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SCRs (steel catenary risers) have been an attractive choice for deepwater field developments. However standard SCRs may not be feasible for large motion vessels especially in harsh environment. TCRs (titanium catenary risers) or SCRs with titanium sections-components will expand the applicability of metal catenary risers. A fully developed metal riser concept for the Kristin field in the North Sea is summarised. Metal gas export risers are an attractive alternative to flexible gas export risers. Due to the harsh environment and the large motion semi submersible host platform the titanium riser is the only feasible metal riser concept. The design of metal risers in harsh North Sea environment poses many design challenges with regard to buckling and fatigue. A feasible and robust riser configuration is presented which consists of a catenary titanium riser with varying weight coating to optimise the dynamic behaviour. The design challenges in the pontoon joint are also discussed. In addition to optimise the cost of the riser steel sections are used where the flexibility or superior fatigue performance of titanium is not required. The developed riser configuration is less sensitive to soil parameters and also has good fatigue performance. Similar riser design can be applied for deepwater large diameter export risers where traditional steel catenary risers have design limitations. A well-proven installation method is outlined consisting of onshore riser assembly-fabrication and sheltX26227 Titanium cooling coils for service ship applications

Over the past few years there has been a lot of research and study of underwater vehicles which use sonar sensors in their missions. A small test-bed ROV ISRO is presented. ROV ISRO is of a frame type and is equipped with four thrusters. These four thrusters enable the ROV ISRO to control four motions: surge sway yaw and heave with the use of sonar sensors. ROV ISRO has been developed for the inspection of ship hulls marine structures plants in an ocean or a river and so on. When ROV ISRO inspects it needs ROV ISRO's position control system because of movement from its specific position and to avoid collision with underwater structures. In this paper a small ROV is developed and the position control system is verified through simulation and experiment using sonar sensors. A detailed specification of the ROV ISRO model is presented. The ROV ISRO modelling is explained and the PD controller is designed. A simulation model is created in MATLAB-SIMULINK. ROV ISRO's water tank experiment is explained and the results are analysed. Finally

In recent years there has been a significant push towards IEP (integrated electric propulsion and power generation systems) for Naval ships. Currently the only all-electric vessels in service with RAN (the Royal Australian Navy) are six Collins class submarines and two hydrographic ships. The integration of electric propulsion and power generation for warships is said to promote flexibility in positioning machinery and to reduce signatures and vulnerability. Benefits are claimed for space and fuel efficiency but calculations on several generic ship classes for RAN raised doubts about these claims particularly for a destroyer. The cooling of electric propulsion systems may present serious challenges for operation in tropical waters and very limited signatures information is available. DSTO is engaged with University programs on electrical systems and has begun work on electromagnetic signature ranging of all-electric vessels. The detailed considerations of particular classes are not addressed. The focus is rather on addressing the common areas revealing specific advantages or disadvantages of integrated electric systems and also on considering the contrasting needs of a surface combatant and a military transport vessel. DSTO has also sought to consider some of the issues not yet thoroughly canvassed in literature to determine what is known about reliability maintainability and the various signature issues associated with such a significant change.

In the coming years there will be a growing demand for FPSOs (floating production and storage units) for ultra deep waters. In the Gulf of Mexico the process will be accelerated by the technical and economical limitations inherent to other type of concepts the lack of pipeline infrastructure in such deep areas and the wide acceptance of the FPSO concept by Shelf Authorities. One of the most critical issues in the design of FPSOs for ultra deep waters will be the selection of the most cost-efficient station-keeping system for the specified operational requirements. Standard solutions based on internal turret and thruster-assisted mooring systems are already being offered by the industry. However beyond certain water depths the technical and economical constraints associated with the use of mooring systems may favour other concepts potentially more attractive and cost-efficient such as a fully dynamically positioned FPSO (DP-FPSO). This DP-FPSO concept is proposed. It provides an innovative and cost-effective solution to meet the challenges of ultra deepwater production by using existing and proven technology in the offshore industry. The paper shows the technical feasibility of the concept by analysis model testing detailed engineering of the various sub-systems and risk and reliability studies. This concept marries state-of-the-art FPSO technology and latest generation drill ship technology for dynamic positioning and operation in ultra deep waters. This system can either be u

Traditionally offshore oil and gas fields in the Asia Pacific region have been located in shallow to intermediate water depths. Technological developments have consequently focused on bottom fixed platforms or floating platforms with relatively benign conditions. New fields are located further offshore in deeper waters exceeding 1000 m water depth. This necessitated import of new technologies from elsewhere principally from the Gulf of Mexico. Offshore developments to date that use floating systems have deployed ship shaped platforms the so-called FPSO (floating production storage and offloading) or semi-submersibles with flexible risers connected to the seabed. Several nearby fields are developed using subsea hubs that transmit the produced fluids to the facility. This trend has recently changed with the development of West Seno field offshore Indonesia and the Kikeh field offshore Malaysia. Both these developments have used the so-called 'dry tree' technology marking perhaps a new era for innovation and technological development in the Asia Pacific region. The development of dry tree technology around the world is explored focusing on the spar technology and its application. The success of the TLP (tension leg platform) technology for the West Seno is discussed and compared with the proposed spar application for the Kikeh field. New challenges presented for the Asia Pacific regional area are discussed.

There is growing concern in the shipping industry about poor quality bunkers inflicting serious damage on diesel engines particularly the fuel injection equipment. The problems and damage caused are explained. Incidents of waste contaminated fuels are described. Such damage can be traced to waste chemical contaminants dumped in the bunkers. In most cases routine analysis of fuel samples based on ISO 8217 would not be able to uncover sub-standard fuel properties. Higher end analysis is required to detect and identify the waste contaminants. The use of FT-IR (Fourier-transformed infra-red spectroscopy) GC-MS (gas chromatography or mass spectrometry) and other high-end analytical techniques to positively detect and identify the unusual waste contaminants is discussed. A brief description of these techniques is given. It is recommended that if waste contamination of fuels is suspected the use of Acid Number analysis is used to determine the level of acidic constituents in the bunker fuels as well as FT-IR GC-MS to confirm the presence and possible identification of the waste chemicals. Ship operators are cautioned that acid number results do not have consistent correlation with the damage attributed top waste contaminated fuel. Blanket testing of all bunker fuels would not be economical or practical but chief engineers should alert fuel testers immediately if they encounter unusual and unexplained engine problems.

Determination of hydrodynamic propeller forces and moments is of outmost importance for accurate shaft alignment calculations and vibrations predictions. Values of propeller forces and moments depend of propeller geometry and wake field. They are usually determined using a theoretical approach (computer software) or an experimental approach (model basin measurements). A new approach developed by Tecnitas/Bureau Veritas for determination of values of propeller forces and moments is presented based on results of measured deformations of line shafting. The methodology consists in performing simultaneous calculations of line shafting position and stiffness characteristics of its elastic supports including oil film stifness in running conditions. this approach has two main advantages. The first one is a good accuracy due to the fact that measurements of line shafting deformations can be accurately performed using contactless transducers. The second advantage is that modification of values of propeller forces and moments as a function of rudder angle value ship in operation can be investigated. The better knowledge of influence of rudder angle on propeller forces and moments will give a more accurate assessment of the safety margin on shaft alignment conditions particularly for aft and forward stern tube bushes. This safety margin is needed to accommodate effects of rudder angle which can be at the origin of stern tube bearing failures. Alignment conditions must of course be calculated taking into account all relevant parameters such as hull flexibility hull deformations oil film effects in runniX30246 Determination of inception cavitation parameters for 2-D bodies in boundless flow by means of cavitation tests in hydrodynamic tunnels

The early application of HF (Human Factors) is essential to obtain the maximum benefit in the design and development of systems. This approach is being adopted by the MoD for the UK's MARS (Military Afloat Reach and Sustainability programme) which is currently in the early stages of acquisition. MARS is intended to replace a large part of the Royal Fleet Auxiliary fleet as they are progressively withdrawn from service. It will provide the RN (Royal Navy) with three core capabilities: solid and liquid consumables for embarked forces joint sea-based logistics and forward aviation support for rotary wing operations. Current planning for the MARS requirement envisages acquiring three types of ships consisting of Fleet Tankers JSBL (Joint Sea-Based Logistics) vessels and FSS (Fleet Solid-Support) ships. The MARS IPT (Integrated Project Team) has commissioned Quintec Associates Ltd to carry out an Early HF Assessment in order to provide a baseline set of Human Factors data which will be used to calculate the three complements determine where ship design lessons should be incorporated into the MARS platforms and compile a draft set of HFs requirements. Here the approach taken in carrying out such an early HF assessment is described. Concepts such as 'people-related requirements' 'manpower capability modules' and a bespoke Quintec complement aggregation tool called Q-CAT are described.

The potential problems of organisms introduced by ballast water are well documented. According to MEPC (the Marine Environment Protection Committee) a new world Ballast Water Convention is to come into force. All ships including submersibles floating craft FSUs and FPSOs are to manage their ballast water in accordance with an approved Ballast Water Management Plan and record such management in a Ballast Water Record Book. As a result of these regulations there is a need for a proven viable cost-effective ballast water treatment system by 2007. This will allow ship designers to specify and incorporate such devices into ships that begin construction after 1st January 2009. Land-based work on a BWT system using on-site hypochlorite generation is summarised. One method used to treat ballast water is the electrolytic generation of sodium hypochlorite from seawater which has proved to be a simple and safe method of handling and injecting a biocide into water. After the hypochlorite oxidises organisms it reverts back to the chloride ion. Mesocosm-scale testing of this technology combined with filtration using organisms from Puget Sound Washington showed that hypochlorite generation and use may be a viable method to eliminate aquatic nuisance species from ballast water while minimising disinfection byproducts and residual toxicity.

The cruise industry is under increasing scrutiny from US Federal Agencies to determine the necessity to legislate in the area of environmental performance for cruise vessels operating in US waters. What is not clearly being understood by certain organisations is the extent of activity currently undertaken by cruise ship companies to control all aspects of waste generation through well-established programs implemented in accordance with existing international mandatory regulations. In order to both complement and facilitate the assessment of environmental impacts and to further pre-empt future legislation in this area Lloyd's Register has developed EP rules (environmental protection rules for the control of operational pollution. These rules provide a prescriptive means to control environmental equipment and systems and establish criteria for performance that far exceed the existing regulatory requirements. Whereas existing specifications concentrate in the area of hardware (MARPOL SOLAS CFRs Class) and the software (ISM ISO 9000 and 14000) on an individual basis the EP rules are designed to verify compliance with stringent environmental performance criteria combining inspection and audit to address all hardware and software issues. The Rules consist of essential core elements and optional more stringent requirements. With the current levels of regulatory scrutiny within the cruise industry the system enables owners to highlight substantial investment in particular aspects of pollution control whilst demonstrating a101380

An EIS (environmental impact statement) is presented. This has been prepared by MMS (the United States Department of the Interior Minerals Management Service) to evaluate potential environmental effects of the proposed use of FPSO (floating production storage and offloading) systems in the deepwater areas of the Western and Central Planning Areas of the Gulf of Mexico OCS (Outer Continental Shelf). The aim of the MMS is to manage the mineral resources in this area in an environmentally sound and safe manner. The FPSO EIS examines the potential issues and environmental impacts associated with the petroleum industry's proposed use of FPSO's on the OCS of the Gulf of Mexico. The EIS considers a generic FPSO system and operation as well as a range of technical variations. The 'base case' FPSO is a moored double-hulled ship-shaped vessel with one million barrels of crude oil storage capability. In accordance with NEPA the Government's decision will be detailed in a ROD (Record of Decision). The ROD represents the culmination of the NEPA process and summarises the proposed action and alternatives the impact conclusions of the EIS and other information considered in reaching the programmatic decision on the proposed use of FPSO's. The ROD has not yet been issued.

The problem of ship funnel exhaust is often studied through flow visualisation using smoke in a wind tunnel. It is a very useful tool for the naval architect to ensure that the funnel exhaust will not interfere during operation. Naval ships are particularly prone to smoke nuisance problems since they tend to favour short funnel heights because of competition for topside space. Flow visualisation studies are presented. These were carried out to understand the interaction between a bluff body air wake (of the funnel and superstructure or mast) and the ship's exhaust on naval ships. As a first step the analysis of the exhaust smoke-superstructure interaction was carried out in a wind tunnel for a generic frigate shape. Four variants of the superstructure configuration with progressive introduction of the structures on the topside (i.e. the superstructure or mast upstream and down stream of the funnel) were investigated in the wind tunnel at two velocity ratios through flow visualisation studies to understand their effect on the exhaust plume path. Apart from providing an insight into the process of plume dispersion in the vicinity of the funnel and other structures on topside of naval ships the results of the flow visualisation of the CFD (computational fluid dynamics) simulations (including particle tracing) of the exhaust smoke-superstructure interaction for cruise vessels ferries yachts as well as naval ships.

Two Swedish research projects concerning lightweight ship building LASS (Lightweight construction applications at sea) and DIBS (Design basis for fires at sea) jointly conducted large-scale fire tests in December 2007. The tests were also supported by a DNV-led subgroup within the EU-project SAFEDOR. For the experiments a two bed cabin and corridor RoPax replicate surrounded by a properly insulated FRP (Fibre Reinforce Plastic) composite superstructure were built in the SP fire lab in Boras Sweden. All materials used (bedding materials flooring materials etc) except the composite were materials one would expect to find on a standard RoPax vessel. Further was a realistic amount of luggage placed in the cabin. Fire was initiated by igniting a small wood crib placed in the lower left hand side cabin bed. The intensity and duration of the fire that developed when the cabin door was left open and the sprinkler was disconnected was somewhat surprising. The main idea of the project was to design experiments to resemble possible fires in a RoPax cabin. The objectives were to study design fires e.g. fire development and influence of sprinklers ventilation etc and to evaluate the behaviour of a composite structure under realistic fire conditions.

Accurate prediction of the hull resistance estimation of the achievable speed and optimization of the hull form for minimising the resistance are crucial points in the design of every new vessel because structural design of the hull cannot be started before the final hull lines are developed. Minimisation of hull resistance and ship motions is important in the design of modern vessels. Resistance calculations by CFD based on RANS equations are time consuming and need much attention to grid generation turbulence model selection calculation of the free surface and dynamic trim. That is why simpler panel methods are still in use because they can give a quick result on the wave-making resistance and pressure distribution. A panel code has been used at Austal for optimisation of multi-hulls for several years. For this investigation panels were distributed on the hull and free surface. The final wave pattern running trim and sinkage of the hull were determined in an iterative procedure. Solutions for the non-linear boundary condition were found in most cases. The linear boundary condition was used instead where the diverging solution took place usually due to a pronounced stern breaking wave.

There is high demand in the ship building market most Far East shipyards are concentrating on building sister vessels for to maximize their productivity. MHI (Mitsubishi Heavy Industries) has chosen another way - building many tailor-made vessels for niche markets. Integrated 3D CAE software packages are currently available for the early design stage and are widely used in many fields of naval architectural calculation. These software packages have various useful functions based on integrated common databases. However shipyard engineers still want to integrate their own in-house applications and database with 3D commercial software. MHI (Mitsubishi Heavy Industries Ltd) has developed an integrated 3D design environment for the early design stage based on the NAPA application and its customisation tool called the NAPA Manager. In this integrated 3D environment the designer can use the original NAPA functions and the shipyard's in-house applications and database asset. This paper presents a practical approach for the construction of an integrated 3D design environment for early design stage. The environment enables designers to generate a 3D model efficiently and also to accelerate standardisation of the design process by using the NAPA Manager's process template. For some processes such as performance estimation the use of in-house application and existing database of MHI which store thousands of model test results was decided. These in-hoX45208

The oil and gas industry has focused more and more on marginal and complex fields which often imply long offset distances and-or substantial water depth. The challenge is to develop technology-facilitating economic attractiveness of these fields. A large number of tools have been developed and offered to the market. Some of the tools requiring high-energy supply for operation are mentioned. All of these tools are designed to enhance oil and gas production but they still themselves require energy to operate and this energy has to be controlled very often by quite sophisticated techniques. Several investigations show that an electrical power supply system will be the most cost efficient solution for driving all the subsea processing pumps and other energy consuming systems at the seabed. There are two possible main concepts. The first is based on a topside electrical power distribution system where each subsea consumer is fed by a separate power umbilical from the host facility. The second has a supply cable and local subsea power distribution called SEPDIS (subsea electrical power distribution system). The system is described together with its control and monitoring system. It is concluded that all of the components required to construct the control and monitoring system for SEPDIS are proven and available with only detailed electrical engineering required to configure the hardware. One issue would be packaging of the SDU where the desire is to make the pressure-isolating vessel as small and light as the internal components allow but the design muX39187 Integrated control system for ship motion in inland navigation

URASHIMA a deep and long cruising range AUV is presented. This AUV has been developed by JAMSTEC since 1998. It can cruise long distances and can collect sea data and water samples automatically for offshore exploration. URASHIMA is outlined and descriptions of its power source navigation sensors and experimental results are given. There are two very important key technologies for a long-cruising range AUV. The first technology is the power source. URASHIMA has two types of power source. One is a high capacity Lithium-ion rechargeable battery. The other is a solid Polymer Electrolyte Fuel Cell. With these power sources the vehicle is capable of performing long ranges missions. The estimated cruising ranges are about 100 km using battery and about 300 km using fuel cell (at three knots). The second technology is the navigation system. An AUV cruises independently without any communications between mother ship and vehicle. It is very important to know its present position and forward environment. URASHIMA has highly accurate navigation sensors - its INS (inertial navigation system) consists of three sets of Ring Laser Gyro and accelerometers OAS (obstacle avoidance sonar) DVL (Doppler velocity log) and acoustic homing sonar. Sea-going tests started in JuX28657 Key technology development of a high temperature gas turbine for an advanced combined cycle M Sato ; Y Kobayashi ; H Matsuzaki et al.

The US Navy stands at the brink of transition from traditional navigation with paper charts to computer-based electronic charting. NAVOCEANO (the Naval Oceanographic Office) is posed to support this transition with state-of-the-art survey platforms instrumentation and processing and chart production software. Recently NAVOCEANO completed hydrographic surveys in the US Pacific territories of Guam and Saipan in support of urgent Navy operational requirements. Survey operations data processing and validation and product production for these areas are discussed. The areas were surveyed by the airborne lidar SHOALS canning hydrographic operational airborne lidar survey) system the rapidly deployable FST (fleet survey team) and a new multi-purpose ship USNS SUMNER (T-AGS 61). Each survey system brought unique capabilities to the toolbox of surveying assets. Each survey system also brought unique challenges to the data validator and chart compiler with system errors that first had to be recognised causes determined and solutions found. It was fortunate that these three different collection platforms were able to work the same survey area allowing comparison of three different data sets and the discovery of potential systemic errors. The validation process is discussed which included a very thorough investigation of the error sources and the correction of data from all three systems and the production of both a paper Field Chart and DNC (digital nautical chart) libraries.

Maritime industry has a big opportunity to increase profits when implementing the new associated DNV survey arrangement machinery CM (condition monitoring) classification. There are however strategic considerations to make when introducing CM to a ship. CM has in the past been introduced on several hundred vessels with limited or no success. In most of these cases the CM tool has been purchased without considering the necessary change of the organisation onboard and the need for an organised knowledge transfer between crews. The maintenance strategy has to support the CM activity and the results from the program must be used to change the priority in the maintenance work. The instrumentation and software should be selected to carry out front line CM onboard the vessel and more complicated analyses should be implemented as second line only. The economical aspect of CM is covered together with the strategically important considerations and the link to the new DNV classification. It is shown that the CM strategy creates both profit and better return rates to a much larger degree than shown by traditional economic models. Instead of simply regarding maintenance as a cost factor to be kept as low as possible modern management can treat it as a means of realising the profit potential inherent in each vessel.

Compensated fuel-ballast systems are used by the US Navy in three of its combatant classes as well as in LHD 7 to maintain uniform trim and draft. In such ships when fuel is consumed it is replaced by seawater for ballast which is later discharged overboard during refuelling. The discharged compensating water may contain concentrations of (fuel) oil in excess of applicable environmental regulations because the high refuelling rates and internal structure within compensated fuel-ballast tanks promote fuel-water mixing and entrainment of fuel into the compensating water. In addition water hideout in which water remains trapped in tanks when refuelling is terminated reduces fuel capacity significantly. The US Navy has undertaken an extensive research and development effort at NSWCCD to assess the current performance of compensated systems during refuelling operations and to develop and propose improvements to their design which may be implemented in either existing or future ship classes. The CFD (computational fluid dynamics) analysis and one-eighth-scale physical model experimental efforts to assess the performance of the 'Arleigh Burke' (DDG 51) class of US Navy guided missile destroyer mid-group compensated fuel-ballast tank 5-300-2-F are described.