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Naval vessels are increasingly using IEPs (integrated electric power) systems to supply main propulsion and ship services and these are applied to most substantial benefit on vessels with highly variable mission cycles. Currently there is a drive towards the adoption of compact propulsion motors where for surface vessels the provision of a lower shaft-line height and thus lower rake angle results in higher propulsion efficiency whilst overall mass and volume savings translate to increased payload or fuel. These enhanced propulsion capabilities could offer opportunities to radically change the types and number of ships comprising the future fleet to reduce total ownership cost. This paper discusses the design and analysis of a 7.5 MW magnetically geared propulsion motor or PDD (pseudo direct-drive) for a naval main propulsion application. The drive-train comprises two motors mounted in tandem to produce 15 MW at less than 100 rpm within a specified maximum volume envelope of 3.5 m x 3.5 m x 6 m and with a maximum weight of 100 mt. It was found through the course of the design study that the resulting PDD could be realised in a 3.5 m x 3.5 m x 2.1 m volume with a mass of 53 mt with no trade-off in efficiency.

Once again there is interest in nuclear propulsion at sea. The debate over CO2, with the likely introduction of market based measures, cargo owners’ perceptions of CO2 and the rising cost of fuel oil is driving the interest in non fossil fuels. Whilst wind, solar and other alternative technologies can contribute to a percentage reduction in fossil fuel use at sea, there is no other current power source, other than nuclear power, capable of replacing fossil fuels. The interest in nuclear powered merchant vessels is such that Lloyd’s Register has decided that it needs to support ship owners and develop draft rules for nuclear powered ships. The regulation of today is very different to that of 30 – 40 years ago when Lloyd’s Register last had nuclear powered ship rules during the period 1966-1976. Hence the style and philosophy of today’s rules for nuclear powered vessels are likely to be quite different. Lloyd’s Register have published a number of papers during 2010 on the subject of nuclear powered merchant ships. References 1 & 2 explore the technology and the thorny issue of the perceived risks from nuclear power plant operation. This paper looks at some aspects of how the regulation of nuclear powered vessels might be achieved and the Classification rules that would be required to support their operation.

The recent development of miniature GPS (global positioning system) devices has provided a new observational window on mechanisms of bird navigation. GPS tracking was used to examine the homing paths of pigeons (Columba livia) released 20 times consecutively 25 km from the loft. By the end of the training phase the birds had developed highly stereotyped yet individually distinct routes home with detailed recapitulation evident at each stage of the journey. Following training birds also participated in a series of releases from novel sites at perpendicular distances of up to 3 km from their established routes. Results showed that subjects were attracted back to their established routes and recapitulated them from the point of contact. Naive conspecifics (yoked controls) released from the same off-route sites confirmed that the experienced birds' route choices were not influenced by constraints exerted by terrain features but that increased experience with the general area conferred a homing advantage in the form of more efficient flight tracks even from these novel sites. Patterns in the paths taken by experienced birds to rejoin their established routes are discussed with reference to navigational mechanisms used by homing pigeons in their familiar area. Methods used are described. Results are presented and discussed.

Conf held in Aberdeen 24 - 26 June 1986 Papers are The management of contractors requirements Designing subsea equipment for ROV intervention ROVs and moonpools - an operators viewpoint Using an ROV for simultaneous lay and burial of subsea umbilicals Measurement and analysis of hydrodynamics of ROVs tether cable An integrated approach to operations Planning and conducting combined diver/ROV operations Risk management and insurance for the under water contractor Making the ROV electrically safe - in and out of the water ROVs increase diver safety Improved efficiency and loss prevention through ROV simulation Operational limitations - training for offshore ROV employees ROV training and certification - their effects on technology transfer The application of ROVs to underwater welding repair tasks Dredging tools for ROVs An integrated approach to subsea intervention An integrated visual imaging system Optimisation of high performance subsea cleaning system A cable location and tracking system for Cirrus The hardware and software development of a fully adaptive ROV autopilot The development of a remotely operated crack inspection systems - ROCIS A free swimming ROV The evolution of rigworker ROV acoustic position reference system for hydro electric dam inspection Eastport international Air India salvage effort A novel approach to object classification for military requirements JASON - an integrated approach to ROV and control system design Some applications of ROVs in fisheries science A small lightweight ROV for studies under Arctic ice

The offshore industry is responsible for designing and building offshore production systems such as floating petroleum production units including riser systems. The necessity of developing a cost effective structure with a good compliance is of the utmost importance. Nowadays the hybrid riser system concept is considered an alternative system in ultra-deep water up to 3000 meters for offshore petroleum production. Compared to other systems the SSHR (self-standing hybrid riser) has proved itself to be to be a good alternative. The system is composed of three main components: a vertical riser connected to the seabed a subsurface buoy close to the sea surface and a flexible riser connecting the buoy to a floating production facility. Despite the good performance of the overall concept many problems still remain in the design of this type of riser system dealing with oil and gas production or exporting petroleum production. Here the dynamic behaviour of a vertical riser with a subsurface buoy near the sea surface is described. Hydrodynamic loads due to currents and waves in the direction of the loads and in the transverse direction due to vortex shedding are considered. Critical points are addressed throughout time domain calculations in terms of riser VIV (vortex induced vibration) and in-line motions due to current and waves. The influence of buoy oscillations on the riser behaviour is observed. For a first attempt of a developed model comparisons have been carried out with experimental results.

Brazilian oil and gas reserves are commonly located in deep and ultra-deep waters. In order to exploit these reserves oil companies must seek technically feasible and cost-effective solutions to the problems caused by deep and ultra-deep water depths. The use of TTR (top tensioned riser) with a floating vessel such as a TLP (tension leg platform) and spar buoys is an attractive solution because this kind of platform allows dry completion reducing operational costs. A brief introduction of the fundamentals of TTR dynamic behaviour is presented along with service life estimation using numerical simulations in time domain. The simulation of riser motions due to environmental loads ocean waves and marine current was carried out along with bending moment and stresses. In-line and transverse riser behaviour is also be considered. VIV (vortex-induced vibration) in risers due to waves and current is modelled. Riser service life calculations are shown with and without the influence of VIV. Lateral motions and offset at the top of the riser due to the surface floating production unit also are considered in the simulation. Time series from numerical simulations are presented for different environmental conditions with explanation regarding the impact on riser service life.

Symp held in Rotterdam 6 - 10 Sept 1982 Papers are Ship/harbours - a ship operators view Port and economics Port approaches and terminals The integration of engineering practice and science in cargo handling Required underkeel clearance in ports Transport systems and their operators in times of change Port development - to lead or to follow? Decision supporting systems - function of a port terminal operator Next generation of energy carriers Characteristics of new coal fired bauxite carriers A new breed of VLCC - the very large container carrier Tanjong Pagar container terinal of PSA - a pivotal port in South East Asia Tankers and single point moorings The mooring of ships - from skill to science The process of designing North Sea highways Vessel traffic guidance an industrial view Accident analysis - a tool for a safer maritime community The Louisiana offshore oil port Offshore coal transhipment Barge transport - some aspects of an inland transport system New developments in inland shipping The dynamic growth of technology in the barge industry of the US western rivers and future trends Social organisational considerations for the design and functioning of future ships Ship automation systems of the eighties Maintenance policies Noise and vibration annoyance on board ships The port of the future - policy and control The maritime future - the importance of a free market Research supporting maritime operations in the 2000s

Semn held in Hamburg April 18 - 21 1978 Papers are The European ship repai r industry - current status and future prospects Ship operators view of repair facility requirements Hull loss prevention and mitigation Technology and ship operation En voyage repair and retrofits - the operators viewpoint Progress in classification society survey techniques Corrosion control Retrofitting vessels to comply with inevitable legislation Assessing and planning for drydocking requirements of a mixed tonnage fleet In water survey and afloat maintenance from the operators point of view In water maintenance - a classification society view point In water surveys maintenance and repair - the state of the art Application of low quality fuels in large bore diesel engines Aspects for future bunker fuels and their influence on engine performance Lubrication efficiency as means of reducing operation and maintenance cost Microbial infection of ships lubricants Control systems - availability maintenance and repair Monitoring and diagnostic system for four stroke diesel engines A look ahead in turbine maintenance Marine fuels and lubricants - towards 1990 Spares selection and procurement viewpoint from a ship operator Spares selection and procurement - viewpoint from original spares suppliers - viewpoint from "open market" spares supplier

Oyster harvests from Mississippi reefs provide jobs for numerous fishermen and contribute substantially to the economy. Proper management of these reefs is vital for continued harvest. Enhancement management techniques (i.e. cultch planting and-or cultivation) should help ensure even greater future production. Cultch planting is a key component of management measures carried out by MDMR (the Mississippi Department of Marine Resources). Cultch plants are typically evaluated with sounding poles tongs dredges or scuba equipment. These methods are not very efficient when surveying large areas for coverage rates or distribution of materials. The use of side scan sonar to monitor cultch plants has a number of advantages over these methods. Side scan sonar can cover large areas in less time provide accurate measurements of coverage and simultaneously provide differential GPS coordinates. Information acquired from side scan sonar provides a long-term record which can be used to detect changes due to environmental catastrophes vessel groundings and-or harvest pressure. A side scan sonar survey was carried out before cultch planting on the St Joseph cultch plant site located in the western MS Sound. The side scan sonar was also used to evaluate two barge groundings sites. The data was processed and input to a mosaic software program for further analysis. The abilities of side scan sonar as a tool for oyster reef management are shown. Results are presented followed by some discussion.

The use of highly flexible risers for oil drilling purposes is widespread. In terms of simple modelling a freely hanging riser with minimal bending stiffness can be considered as a catenary. However it is common practice to incorporate a buoyant portion relatively close to the seabed and this results in the standard configurations of lazy wave steep wave lazy-S and steep-S according to whether the riser rests along the seabed and the means by which the buoyancy is achieved. Furthermore it is reasonable to assume that the riser possesses some bending stiffness. These factors conspire to make the static and dynamic analysis of risers somewhat challenging. Here flexible risers and pipelines are modelled as slender elastica structures. The theoretical formulation leads to a type of non-linear boundary value problem that can be solved numerically given appropriate boundary conditions. The offsetting effects of gravity and buoyancy are included in the analysis. These forces can provide considerable axial loading (as can thermal changes) and hence stability (buckling) is a major concern. Initial studies are based on the planar problem. A free-vibration analysis is also conducted for small-amplitude oscillations about various deflected equilibrium configurations in terms of natural frequencies and corresponding mode shapes. Energy dissipation and fluid forces are a key issue in the forced problem especially when large deformations are involved. Free vibration information is a vital prerequisite in understanding the response of these types of structures in practice.

NDBC (The National Data Buoy Centre) operates numerous instrumented marine buoys measuring oceanic and atmospheric environmental conditions around the world. Currently buoy environmental monitoring payloads use all available power. Future buoy upgrade options will require an increase in buoy power system capability. Reductions in future buoy power system maintenance requirements are also desirable. The environmental conditions experienced by buoys located in high-latitude locations severely limit the power output of current buoy power systems which are based on conventional silicon-based photovoltaic cells and sealed lead-acid batteries. Science Applications International Corporation recently carried out a top-level system engineering design study to identify realistic near-term cost-effective design options to meet emerging power system requirements for NDBC buoys particularly in challenging high-latitude environments. The study identified requirements design drivers and operational issues as well as examining potential power system upgrade solutions using aerospace-type technologies. The study found that increases in power output and energy storage capability were indeed possible by using near-term alternative technology. A Ni-Cd battery based system was identified that could increase power capability and require less maintenance support. Proposals are presented for additional design study and supporting activities that may have additional potential to address this difficult issue.

While a significant amount of research over the past 30 years has been carried out on the structural response of ships due to collisions it has only been in the past 15 years or so that structural damage due to ship grounding accidents has been investigated. Early work in ground prediction involved performing plate-cutting experiments which produced empirical formulas for the work to cut a flat plate. More recently studies of the kinematics of plate cutting have resulted in closed-form expressions for upper-bound solutions for the plate-cutting force required to cut a single plate but do not account for the effects of stiffeners and inner hull that exist in the actual geometry of ships. In order to adequately predict the resistance forces in a ship undergoing a grounding accident and the subsequent extent of damage further research is required to account for the interaction of ship structural members one with another. The cutting by a wedge of ADH (advanced double hull) small-scale models is studied. A total of six cutting experiments were carried out with six different wedge geometries. Complex deformation patterns observed in the damaged specimens were simplified to obtain a closed-form upper bound for the steady-state cutting force. The ADH steady-state cutting force solution varies from 6 per cent above to 12 per cent below the experimental mean steady-state force. The absolute average error is 5 per cent.

Would the day after dredging stopped mark the onset of a world without sediment plumes? To answer this question it is necessary to consider a wider range of natural and man-induced drivers of sediment plumes in delta areas. Would shipping activities cease the day after we stop dredging? Certainly not. Also would natural rivers stop discharging large quantities of fine sediment during periods of high water run-off? Again the answer is no. To assess the environmental benefits of an idyllic world without dredging it is necessary to evaluate the impact of maintenance dredging activities as compared to the impact of other ongoing drivers of sediment plumes. This paper presents recent progress in the framework of the TASS (Turbidity Assessment Software) program which aims at the development of a validated model to predict dredging-induced turbidity levels. A key component of this program is the execution of a series of large scale field trials to collect high-quality data that can be used for model validation purposes. Although the TASS program focusses on dredging-induced turbidity increases it should be noted that dredging is just one out of a series of processes that drive sediment plumes including natural events shipping operations and fishing activities. An inventory of these processes suggests at least qualitatively that the annual impact of these processes is of the same order of magnitude as dredging. Consequently it can be concluded that the day after we stop dredging will by no means mark the onset of a world wit101513

Some test work is presented which was carried out in collaboration with a leading pump manufacturer in Denmark in February-March 2001. The main aim of the work was to test means of increasing the operational efficiency when transferring highly viscous oil (refloated bitumen). The main differences compared to earlier work are twofold: firstly the viscosity of the oil was considerably higher than in previous reported tests; secondly the effects of water lubrication were evaluated at both the pump outlet and the inlet which is in contrast to earlier work where these variables were only evaluated at the pump outlet. The tests showed that steam-hot water injection at the inlet flange of a positive displacement Archimedes screw pump greatly increased the bitumen transfer rate. Thus it could be concluded that by the implementation of relatively simple means a large number of mechanical feeder skimmers with an onboard high viscosity transfer pump have the potential to recover and transfer highly viscous oils. The extreme viscosity transfer technique based on steam-hot water injection via an injection flange specially designed for the inlet of the transfer pump could be a useful tool in several other types of operation. Emergency pump transfer of oil under arctic conditions and emergency pump transfer of cold bunker C from sunken vessels are obvious examples.

The Jinan Diesel Engine Company has been manufacturing diesel and gas engines in China since 1920. The leading product 'Chidong'series 190 diesel engine is the main power in China's petroleum industry. Many of these engines power oil and gas drilling rigs. A new 12V190 Jinan Diesel engine has been designed and developed to meet the needs of the Chinese market for a modern versatile engine for marine propulsion power generation and locomotive applications. The engine components and the performance and the durability of the engine are described. Emphasis was put on the development of the turbocharger to suit predominately three applications: constant speed operation for power generation; variable engine speed for marine propulsion; and the high torque backup for the drilling rig drive application. The acceptance test results showed that all performance development targets were either reached or with regard to fuel consumption and emissions were even significantly below the values agreed at the beginning of the development. The performance is considerably better than that of most of its domestic competitors and the first commercial production version is now in service. The combination of good performance and competitive manufacturing cost is likely to make it a success. An essential part of the project was the transfer of technology to JDEC and the requirement to source as many parts as possible locally in China. Development tests were started in Austria and continued in China. The steps in this process are explained. As is usually the case withX16514 The new 280mm bore engine from SWD

Engineering university accreditation boards around the world have recognised the need for a balance in theory and practice. In the past 10 years there has been a strong resurgence of interest in design experience and teamwork. This is provided in student team-based projects. Student design competitions have been developed as an integral part of this approach. Although the benefits of such competitions are clear in the teaching of marine design in some ways these competitions can be viewed as controversial. SNAME (the US Society of Navy Architects and Marine Engineers) runs a number of annual student marine design competitions with international entries. SNAME's education committee recently formed an Ad Hoc Group to look into all aspects of the design competition organisation and conduct. It has developed a series of recommendations for SNAME for the future of the competitions. A major focus of the review has been on how the competitions can be made better for the students. The benefits of design competitions as an aid to teaching design are discussed. A brief history of the competitions is given and the findings and recommendations of the Ad Hoc Group are described. Conclusions are drawn.

A 'state of art' in the development of the time domain dynamic simulation of 3D bending hysteresis behaviour of a flexible riser under offshore environment loading is presented. The main technical challenge is to understand and model the riser tensile armour behaviour under continuous changes in both the magnitude and direction of bending and its subsequent impact on the riser's bending hysteresis characteristics. Because of this technical obstacle the current industry practice is to model the riser as a linear structure with certain conservatism enforced and then to extract the global dynamic loads to a detailed local model for stress and life assessment. Two 3D flexible riser bending hysteresis models are introduced that were developed by Wellstream and Orcina respectively. Also presented are their calibrations against the bending hysteresis loops measured in full-scale tests. Both models are implemented using the analysis program OrcaFlex; the Wellstream model is a detailed model that calculates both the total bending moment and the stresses in the tensile armour; the Orcina model is a simpler model that only calculates the total bending moment. A study is presented to illustrate the difference in the riser dynamic responses with and without consideration of the bending hysteresis behaviour and to assess the difference in the dynamic responses between the Wellstream and Orcina 3D bending hysteresis models. This development permits more realistic riser structural properties to be modelled in the dynamic simulation and reports detailed time history stress or strain resultX39366 Time Domain Simulation of Vertical Ship Motions and Loads in Regular Head Seas

World trade is dependent upon transport and transportation capacity and great strides have been made in the last 10 years to render this system open frictionless and as secure as possible in order to encourage even greater economic growth but the risks in transport are still numerous and they are present in every type of transportation. Slovenian companies today are doing more and business than ever both nationally and internationally. Whatever means companies chose to move their goods around they do have a need for cargo insurance. Those who are responsible for the goods entrusted to them (such as freight forwarders logistic providers carriers etc) have their liability regulated by national and international legislation and conventions. Liability in the different forms of transportation and at different stages of cargo handing varies. There are a number of insurance solutions depending on the nature of the activity being undertaken. Security of a product in transit is an absolute necessity but security means much more than physical protection. It also involves risk management and procedural control. Historically anyone who has an insurable interest in a cargo shipment has need for cargo policy. This field of insurance protection is explored the types of policy are considered as well as the various types of liability.

During the past year 'LNGbySea' has been developing a new truly modular system for the water-borne transportation of LNG. The system is called the LNG CyroTrain (LNG SeaTrain) and represents a significant change from the traditional LNG tanker. It offers the benefit of supplementary shore-side storage capacity the ability to have multiple as well as more remote terminal locations the ability to access river-based supply and delivery terminals in the inland waterways of the US as well as key rivers of the Amazon and Yangtze. It also makes it possible to operate economically on shorter multiple-delivery routes within such places as the Caribbean Basin. The system is a truly modular one consisting of a high-speed delivery vessel called the Mothership and a number of barge-style tanks or cargo containers called LNG CyroBarges. These can either be filled or off-loaded while aboard the Mothership or easily floated off the Mothership and left at any of the transport terminals for more timely loading or discharge schedules. One Mothership can carry three or four such CyroBarges increasing the per voyage transport capacity. Both Mothership and LNG CyroBarge have received preliminary approvals from ABS and the US Coast Guard. The construction time is substantially reduced and can be built and delivered in 12-18 months. The concept is described together with its advantages.

HF coastal ocean radars are ideal instruments for the detection of surface currents in coastal waters and have had a wide application for monitoring tidal and wind driven surface currents. This paper addresses the easier question of how best to detect a tsunami in the water after its has been formed. The questions of spatial and temporal scales are addressed for optimal detection of tsunami properties by HF radar at the shelf break and on the continental shelf itself. Two approaches are used in this evaluation. The first is a stylised tsunami wave approaching a shelf which has parallel bathymetry contours and a shelf with uniform depth. In this case the non-linear effects at the edge of the shelf are the same at all points along the shelf edge and the subsequent wave train emerging onto the shelf has parallel wave fronts. The second approach is a case study of a real section of shelf-edge and shelf bathymetry. In this case numerical modelling indicates that there is a complex pattern of surface currents at the shelf break which varies in space and time. The subsequent wave train has a complex wave front which can be considered to be generated from point sources along the shelf edge. These wave fronts are shaped by local shelf bathymetry as well as interference of waves from the originating source points at the shelf edge.