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This paper evaluates the performance of an industrial power electronic building block (PEBB) controller in a large scale all electric ship power system by means of real-time hardware in the loop (RT-HIL) simulation. As an example relevant to future all electric navy ships transients originating from the charging circuit of a pulse power load integrated with the prolusion motor drive and its impact on the system are studied. Different solutions to mitigate the impact by coordinating the power sharing between the pulse load's energy storage system and the ship propulsion motor drive are proposed and evaluated. The second part of the paper discusses how the RT-HIL tool can be used for system-wide performance optimization.

A method is proposed for the safe and efficient transportation of large quantities of water in general cargo ships. This method involves placing large fluid bags in the cargo hold. Pressure by sloshing occurs on the sidewall of the hull by the liquid bags and the strength seems to vary with the distance between the rotation centre and the liquid bag centre of gravity. The experiment with a 1:10 scale model of GT499-type cargo ship is carried out to confirm the safety and the feasibility of this bag system. From these results it is clarified that the method of water transportation with hold size liquid bag can decrease the sloshing pressure drastically. Furthermore the sloshing pressure increases as the distance between the liquid bag and the centre of rotation increases - the tendency becomes predominant in the rolling period under 10 seconds.

The Battle Damage Control System (BDCS) provides electronic plotting of ships' damage condition and status with the capability of onboard training from individual to full crew level. The BDCS is a distributed architecture system with digital microprocessor based nodes connected to a database with adequate redundancy. BDCS provides the operator consoles with data acquisition and control electronics sensors and functional software required for the control and monitoring of damage control systems and related vital machinery. Software and functional requirements including default screen displays expert systems operating modes interactive plotting and harbour to ship and ship to ship interfaces are discussed. The advantages of BDCS include real-time update voice traffic reduction weight and space savings ease of expansion and maintenance and less manpower.

A growing debate on energy demand and exhaust emissions for transport in general has made it necessary to have precise methods for calculating the energy demand of different types of transport. The background is presented for a method of calculating the energy demand for different ship types using only a relatively few but important parameters. It is an empirical method based on a statistical analysis of the main parameters of different ship types in order to establish representative relationships between the cargo capacity and the ships main dimensions. On this basis it has been possible to calculate the necessary propulsive power by using well-established empirical power prediction methods. By combining the statistical analysis with a subsequent power prediction it has been possible to develop a method which can calculate the energy consumption as a function of only three general parameters: the size of the ship (more precisely the capacity); the ship's speed; and the average cargo use.

Coiled tubing has been used to deploy perforating guns for several years and use of this technology has enabled many operators to complete high-angle wells with optimum completion designs. Until recently however this perforating method was not used in Brazil because of the complexity and risks involved particularly on offshore platforms (semi- submersible rigs and-or drill ships) where daily costs are extremely high. The first experience of CTCP (coiled-tubing- conveyed perforating) performed offshore in a horizontal well in this South American country is described. Data tables photographs and diagrams appear on pages 7 to 16.

Excessive levels of forced excitation in ships has been identified as coming from cavity flare up and collapse on a propeller blade as it encounters the low velocity region near to the blade's vertical upright position. The problem arises because of incompatibility of the propeller design and hull flow. The role of analytical methods for assessing the propeller and wake are considered. The method used at the British Ship Research Association is outlined together with experience of its use in estimating cavitation-induced hull pressures for four ship and model studies which were undertaken as part of the Propeller Excited Vibration project carried out at BSRA between 1974 and 1977.

Conf held in Florence Italy April 1991. Papers are - Double-cone burners for gas turbine type 9 retrofit application Development of low-NOx gas turbine combustor for natural gas fuel Combustion characteristics of a gas turbine catalytic combustor Application of a Navier-Stokes analysis to turbomachinery blade- cascade flows The aerodynamic design principles methods and test results of an axial turbine of the SS-turbocharger series for ships diesels Application of three-dimensional inviscid and viscous codes to the aerodynamic design of an advanced gas turbine The optimized design method of a centrifugal compressor volute Operating experience with dry low NOx hybrid burners Development of the ceramic combustor for gas turbine at high specific combustion intensity Development of ceramic combustion for gas turbine The influence of high lip-to-slot-thickness on film cooling effectiveness

Electric propulsion systems have been used for many years. However up till now the applications were limited to certain types of vessel. The requirement of high-powered installation to supply the auxiliaries at quay and the development of new types of diesel engine give a fresh opportunity to extend electric propulsion to other types of vessel such as LNG carriers. The increasing market for LNG carriers has led ABB and Bureau Veritas to study and propose an innovative propulsion system. ABB has delivered a complete propulsion drive system based on 2 x 14 mW medium-speed propulsion motors and BV will classify the two vessels. The system as installed onboard these two ships in two different aspects (classification and technical) is presented.

Coastal shipping traffic was essential to the growth of London as a city in terms of population size and geographical area. There is no doubt that London's population grew rapidly in the late 18th and early 19th centuries. The coastal ship could carry bulky heavy low-value products in large consignments over long distances at comparatively low cost. Many of the goods required for industrialisation and the urbanisation that accompanied it were just such products. In addition to needing bulky inputs the industrial city created large quantities of waste products. These were of very low value and needed cheap and regular removal. A combination of river barges for short distance journeys and coastal ships to the further destinations kept these potentially overwhelming quantities of by-products under control.

The marine coatings industry is a major supplier to shipping. Marine coatings are essential to the operational needs of ships. The industry along with the marine industry as a whole has faced demands of improving efficiency while also improving the environment. It is described how coatings can contribute on both fronts. Some of the improvements have been identified by shipyards or operators themselves others have resulted from a deeper insight into the processes gained from working closely with customers. It is predicted that the substitution of more environmentally acceptable alternatives for TBT as well as the increasing use of fouling release technology for certain ship types will further improve the environment.

Generic composites are two or more distinctly different materials combined into one structure to perform a function neither material is capable of doing singly. FRP (fibre reinforced plastic) is a composite with many advantages such as lightweight high specific strength ease of forming resistance to corrosion and long life. Such composites are the material of choice for recreational boats. Recently though composites have been used for 57.3 m (188 ft) minehunters and 49 m (161 ft) yachts which 10 years ago would have been at the upper limits of size limitations. Composites are used for sections of large steel vessels including non-pressure hull decking noise sections sails and diving planes for submarines weapons enclosures for destroyers and funnels on cruise ships. Potential uses on large cargo vessels and auxiliary vessels include bow fairings hatch covers stern fairings deck machinery enclosures and non-structural interiors. Composites have also been used as a complete hull restoration for a vintage steel yacht. Current usage is reviewed and future potential on the use of composites on larger vessels is explored. Issues of damage tolerance

New mid-range engines from Sulzer include the RTA48T and RTA58T designs with long piston strokes for use in tankers and bulkers. MAN B&W's S46MC will not be available until 1997. Wartsila's 38 medium speed diesel engine has been chosen for Carnival Cruise Line's Fantasy class but Sulzer's long-awaited ZA50S will be introduced in 1996 for use in both cruise ships and ferries. MAN B&W's Holeby division has developed the L16/24 heavy fuel burning engine which will eventually replace the 230mm and 280mm models. Fast light weight ferries are an attractive market for engine manufacturers including MTU Ruston and Caterpillar. Aero-engine derived gas turbines now propel commercial ferries with unit powers ranging from Allied Signal's 3000kW TF40 and General Electric's 4400kW LM500 to the Turbo Power / Mitsubishi 24250 MFT8 and GE's 26000 LM2500.

Corrosion found over recent years in Royal Navy ships is discussed and the nature of the corrosion layer is considered. Laboratory investigation of corrosion in the absence of water and by turbine oils is described and the effect of additives and the corrosion mechanism are outlined. Beaker and flask test procedures were developed. Results presented indicate that lubricating oil water and bearing metal interact to produce tin oxide bearing corrosion. Beneficial antioxidant and rust inhibitor additives corrosive nature of EP additives and active corrosion prevention by mild EP turbine oils 8 and 11 are discussed. Recommended elimination of water from system or maintenance of chloride free system and beneficial nature of relatively small changes in alloy composition namely addition of cadmium are reported.

Navy ships need to have the flexibility to manoeuvre to avoid threats and provide expansive operating envelopes for helicopter operations to maximise operational effectiveness. Safe operating limits are required to enable the flight crew and deck crew to carry out particular on-deck operations. These include landing and takeoff traversing the helicopter from the hangar to the flight deck or use of a particular lashing scheme or restraint system to secure the helicopter. Traditionally RAN limits have been based on simulation for a wide range of conditions and have been conservatively defined using just pitch and roll at worst case wave encounter frequencies. Little account has been made for the effects of ship manoeuvring and list. AVT is developing a ship based helicopter aid termed the DAD (Deck Availability Designator). The system couples the Australian DSTO (Defence Science and Technology Organisation) Ondeck helicopter-ship dynamic simulation code with an IMU (Inertial Motion Unit) to provide a real time predictive capability of the helicopters response to actual ship motion as well as an estimate of the loads transferred through the helicopter.

The design of an optimised monohull called EHSCV (European high-speed cargo vessel) is presented. Different ship platform alternatives such as catamarans or surface effect ships are evaluated and a 40-knots monohull vessel is selected. Its design hypotheses and resulting main characteristics are described. Reasonable operating costs and reliable operation are considered. Special emphasis is placed on the hydrodynamic aspects of the design in order to achieve attractive operational costs. Two different sets of hull lines are considered and comparative numerical and experimental studies are carried out. Finally the different design actions used to improve the selected hull lines are described.

The development and demonstration of a CAD-CFD-optimiser-integrated SBD system is presented with particular focus on the design of high-speed ships. The main objective is system development and the demonstration of the capability which justifies use of simplified design constraints and conditions. An overview of the present method is given and results are presented and discussed for bow optimisation of a high-speed naval surface combatant DTMB Model 5415 for minimum total resistance and sea-keeping merit functions. Although the complete results are not yet presented it so far appears that overall scheme developed performs well and is very promising. After more detailed evaluation and further demonstrations the method will be an effective SBD tool applicable for practical ship hull form design.

In order to promote quality shipping the state government of Bremen has decided to pave the way for an attractive and efficient maritime incentive system. The system integrates existing maritime incentive and certification systems and leads to an assessment of the current quality performance on board and ashore. Incentives will have to be considered so that recognisable advantages for maritime quality performance can be granted. Facing the legitimate approach to charge the use of Global Commons e.g. the coastal waters it appears appropriate to increase the shipping industry's contributions to these costs related to contingency planning and combat actions but at the same time to allow for reductions for well run ships i.e. quality shipping.

A directory of Russian merchant ships, this part focusing on freighters of up to 5,000 dwt carrying capacity. Written in German.

A directory of Russian merchant ships, this part focusing on freighters of up to 5,000 dwt carrying capacity. Written in German.

The protection of ship's power system is a key core technology in the research of security of ship's power system. With the development of a ship's power system its network structure is becoming more complex. Making selective protection of such power system is also more difficult. While differential protection according to its own principle can provide a kind of entirely selective protection to system short-circuit fault so there is significant advantage when widely applying the differential protection in ship's power system. The differential protection can supply highly effective protection to short circuit fault of 2-node lines and multi-node buses. It also can provide the fault locating information for the adjustment of the whole system's protection strategy and for the control scheme of the reconfiguration. In this paper the necessity of applying the differential protection in ship's power system and the applying principle of the 2-node lines and multi-node buses protection are introduced. Then a digital realize method is proposed and its main modules' function are introduced. At last the actual performance result of the equipment sample realized by the method above