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AES 97 - First International Symposium and Exhibition on 'Civil or Military All Electric Ship' Paris France 13-14 March 1997. The all-electric ship incorporates a single power network supplied by a primary energy source made up of generators distributed within the ship. This primary source produces electricity and is distributed to all of the ship's electric applications. The following topics are discussed in the symposium sessions: electric propulsion motors, naval architecture, electrical equipment, technology and systems and anaerobic propulsion. The symposium aimed to assess current world-wide studies, projects and developments relating to electric ships. Separate supplement contains presentation slides for 4 papers: Permanent magnet propulsion motor technology and ship design, Propeller with combined disc motor for hydrojet propulsion, Savings in installed power, fuel consumption and emissions with electric propulsion and a New type of permanent field machines for diesel electric propulsion systems.

Today many ships cruise liners and Navy vessels use an electric podded propulsion. These AES (all electric ships) need an important electric power. Consequently high currents in ELFE (extremely low frequencies) flow through cables and equipment. These alternative currents could generate an important underwater electromagnetic field. The level of this field has to be quantified together with its impact on the signature of this kind of ship. Then GESMA carried out electromagnetic measurements using a multi-sensors underwater and autonomous facility named AMI. It was placed on the route of a few megawatts podded ship at one hundred meters depth from the surface. We observed a non-negligible radiated electric field.

This paper presents the findings of a numerical investigation into the strength of minimum structure platforms subject to a ship impact. The study has identified important design issues that should be addressed in order to improve the survivability and continued serviceability of minimum structures after a ship impact. It was found that due to a lack of research effort design guidelines governing ship impact on minimum structures are lacking in comparison with conventional jacket platforms. In particular requirements governing the minimum amount of plastic energy absorption in minimum structures are not clearly defined. Ship impact analyses were therefore carried out in order to compare their structural integrity with that for a jacket under ship collision conditions and to evaluate the effects on their ultimate strength.

ARTs (anti-rolling tanks) are a good roll stabiliser for ships. A study of an ART is presented together with its effects on ship roll motion. Experiments are carried out in regular sinusoidal waves of small amplitude and in irregular waves. For regular waves experiments were carried out in constant wave heights and constant wave slopes. For irregular waves experiments were carried out in two idealised wave spectra ITTC (international towing tank conference) and Jonswap (Joint North Sea Wave Project). A view of the effects of the designed ART on roll motion of the model ship is presented. Results shown that when using the model ship with the ART the roll stability of the model ship is increased. The best effects are obtained with the model ship when experimenting with a wave frequency near to its natural roll frequency.

The estimation of the numerical values of roll damping is an essential step in design of ship or other offshore structures. It remains a difficult task because of ship rolling and other highly non-linear phenomena such as fluid separation and vortex shedding. Therefore roll damping cannot be calculated by theory method which is different from other ship motions. The most common method in ship design is empirical formula for roll damping. One series of half empirical formulae were proposed by Ikeda (1977 and 1978). These were derived from a series of model experiments. Despite some minor changes these formulae are still widely used today. With the development of CFD technology the unsteady Navier-Stokes equation has been used to study roll damping. In recent years some meshless methods have been proposed. In this paper in order to simulate the rolling of different 2-D ship sections of series 60 a meshless numerical simulation method is presented. S.S.0.5 S.S.5.0 and S.S.7.0 section are selected for simulation. An area-time average method is used for pressure fluctuation in simulation

A SWATHS (small waterline plane area twin hulled ship) is a ship with high performance developed in the late 20th century. As marine transport modes have diversified together with the exploitation of ocean resources the requirements for the ship's performance have changed gradually. The emphasis is now on improving the sea-keeping capability of the ship rather than just concentrating on improving its speed. Some background is given on the development of SWATHS in various countries. Next the arrangement and ship form of SWATHS is presented. After this the features of SWATHS are discussed followed by some problems of ship form and structure with this type of vessel. Finally the application of SWATHS is discussed.

The development of thin ship theory for the prediction of the near-field wave system for high-speed displacement craft is described. This theory provides a description of the component waves of the wave system and the wave pattern along the path of the ship. This may then be used as input to wave propagation and transformation models. The theory is suitable both for monohulls and multihulls and can be used effectively for slender hulls. The development of methods to improve the theoretical modelling of transom sterns operational trim and shallow water are discussed. Theoretically generated near-field wave patterns are found to compare well with model measurements and the calculated wave resistance to be close to the measured wave pattern resistance.

Hydrogen fuelled aero-derivative gas turbines for marine propulsion may offer the potential to significantly increase container ship transport efficiency. A study has been conducted into the technical and economic feasibility of a hydrogen fuelled long-haul feeder container ship. The properties of hydrogen offer the potential for increased payload particularly in long-haul operation which in turn improves economics. The research presented here focuses on the design and operation of a liquid hydrogen fuelled high-speed (64 knots) foil-assisted catamaran (FAC) container feeder ship (600 TEU) and the associated port/terminal facilities.

The approach to safety management of ship operations has been moving towards shore-based management relying on two-way ship-shore communication techniques. A study to establish a ship-shore communication network using satellite communication technology between the Fukae Maru and the base station in the Fukae campus is outlined. It is aimed to develop assessment technology that is capable of quantitively assessing safety in various ship operating modes required for assisting safe ship operation from the shore side and to promote research and development on safety management technology by incorporating assessment technology into the prototype experiment system for the ship-shore communication network.

Some of the results of a comprehensive research project on ship structural safety carried out by Nippon Kaiji Kyokai (also known as ClassNK) in co-operation with several Japanese universities and ship research organisations in order to propose a rational transparent and yet practical assessment method of ship structural strength to ship designers ship operators and concerned parties in the maritime community are presented here.The significant findings presented in this paper include four different shortterm sea states practical formulae for design loads a realistic fatigue assessment method considering the effect of mean stress and a probabilistic simulation model of the corrosion process of ship structures. The details of a new direct strength analysis system incorporating the above findings are also described.

Conf in Southampton UK July 1992. Papers are - Ship handling training using physical simulators Aiding port design using ship manoeuvring computer simulation The role of ship manoeuvring prediction and simulation techniques in ship projects - case studies of a Baltic cruise ferry Practical ship manoeuvring models for real ship manoeuvring problems Manoeuvring characteristics of a ship in deep and shallow waters as a function of loading condition Realistic simulation of tug forces on a manoeuvring vessel Prediction of stopping manoeuvres of a ship in shallow water Development of SWATHMA a manoeuvring tool for small waterplane area twin hull ships Development of a four degrees of freedom linear ship manoeuvring mathematical model The effects of the environment on the stability and turning of ships The effects of skegs and stern shape on the dynamic stability of ships Trials to investigate the directional control of a fast lifeboat Investigation of performance characteristics of high speed planing craft

Piloting and shiphandling is about individual judgements based on knowledge allied to practical experience. The chapters cover basic ship handling (including reducing a ship's speed to manoeuvre and turn around), transverse thrust and turning a ship short round, centre of turn and sideways slip, the effect of wind and other external forces on ships, assessing a ship for manoeuvring, general berthing and unberthing guidelines, berthing a ship using an anchor, berthing and unberthing using tugs, thrusters, examples and calculations to approach a berth, manoeuvring in fog by radar, anchoring a ship, passage planning, port approaches and navigating narrow channels, tug and tow, handling characteristics of different ship shapes, tidal streams, squat, interaction, reaction, drag and grounding, and miscellaneous items.

The role of tanks testing versus CFD (computational fluid dynamics) in ship hydrodynamic design is addressed. A variety of ship flows of interest in design are identified and a general discussion of the successes and challenges faced by tank testing and CFD is carried out. The primary accomplishments and challenges faced by computation are identified. Two areas of ship hydrodynamic design are addressed in some detail: the evaluation of the ship wake and resistance in calm water; and the ship seakeeping in waves. Various types of ship hulls are identified and the performance and use of specific computational methods in their hydrodynamic design is addressed.

The development and use of a physics-based mathematical model for ship and ship subsystem design and assessment is described. The model called PASS (parametric analysis of ship systems) is unique in that it emphasises the use of algorithms derived from first-principle physics rather than from empirical data to characterise all major subsystems and their synergistic relationship to the overall ship. This is to ensure that newly emerging technologies can be realistically modelled without being unduly biased by existing trends in ship or ship-subsystem design. The overall objective was to develop a design synthesis tool that recognises current or projected future fleet requirements and operational proprieties and permits a realistic assessment to be made of the cost-benefits of emerging technologies. The model uses an object-orientated architecture and a Windows-based GUI (graphical user interface) for easy use. Also described are several design examples for military and commercial ships as a means to illustrate the use of the PASS programme.

Ship crankiness usually manifests itself in large heeling angles significantly exceeding the roll amplitudes that correspond to the exciting moment at given sea state and sailing conditions. The phenomenon is considered on the basis of modern theory of ship motions and the corresponding numerical measure for this ship quality is found - the amplitude of steady parametric rolling motion. It is suggested that ship stability in following seaway conditions can be checked using the criterion which restricts parametric roll amplitude.

This guide, based on best advice from industry, has been used as the basis for national regulations on ship-to-ship (STS) transfer operations covering petroleum. This new edition has been updated to reflect current good operating practice. The guide is aimed at providing advice for masters, marine superintendents and others responsible for planning STS transfer operations. It is primarily directed to the transfer of crude oil and petroleum products between ocean-going ships. It contains recommendations on conditions and requirements, safety, communication, operational preparations before manoeuvring, manoeuvring and mooring, procedures alongside, unmooring, equipment and emergencies.

This guide on marine insurance in ship financing has sections on shipowners' insurance; important coverage issues on the operators' various insurances; insurance brokers; assignment and acknowledgement of the bank's interests; underwriting security; other issues of interest to marine financiers; marine insurance claims; ship regulation and certification; maritime liens and other claims against a ship; insurance considerations in foreclosing and enforcing on a ship mortgage; insurances and guarantees for marine financiers; and brokers' clauses. There is also a glossary and a directory of ship financier lawyers.

13rd International Marine Systems Design Conf held Pittsburgh 8-10 June 1988 Papers are The subcavitating/supercavitating hybrid propeller An advanced method for design of optimal ducted propellers behind bodies of revolution Optimal hull forms for fishing vessels A knowledge-based system architecture for control of underwater vehicles Roll reduction by rudder control An integrated rig management system for a semisubmersible floating production vessel Computer aided navigation system (CANSY-II) Evaluation of impact loads associated with flare slamming Surface effect ship loads; lessons learnt and their implications for other advanced marine vehicles Advanced ship structural design and maintenance Methods of incorporating design for production considerations into concept design investigations Achieving customer and marketing orientation in marine transport system design Incorporating a seakeeping capability in a computer aided preliminary design system Hull form design - only a matter of the computer ? The components of the propulsive efficiency of ships in relation to the design procedure Design conception and CAE/CAD of hull form Direct curve and surface manipulation for hull form design Intelligent computer aid in marine design and ocean engineering Ship synthesis model morphology Teaching design for students of marine technology Operational aspects in ship design; the case of the roll on/roll off vessel The productive experience of 3D CAD/CAM techniques applied to ship design and construction A new concept for neat fit ship propulsion