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Biofouling impedes the movement of ships and assists corrosion. The earliest recorded attempts by mariners to prevent fouling date back to the 5th century BC. A major breakthrough in antifouling technology occurred in the 1970s when self-polishing marine paints that continuously released TBT (tributyl tin) revolutionised the ship-coating industry and allowed longer intervals between dry-docking. However marine technologists now have to identify new coating techniques that will survive the forthcoming more difficult regulatory environment. To address this issue research was carried out to evaluate the feasibility of incorporating nanocomposite materials in marine coatings. This paper reports on the preliminary empirical findings. Since the last decade numerous studies have been carried out to investigate the mechanical thermal and electrical properties of polymers mixed with nanoparticles. However the dispersion properties which govern the integrity and structural properties of the composites is a critical issue (due to the clustering effect and agglomeration). In this study a new experimental setup and procedure was developed to produce uniformly dispersed nanoclay or epoxy composites. The preliminary findings showed that small and uniformly sized nanoclay clusters were formed and the hardness of composites can be increased by as much as 50 per cent through the presence of 4 wt.percentage of nanoclay.

In the present competitive market undertaking a ship mission on schedule and on time is important. Predicting increased resistance of a ship to her governing wave climate is therefore important. At present there are several methods available for dealing with the problem of resistance increase in waves. Most of these methods are based on the calculation of motion responses by Strip Theory or Slender Ship Theory. Although these methods are easy to use and produce acceptable results some of their shortcomings (due to the neglect of 3D hydrodynamic effect) make them unable to provide enough estimation of the increase of resistance in waves especially for fuller ship form vessels. The 3D Green function method with forward speed is now able to estimate better all relevant hydrodynamic responses and is therefore becoming increasingly popular. Linear potential theory is used to describe the fluid motion. The 3D sink-source technique with forward speed is applied to determine hydrodynamic forces for surface ship advancing in waves at constant speed. After solving the motion equation in frequency domain radiation potential due to motion responses is calculated to obtain the total potential of the flow field. Then total potential and its derivatives are obtained to assess the added resistance in waves by near field approach. To show the validity of the numerical code the present numerical results for motion responses and wave loads on ships are compared with experimental data as well as with some numerical results achieved by different approaches. Next the added resistances given by present numerical calculation byX38576 A numerical analysis on the deformation of decomposed granite soil foundation using elasto-plastic model

Fourth Int Symp held in Houston 25 - 28 April 1979 Papers are The US merchant marine - future in forecast Elastic foundation of deckhouses Minimum freeboard requirement for dry foredecks - a design procedure Capsize safety Cavitation erosion prevention by air injection An overview of current and proposed tank vessel safety and pollution measures A statistical and economic evaluation of stern tube bearing and seal failures The effect of hull proportions on IMCO tanker segregated ballast requirements A gas turbine electric propulsion system for an LNG carrier A preliminary assessment of the demand for reception facilities stemming from the implementation of MARPOL 1973 Future development of the slow speed diesel engine Naval ship design - past present and future Training of ship operators - the marriage of theoretical and practical education Improving the fuel efficiency of navy 8300 (1200 psi) steam plants An at - sea comparative analysis of deck performance with and without automated information displays A comparative analysis of naval auxiliary and merchant ship design Simulator training for improved shiphandling skills Low friction propulsion by means of boundary layer control Paravene roll stabilisation The United States nuclear merchant ship programme - financial protection issues in the operations of nuclear merchant ships The estimation of ship motion induced forces A practical guide for determining the vibration characteristics of plate structures

Modern ships particularly container and fuel carrying vessels are becoming increasingly automated. This automation has brought with it two problems. The first problem concerns the inadequacy of existing seafarers' education and training - that is if any aspects of automation fail the crew are often not trained to use alternative systems. The second problem has arisen from the review of the arguments in recent IMO Maritime Safety Committee reports namely that the human operators rarely understand all the characteristics of automatic systems and these systems' weaknesses and limitations which have now been found to be one of the main causes of major accidents. Also concerns were expressed about the English language competency of seafarers of various ranks. These reports concluded that there is a need to improve the content of all maritime training to include knowledge skills and understanding of automation and that teaching of English in maritime institutions should be improved. Several serious and recent accidents at sea are referred to which are due to automation failure and reports as to how serious attempts could be made to address both problems identified and improve the situation regarding the teaching of English in maritime institutions.

Ship inspections help gauge the status of a vessel for various applications. There are a variety of inspections with a wide range of expertise. Some inspections are commercially initiated many are iterative and most are regulatory. IMO has taken a very proactive approach to this issue. It is now involved firstly in providing a forum where parties whose members are involved in ship inspections and surveys can present their current practices and offer their individual and collective views on how to deal with the problems caused by the excessive number of inspections to ships when in port or at offshore terminals. Another purpose is to agree that for safety and environmental protection reasons it is desirable to alleviate the workload imposed on shipmasters and officers through a reduction in the number and scope of onboard inspections while in port. A further purpose is to agree on a collective course of action to remedy the situation. Lately a number of standardisation processes and methods have been introduced into the maritime inspection regime. The emphasis is now slowly changing to an audit inspections regime and therefore increasing the reliability of systems components and equipment preventative maintenance and risk-based formal assessment schemes. In the near future it is hoped that digitalisation of such inspection findings will lead to safety indexing as normal practice. The inspection methodologies are discussed briefly and a few contemporary approaches are suggested to obviate contradictions.

The USCG (Coast Guard) is currently complying with the International Convention for Prevention of Pollution from Ships (Marpol 73-78) Annex 5. The CG carefully evaluated the needs of its major cutters the equipment market search and an EA (environmental assessment) of the proposed alternatives before choosing marine incinerators as the primary alternative for safe disposal of solid and plastic waste onboard its major cutters. The type of marine incinerator chosen not only handles solid and plastic waste but can also burn waste oil and oily waste thus the CG avoids the segregation of plastic from food waste and also saves the cost of disposing of the waste oil. On smaller cutters where an incinerator cannot be retrofitted the CG has opted to install compactors and pulpers to handle the solid waste. The CG's solid and plastic waste management program its status success and recommendations are briefly described. The CG did not follow the Navy's design of solid and plastic waste handling equipment but rather considered the specific needs of its own cutters. The prototype incinerators were installed and tested by the Navy's environmental team and it was determined that they were complying with applicable IMO and US environmental laws and regulations meeting health and safety requirements and supporting the USCG mission.

For larger and faster merchant ships a high-powered main engine should be used. The single propeller is usually chosen for economic reasons. This leads to the propeller power being heavier. Furthermore the power density becomes excessively heavy due to the limitation of diameter of propeller. The increasing possibility of cavitation erosion and the stern vibration must be considered in the propeller design. The design method of a heavy-loading propeller is presented. Firstly several propeller schemes are designed based on the lifting surface theory and then the cavitation-induced forces on hull surface are calculated using Holden's empirical formula. Three better propellers are selected according to the comparison of propeller efficiency and pressure fluctuation. Secondly the open water tests in the towing tank the cavitation observations and the pressure fluctuation measurements in the cavitation tunnel for three propellers above are carried out to obtain the best propeller. Finally the blade strength is checked by the FEM (Finite Element Method) which is based on the pressure distribution calculated by a CFD (Computational Fluid Dynamics) code. The proposed design method was used in the propeller design of a 9000TEU container ship. The results of experiments and calculations show that the final design propeller is of higher efficiency lower vibration and adequate strength.

Marine fuels have changed over the last ten years. Here it is discussed exactly how they have changed the effects on the reliable operation of ships' prime movers how Shell's research and development efforts have increased its understanding of the root causes and the measures that can be taken to reduce the risk of machinery problems or even breakdown to a minimum. The effects of changes to refinery configuration are briefly reviewed. These are necessary to meet the ever-increasing demands for automotive domestic and industrial heating fuels. This has changed the way marine fuels are sourced. A number of real incidents are reviewed where fuels that apparently fully met ISO 8217 specifications have caused significant damage to compression ignition engines or given rise to serious operational problems. The analytical techniques used to identify the root causes of the problems are reviewed - in particular a relatively new technique the FIA for assessing the ignition and combustion characteristics of residual fuels and how based on our R&D activities the data obtained from this technique relates to engine derived data. Finally residual fuel oil stability is discussed i.e. how some proprietary methods of assessing stability can give very misleading results and how in some instances particularly with low sulphur fuels

The earliest example of redundancy in a marine electric propulsion drive is thought to be that of the UK commercial vessel Tynemount in 1913. Of particular note in this seminal design was its ability to provide redundancy and it was this feature which was to become a vital part of innovative design in later generations of variable-speed drives. Most importantly it has subsequently established the idea of electric propulsion as a viable solution to the provision of cost-effective designs in a marine naval market. The ESTD main contract deliverables are a suite of reports and a validated computer model of the installation. An additional task was placed by BAE SYSTEMS to include some Type 45 Destroyer de-risking activities variously called 'Shore Integrated Test' or 'System Integration Trials'. The installation is at full scale and represents a single shaft electric ship complete with a fully functional four-quadrant propeller simulator and a low voltage distribution system that can be operated as AC or DC. There is extensive use of power electronics to control the PM (Propulsion Motor) to generate distribution supplies and to generate the supplies required by consumers. There is also extensive demonstration of the functionality of energy storage both to support consumers in damage control zones of a ship and to support distribution-propulsion on loss of a prime mover. A review of the required technology demonstrations and their hardware implementation isX17245 Experience of automatic control of seagoing cargo ships MER

HVAC equipment plays a crucial role in maintaining a good working environment on board ships. At the same time the system is generally designed with very limited margins due to space and energy limitations. Detecting faults and diagnosing them at an early stage will give substantial benefits both by maintaining a workable environment and reducing energy consumption. The challenge for successful fault detection and especially for fault diagnostics is the knowledge of the faulty system behaviour. A promising way of creating the required knowledge base is by using simulation models to predict faulty behaviour of complex systems. In this paper a mean value principle HVAC system-modelling environment is presented developed based on an RV network concept aimed at enabling faulty behaviour simulation in the design stages of the system. To show the potential the modelling approach was applied to a simple case study for knowledge mining towards fault detection and diagnosis. Two faulty conditions are introduced and analysed under different weather conditions. The results show that the approach has great potential for knowledge mining and thus brings a functional FDD (fault detection and diagnosis) scheme closer to realisation which would help ensure a more secure more efficient and better-controlled indoor environment. More work is needed before FDD can really play an important role in practical applications.

In the context of the GMES (global monitoring for environment and security) and MERSEA (maritime environment and security for the European area) projects the European Union want to set up synthetic indicators for decision makers and environment agencies in order to improve management of environmental risks. One of the major risks of coastal pollution nowadays is hydrocarbon and oil pollution linked to maritime transport. Since 2001 Mercator the French oceanic forecast centre has provided a full 3D forecast of ocean dynamics in real-time. Data produced by Mercator is rich and complex - synthesising such complex information into simple indicators useful for decision makers is a challenge. By using a draft model pollution due to the maritime transport over a period of three years was simulated. Two indicators were created. The first indicator identifies the coasts exposed to maritime traffic pollution and the second shows parts of the ships' routes that lead to significant coastal maritime pollution. The characteristics of the draft model are studied and how ship routes were integrated into the simulation. The creation of the two indicators is assessed. Finally the robustness of tests which justify the indicators' existence is shown.

The original book filled a need for a manual showing the application of theoretical principles to the design and construction of marine machinery, as determined by the experience of leading engineers, and carried out in successful practice. It will help make clearer some of the technicalities of marine design and construction and so help forward the application of scientific investigation to those problems which the marine engineer is called upon, day by day, to solve. This 16th edition is updated to reflect changes in technology. Chapter contents include horse-power - nominal and indicated and the efficiency of engines; resistance of ships and indicated horse-power necessary for speed; space occupied by, and general description of, modern marine machinery; simple and compound engines; expansion of steam, mean pressure etc; piston speed, stroke of picton, revolutions, size of cylinder, cylinder fittings; the piston, piston-rod and connecting-rod; shafting, cranks and crank-shafts; foundations, bed-plates, columns, guides and framing; the condenser; pumps; valve and valve gear; valve diagrams; propellers; sea cocks and valves and auxiliary machinery; boilers, fuel, evaporation; boilers- design and proportions; water-tube boilers; construction and detail of boilers; boil mountings and fittings; fitting in of machinery, starting and reversing of engines; weight and other particulars of machinery relating thereto; weight, inertia, momentum, balancing; materials used by the marine engineer; oil and lubricants.

The original book filled a need for a manual showing the application of theoretical principles to the design and construction of marine machinery, as determined by the experience of leading engineers, and carried out in successful practice. It will help make clearer some of the technicalities of marine design and construction and so help forward the application of scientific investigation to those problems which the marine engineer is called upon, day by day, to solve. This 17th edition is updated to reflect changes in technology. Chapter contents include resistance of ships and indicated horse-power necessary for speed; marine engines - their types and variations of design; steam used expansively; steam used after expansion - turbines; efficiency of marine engines; simple and compound engines; nominal, indicated and shaft or brake horse-power; general design and the influences which affect it; the cylinder and its fittings; the piston, piston-rod and connecting-rod; shafting, cranks and crank-shafts; foundations, bed-plates, columns, guides and framing; the condenser; pumps; valve and valve gear; valve diagrams; propellers; sea cocks and valves; auxiliary machinery; boilers, fuel, evaporation; boilers - tank boiler design and details; water-tube boilers; construction and detail of boilers; boil mountings and fittings; fitting in of machinery, starting and reversing of engines; weight and other particulars of machinery relating thereto; effect of weight, inertia and momentum, balancing the same; materials used by the marine engineer; oil and lubricants, engine friction; and tests and trials - their objects and methods.

The excessive wear of the piston rings and cylinder liners in a large bore low-speed marine diesel engine could be due to various factors. One of the most important tasks in assessing the main causes of excessive wear is the detection of the initial stages of the degradation of the sliding friction behaviour that leads to excessive wear. The piston rings and cylinder liners of diesel engines on board operating ships can experience scuffing and temperature-monitoring systems have been widely installed in engines to detect scuffing. Here an automatic analyser is installed to analyse the iron content in the cylinder drain oil at a piston underside on a ship to accumulate data to estimate the potential mechanism of excessive wear on the piston rings and cylinders. The effects of operating conditions are reported of a large-bore low-speed marine diesel engine focusing the wear of piston rings and cylinder liners based on the measured iron content in the cylinder drain oil with respect to the operating time and macroscopic and microscopic metallographic structure observations made on the piston rings and cylinder liners. The experimental results are presented from test beds experiments and laboratory experiments. In addition the potential mechanisms for the excessive and normal wear are proposed.

A pro-active safety management system for ship structures that quantifies the aging effect such as fatigue and corrosion on ship structural integrity is proposed as a new approach to the ships structural surveys that have conventionally been done according to a more passive management system. In a proposed fatigue management system called the Hull Fatigue Management System (HFMS) using Fatigue Damage Sensors (FDSs) it is an important problem to improve the prediction accuracy of hull fatigue life using the FDSs. The characteristics of the FDSs that are in use for fatigue life evaluation by monitoring structural members in ship structures are discussed in order to improve the prediction accuracy of fatigue life exposed to random wave loads such as storms under various loading conditions peculiar to ship structures. Factors affected by random loading against constant-amplitude loading and mean stress levels are introduced for the evaluation procedure using FDSs and confirmed by a series of fatigue testing and numerical simulations. This newly proposed fatigue life evaluation procedure using obtained factors is checked by comparison results of fatigue tests for a large structural model on which FDSs and strain gauges are provided simultaneously and to which random loads by assumption of storm patterns are applied under various mean stress levels. Practical application results of the FDS for an LNG Carrier for 5-year operation are discussed.

The Royal Navy's future aircraft carrier (CVF) HMS Queen Elizabeth will be the world's first aircraft carrier to adopt an IEP (integrated electric propulsion) system and one of the largest and most powerful electrically propelled ships in the world. CVF will also be the first electric ship for the navy designed to be so from the outset without any mechanical legacy constraints. The design has been some 10 years in the making and along the way there have been many twists and turns in the technical and commercial areas that have driven the technical solution. Here some insight is given from a power and propulsion perspective of where the carrier has come from and where she is now and where she might go in the future as we stand on the edge of the manufacturing phase. It is outlined how the current all-electric power and propulsion solution is proven but innovative capable but prudent and graceful rather than redundant. After a period of competition value engineering military and commercial equipment evaluation both the power and propulsion design and team is fixed and moving forward in a co-located alliance structure for the first time.

A five year contract for pipe installation with a flexible laying vessel capable to lay bundles up to 1500 water depth has been awarded by Petrobras to Brasflex the Brazilian subsidiary of the Coflexip Stena Offshore Group. The project is based on the conversion of an existing vessel the Sunrise which is now the deepest existing laying vessel. Practically the only parts of the vessel which did not have to be modified were the hull structure and the twin propulsion system. The main modification concerned the draft and vessel decks. Other modifications included: the installation of three rotating baskets with a total capacity of 3600 tons; the integration of outriggers in the aft vessel structure to support the vertical laying system; the installation of four retractable azimuth thrusters for the Dynamic Positioning with additional power generators and a complete power management and control system; and the installation of a new deckhouse. The laying capacities required were: minimum operating water depth of 1500 metres high storage capacity to permit long operational campaigns without necessity of re-loading laying and recovery of flexible bundles composed of 3 lines perform first and second end diverless connections on wellheads and manifolds laying single flexible lines up to 12 inch inside diameter and recovery of rigid pipes to connect flexible flowlines and risers and resume the installation.

Increasing ship speed is one of the recent trends in marine transport. A new concept for the design of high-speed hull forms is presented. It is based on the application of minimum wave resistance. The hull form designed according to this concept is a compound hull composed of elongated hull bodies located at bow and stern ends and a continuous surface piecing middle hull connecting each submerged body. The shape of the middle hull is determined mathematically by means of the calculus of variations in such a way that the wave resistance becomes minimum under a certain condition. The wave resistance of this hull form has been compared to that of a high-speed hull form designed in the conventional way. Model tank tests are carried out on both models. The agreement between computation and measurement is quite satisfactory. It is observed that the wave resistance of the hull form designed according to the proposed concept is reduced by half compared with conventional hull forms of high-speed ships at the Froude number over 0.4 where the so-called last hump which brings the high level of wave resistance is shown in the resistance curve. The result shows that the high level of wave resistance at the last hump is effectively suppressed by the proposed design. The feasibility of the new concept is evaluated by presenting sample designs. This shows that the proposed method is quite profitable in the fast ship market by supplying an innovative hull form of excellent behaviour at high-speed operation.

Many cracks were found at the connections of side longitudinal frames and transverse webs or transverse bulkheads in VLCCs whose main hull structures were constructed using higher tensile strength steel. A combination of loading by cargoes wave forces and bending moment of the hull and their interaction on complex structures of these members result in complicated stress state which make the fatigue evaluation very difficult. In order to clarify this behaviour fatigue strength tests were carried out simulating the actual wave loading in the form of storm model. Time histories of significant wave heights in the Pacific Ocean were settled in two types i.e. low wave height sea state and high wave height sea state based on the records of encountered data. Storms are divided into six models between these two sea states. Test specimen consists of a flat plate with square pieces on both sides of it. In fatigue strength tests cyclic loading of axial tensile stresses are given to the specimens. The maximum loading amplitudes are 1) one pattern of the biggest wave height model 2) variable loading of six models in accordance with the probability of occurrence in the Pacific Ocean. From the tests results the total numbers of storms can be estimated for the life of side longitudinal frames of the ships in service in the Pacific Ocean. This method is a very simplified method for the prediction of the lives of ship structures.

In recent years Wartsila has introduced a number of gas engine variants the latest being the Wartsila 50DF dual-fuel engine. This engine type represents the latest technical achievements in the large gas and Dual Fuel engine segment. It is built on the well-known Wartsila 46 diesel engine and is equipped with innovative designs in terms of gas admission system pilot fuel system and engine control previously introduced in the Wartsila 32 DF engine. As a result of an intensive development program this engine offers outstanding performance and reliability with minimised environmental impact. With an output of 5700 to 17100 kW a wide range of applications can be covered both marine as well as land-based power plants. TheW50DF engine has made a remarkable breakthrough in the LNG tanker applications as an alternative to the traditional steam machinery. Capability to operate on either boil-off gas or heavy-fuel oil in combination with high efficiency and high unit output are valued features in these applications. In addition a number of more traditional land-based power plants have been contracted. This paper presents the experience from the first W50DF engines in commercial operation both in LNG ships and in stationary land-based power plants. The installations are described and the running experience and performance of the engines are reported. In addition the functionality and reliability of individual components including the engine management system are covered. Parallels to the previously introduced 32DF are also drawn.