident severity, ship's location at the time of the incident, and the share of fatal accidents in the analyzed population of crankcase explosions. One of the primary hazards associated with offshore and deep-sea ship operations - and primarily ship power plants - are fires and explosions that result in accidents and incidents with an average frequency of 60 days. This paper discusses the actuality of crankcase explosion hazards in the main propulsion engines of various types of sea vessels. The assessment was made based on the results of a statistical analysis of historical data from 1972 to 2018. The methodology consisted of three stages: (1) a selection query to obtain the source data, (2) analysis of the obtained results (data separation, extraction of additional information, and statistical analysis), (3) synthesis of the obtained information, and drawing conclusions about the numerical indicators describing the statistical distribution of individual events for the given evaluation criteria. The analysis showed that the risk of crankcase explosions affects ships of all ages - both in crosshead (31%) and trunk piston engines (61%) - and that the number of serious incidents (67%) remained constant over the investigated period. Half of all incidents occurred on vessels younger than 15 years old. 58% of explosions took place in engines of the most popular prime movers manufacturers. The probability that a main engine crankcase explosion will result in injury or death is 17.34%. [ABSTRACT FROM AUTHOR]

Today huge capacity sea-going vessels are propelled by mega high-powered marine diesel ‎engines, referred to as Main Engine. Turbocharging system is an integral part of large marine diesel engine plant, ‎contributing to their safety, reliability, and efficiency. Defects in the turbocharging system ‎could result in higher fuel consumption, erratic running of the Main Engine, and in the worst ‎scenario may result in the stoppage of the Main Engine at sea. An inefficient turbocharging system may also cause major damage to turbochargers, resulting in undesirable accidents out at sea. To ‎avoid such undesirable accidents and ensure smooth operations of the Main Engine, it is required to ‎address this concern. The aim of this research is to study the turbocharging system for a ‎large Main Engine using a Kongsberg engine ‎simulator. Various malfunction of the ‎Turbocharging system is considered, relevant data is collected and analysed. ‎Moreover, a Fault Tree Analysis, (FTA) is considered to identify the top undesirable event ‎which is the failure of the Main Engine. Based on the results of this study, various steps ‎are suggested to avoid failure of the Main Engine due to the defective turbocharging ‎system.‎

Commercial shipping is currently dominated by mega container vessels. The shipping industry has seen a 10‐fold increase in the size of containers over the last four decades. These vessels are propelled by large marine diesel engines, hereafter referred to as the main engine. The performance of the main engine is determined by its subsystems. An important part of the main engine is the turbocharging system, which contributes to its safety, efficiency, and reliability. In this study, the effectiveness and reliability of the turbocharging system are evaluated. The Australian Maritime College has a Kongsberg Engine Simulator that can produce a variety of malfunctions on a running engine's turbocharging system. Analyzing the results obtained from the simulator determines the efficiency of the turbochargers. The study will provide recommendations for improving the safety of the turbocharging system for better performance to be achieved by the turbochargers, leading to an improvement in the main engine's performance. Last, the reliability of the turbocharging system is evaluated quantitatively using a fault tree analysis and reliability block diagrams. This will enable an optimum maintenance strategy to be established to ensure the safe operation of the vessel. [ABSTRACT FROM AUTHOR]

The scientific aim of this paper is to analyse the topicality of the turbocharger explosions and to attempt to answer the question of whether some technical characteristics of the engine can be perceived as directly connected with the risk of the turbocharger explosion. Moreover, our objective was also to calculate the turbocharger explosion probability. This article presents the results of a quantitative and qualitative analysis of 42 explosions of marine main engine turbochargers occurring between 1977 and 2022. The number of explosions was analysed, and the average and instantaneous frequencies of turbocharger explosions each year were determined. An analysis was performed of the number of explosions with respect to the age and type of ship on which the accident occurred. An analysis of the contribution of different types of main engine to the studied population of explosions was also carried out. Criteria such as the number of strokes, engine speed, type of crank-piston mechanism, cylinder arrangement, engine power per cylinder, and number of cylinders were considered. An analysis was carried out of the disasters that had occurred, considering the contribution of the various engine manufacturers. An integrated distribution of the number of turbocharger explosions by year was presented, considering the engine speed, the maximum continuous rating of the engine, and the engine design. The analysis did not indicate a significant correlation between the type of ship and the number of explosions that occurred. More than half of the analysed population of explosions (median) occurred on vessels no older than 15 years. It is highly likely that engine type does not directly affect the number of turbocharger explosions and the risk of explosions. On the other hand, it is not possible to exclude the influence of the individual characteristics of an engine built to a particular manufacturer’s design on the magnitude of the risk of a turbocharger exploding during engine operation. Considering the number of ships worldwide, the probability of an explosion in a given year on a given ship is not less than 1.61 × 10−7.

In order to reduce the CO2 emission from ships, International Maritime Organization executes the restriction of Energy Efficiency Design Index (EEDI) which limits amount of CO2 when freight of one ton is carried at one mile. Although the realization of higher efficiency of main engine without reduction of engine output is the best solution, it might be impossible. To comply with the EEDI requirements, it is assumed that the ship’s engine power becomes smaller than the existing ship by means of improving the ship propulsive efficiency. However, shiphandling in rough seas is expected to become difficult when the engine power is reduced. In this paper it is shown that the influence of the degraded main engine exerts on the safety of shiphandling in heavy weather based on the simulation study. In these experiments, both the simulation model that decreased engine power corresponding to EEDI requirement and that with the conventional engine power were tested, and masters in active service maneuvered the test ships in the rough seas.

A The novelty of this study consists in the fact that, at the same time as the monitoring and acquisition of data of the air quality (from inside and outside), a monitoring and acquisition of data of the real-time biometric measurements of subjects exposed directly to the needle will be made. Medium by means of a bracelet attached to the subject's arm. This bracelet is designed to perform biometric measurements without creating discomfort to the subjects analyzed in the activities in which they are involved. This measurement is carried out with 9 different sensors for: pulse, oxygen in the blood, air flow (breathing), body temperature, electrocardiogram, galvanic skin response, blood pressure, the patient's position/movement, and the status of muscle (electromyography sensor). The data thus obtained will be focused on a PC and subsequently analyzed. The results of monitoring the health parameters of the subjects analyzed find application in the maritime field, to ships, especially in the engine room, where the air suffers quality transformations. The crew's return to the workplace may decrease due to the degradation of the air quality in the premises.

Maritime transportation is the essence of international economy. Today, around ninety percent of world trade happens by maritime transportation via 50,000 merchant ships. These ships transport various types of cargo and manned by over a million mariners around the world. Majority of these ships are propelled by marine diesel engines, hereafter referred to as main engine, due to its reliability and fuel efficiency. Yet numerous accidents take place due to failure of main engine at sea, the main cause of this being inappropriate maintenance plan. To arrive at an optimal maintenance plan, it is necessary to assess the reliability of the main engine. At present the main engine on board vessels have a Planned Maintenance System (PMS), designed by the ship management companies, considering, advise of the engine manufacturers and/or ship’s chief engineers and masters. Following PMS amounts to carrying out maintenance of a main engine components at specified running hours, without taking into consideration the assessment of the health of the component/s in question. Furthermore, shipping companies have a limited technical ability to record the data properly and use them effectively. In this study, relevant data collected from various sources are analysed to identify the most appropriate failure model representing specific component. The data collected, and model developed will be very useful to assess the reliability of the marine engines and to plan the maintenance activities on-board the ship. This could lead to a decrease in the failure of marine engine, ultimately contributing to the reduction of accidents in the shipping industry.

Safe operation of a merchant vessel is dependent on the reliability of the vessel’s main propulsion engine. Reliability of the main propulsion engine is interdependent on the reliability of several subsystems including lubricating oil system, fuel oil system, cooling water system and scavenge air system. Turbochargers form part of the scavenge sub system and play a vital role in the operation of the main engine. Failure of turbochargers can lead to disastrous consequences and immobilisation of the main engine. Hence due consideration need to be given to the reliability assessment of the scavenge system while assessing the reliability of the main engine. This paper presents integration of Markov model (for constant failure components) and Weibull failure model (for wearing out components) to estimate the reliability of the main propulsion engine. This integrated model will provide more realistic and practical analysis. It will serve as a useful tool to estimate the reliability of the vessel’s main propulsion engine and make efficient and effective maintenance decisions. A case study of turbocharger failure and its impact on the main engine is also discussed.

This article shows the importance of the diagnostic improvement methods of marine engines to boost the economy and safety of operation of marine cargo ships. The need to implement effective diagnostic methods is justified by presenting statistical data of marine diesel engines failure and the cost of their operation. Based on the own research has been proven, for the chosen example, that indicator diagrams and analysis of indicated parameters have limited utility in the diagnosis of damages of marine engine, although this is a method commonly used in operational practice. To achieve greater diagnostic effectiveness, when, based on indicator diagrams, are calculated and then the characteristics of heat release is analyzed - net of heat release characteristics and the intensity of the heat release, it was demonstrated. This procedure is particularly effective in the diagnosis of damage of injection system components marine diesel engine.

In terms of electric ship energy requirement in navigation, the ship charging station location is especially important. In this paper, a multi-period ship charging station location optimization model is pro-posed to make location decision in overall, from initial possible station sites chosen to the capacity determination for the final location sites. In the first phase, from the perspective of external environment, find out all possible ship charging station candidate sites through the feasible analyze. In the second phase, taking the ship charging demands into consideration, the final ship charging station sites can be selected among the candidate sites based on backup coverage model. In the last phase, regarding the cost of construction and service capability for different grade as the main factor in capacity determination, the optimal capacity of each final ship charging station are determined by means of optimization method. Finally, an example of Yanqi lake in China is used to verify the validity of the proposed methodology. The reasonable location of charging station could ensure the electric energy supply and avoid congestion caused by ship charging gathering. The model can be easily generalized to other problems regarding facility allocation based on user demand.

Summary: Ballast water management is a national and international issue in the shipping industry because of potential ecological hazards caused by the release of ballast water into the marine environment. Although many international standards have been implemented in recent years, technological and practical considerations make the ballast water treatment a major challenge for many shipping companies. In this paper, a novel concept of utilizing ballast water as source water for a multieffect desalination process driven by onboard waste heat to meet the freshwater supply needs is proposed with theoretical analysis and practical considerations. A main engine with a capacity of 7500 kW in a cruise ship can serve as a potential waste heat source for water desalination of 1000 m3/d, which can provide for freshwater needs of 2000 to 4000 ship occupants. This scenario presents an attractive alternative to ballast water management and treatment as well as reducing the nonrenewable energy footprint of onboard water supplies in marine industry. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the magnitude of the performance correlation value of a plunger barrel of high pressure pump (X1) and fuel (Y1) in the main engine injector performance (Y). This study applied SPSS (Statistical Package for the Social Sciences) analysis which produces quantitative data to describe the object under the study. The data were collected through a questionnaire by using a Likert scale approach. The results showed that the X1 coefficient on variable Y was moderate but the correlation value of X2 to Y was low. The correlation value of the influence of variables X1 and X2 together on the variable Y was also low. This variable can be used as an analysis in assessing the performance of the main engine injector in commercial vessels. [ABSTRACT FROM AUTHOR]

This study presents a practical optimization procedure that couples the NavCad power prediction tool and a nonlinear optimizer integrated into the Matlab environment. This developed model aims at selecting a propeller at the engine operating point with minimum fuel consumption for different ship speeds in calm water condition. The procedure takes into account both the efficiency of the propeller and the specific fuel consumption of the engine. It is focused on reducing fuel consumption for the expected operational profile of the ship, contributing to energy efficiency in a complementary way as ship routing does. This model assists the ship and propeller designers in selecting the main parameters of the geometry, the operating point of a fixed-pitch propeller from Wageningen B-series and to define the gearbox ratio by minimizing the fuel consumption of a container ship, rather than only maximizing the propeller efficiency. Optimized results of the performance of several marine propellers with different number of blades working at different cruising speeds are also presented for comparison, while verifying the strength, cavitation and noise issues for each simulated case.