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The stability of ships and ocean vehicles in waves may be quantified by a transient capsize diagram which is a plot of wave period against wave steepness showing the combinations which cause capsize. It is argued that a plot of wave steepness against wave period showing the combinations which cause capsize is a well-defined measure of the stability of a ship or ocean vehicle in waves provided the conditions are transient that is the vessel is initially in relatively calm water and is suddenly hit by a train of regular waves. This conclusion is a consequence of recent developments in dynamic systems theory. Such transient capsize diagrams can obviously be obtained by model testing; it is also argued that they could be obtained by computer simulation on contemporary desktop computers taking advantage of recent developments in non-linear strip theory.

Normal density and lightweight high strength concretes result in durable structures with reduced floating drafts. Higher strengths are nearly always achieved using silica fume as a supplementary cementing material. However those with silica fume show a continual reduction in strength under fire loadings and have been shown to fracture at temperatures of less than 300 degrees centigrade. On the other hand those concretes without silica fume often recover their initial loss of strength at temperatures of around 300-400 degrees centigrade. The moduli of elasticity of silica fume concretes determined under static state fire loads can lead to the inaccurate location of plastic hinges. Polypropylene fibres within the concrete produce specimens that remain undamaged visually but that have significant internal damage to their residual strength. Solutions to these difficulties are discussed and include polypropylene fibres passive fire protection systems and the use of a sacrificial cover layer of concrete. The limitations of existing work are described.

Classification as a process began in the late 1700s when merchants required assurance about the standard of vessels in which they were shipping their cargo. The use of the Classification process by navies can be traced back to 1859. However it is only recently from about 1980 that we have seen the UK Navy make use of the commercial Classification process on ships. In the 1990s Classification Societies developed specific Naval Classification standards and processes. Classification Society Naval Rules and procedures have been applied in UK Naval platform procurement for the last six years. Class societies have found themselves trying to satisfy the conflicting needs of the naval operation naval regulator prime contractor system designer equipment supplier and even their own organisations. This paper aims to capture some of Lloyd's Register experience in a form that can be applied to the benefit of future projects. It covers a subject not normally addressed which is how to best use the Classification process to achieve an effective and affordable warship.

There is a legal requirement to establish Safety Integrity Levels (SILs) in terms of hazard and consequence in the design of offshore installations. A methodology that provides consistent auditable results is therefore needed. Such a methodology has been developed and tested on three offshore installations including an FPSO. It uses data from the installation quantified risk assessment (QRA) to determine the SILs for the control loops of process control hazard monitoring and shutdown systems. A combination of event and fault trees are used to assess the contribution of a specific system to the annual fatality rate (AFR) for a range of hazardous events. Generic models have been developed to enable SIL levels to be determined where QRA data is unavailable.

The investigation of wreck sites is of great interest to archaeologists. However this often needs to be carried out within a limited budget. Often the task is time-consuming as a result of the wreck being poorly defined or buried in the sediment with little surface location indication. The relative value of magnetometers sidescan sonar sub-bottom profilers and swathe bathymetric systems in offering assistance to the diver within their initial searches and with an appraisal of the extent of the heritage site is examined. The activities over two wreck sites are examined. Conclusions are drawn on the effectiveness of the sensors used the benefits of an integrated approach and the potential offered by alternatives such as the emerging technologies offered by swathe bathymetry systems is reviewed.

Total Quality Management (TQM) is a tool for developing environmental programmes to control corporate environmental exposures. It embodies principles of policy delineation operations accountability documentation and review. Air quality is used as an example to highlight the application of TQM methods for safe and effective environmental management of passenger ships. Based on analysis policy decisions can be made as to how to best operate the fleet or an individual ship in a cost effective manner yet allowing it to operate within the constraints of environmental conditions. Once policies are established written fleet directives are then developed which will serve as a benchmark for the future ship audits. As conditions change the TQM process provides ships with a formal method to inform shoreside staff when compliance may not be possible due to operational difficulties. Once directives and training are in place the ship is periodically and systematically audited to assure compliance with policies and directives.

The non-linear shallow water equations (NLSWE) model has been used in engineering practice as a computationally inexpensive tool to quantify wave runup reflection and overtopping at seawalls. However there is a growing concern about the mathematical limitation of the NLSWE model. Theoretical results and experimental data are used to test and expose the weakness of the model under typical design conditions. The validity tests are focused on two basic types of seawalls -simply sloped and vertical seawalls and testing waves conditions are grouped into four - reflecting and impacting steep and mild waves. The results demonstrate that the model is capable of simulating wave runup and flections of the mild and reflecting waves and that care is needed for impacting and steep waves. The results show that the NLSWE model has some tolerance to the violation of the shallow water assumption but less for wave breaking. Validity quadrants for modelling wave runup and reflection are suggested.

The effects of innovations in roro vessels and development of high speed craft on ports as a link in the roro transport chain are discussed. It is concluded that the integrated design of the ship to shore interface will be achieved more successfully by communication between naval architects ship equipment designers port engineers shore ramp designers passenger walkway designers and ships' masters. Such communication should be encouraged at an early stage in development plan for a new ferry or terminal to improve efficiency of roro operations.

A cross-sectoral Ocean Council is now being established to bring together and work with the diverse ocean business community operating in the global marine environment e.g. oil and gas shipping ports fisheries aquaculture etc. This creates the opportunity for business and industry to interact in a more coordinated comprehensive way to address Corporate Ocean Responsibility i.e. operating sustainably in the shared global ocean ecosystem. For young ocean entrepreneurs the Ocean Council provides the means and opportunity to help ensure a sustainable future for the oceans through participation in a global network of private sector leaders from the ocean business community. After some introductory information a look is taken at the global ocean - global industries - global impacts on the marine environment. Next attention is given to the rules that rule the oceans and the tragedy of the ocean commons. Lastly

The WR-21 is an advanced cycle gas turbine system developed specifically to power the next generation of warships. Its technical features are described concentrating on those elements that foster its unique efficiency characteristics. For these components the various test methods used to aid the design are detailed. The structure of the development test programme is described showing how it was structured to reduce risk and also how Navy requirements have been considered in specific elements of the test programme. The qualification strategy is detailed and illustration is given of how the testing is structured to address typical service operational issues. The immediate future for the WR-21 in naval operation is considered highlighting the operational benefits gained from the integrated collaborative approach to the development and qualification test programmes.

Subsea production of oil and gas involves structures on the seabed such as manifolds and Xmas trees that require thermal insulation of piping and valves to avoid gas hydrate formation. The insulation is expensive and time consuming to apply yet may still leave areas with inadequate protection. These "cold spots" accelerate the cooling during a production shutdown. A Heat-Bank concept is developed as an alternative to conventional insulation. The entire subsea structure is covered with an insulated shell. During shutdowns the heated fluid inside the cover keeps the production equipment warm over a prolonged period before hydrates start to form. Computational Fluid Dynamics (CFD) simulations are used to quantify the heat loss effects of natural convection and leakage through openings in the cover. The CFD analyses demonstrate the relative performance of the concept compared to the traditional method of insulating individual piping components. Application of the Heat-Bank concept opens new possibilities for environmentally friendly and cost-effective field development especially for deep water.

Latent heat recovery from the flue gas is very important in order to improve the efficiency of a boiler or thermal plant. Condensation heat transfer on horizontal spirally finned tubes of fin pitch 5 mm and 10 mm is investigated using an actual flue gas from a natural gas boiler. Experiments are conducted at different steam mass concentrations of the flue gas and a wide range of tube wall temperatures. Thermal-hydraulic behaviour of the economiser for the latent heat recovery is also investigated using an actual flue gas from a propane gas fuel boiler. Experiments are described and results are presented and discussed.

The intention of this paper is to develop a numerical model to simulate the thermo-mechanical buckling phenomenon of buried heated pipelines in shore approach areas. Furthermore a sensibility analysis adopting geometrical physical and operational data is carried out for a particular Petrobras project. The in situ geophysical survey geotechnical and oceanographic information are also taken into account. The influence of the sediment transport after opening the trench and required backfilling with a heavier soil is also addressed. This paper focuses on the challenges for the design and installation group due to the burial requirements in order to find a safe solution for the burying process by trenching and backfilling known methods.

Direct numerical simulations of the three-dimensional flow around an oscillating circular cylinder are carried out. Imposed body oscillations are realized for low amplitude of oscillation A/D = 0.4 and for high amplitudes A/D = 1.0. As the intention is to analyze the amplitude influence in the wake dynamics the frequency of oscillation is fixed and chosen to be inside the lock-in region 0.95 fS where fS is the shedding frequency of fixed cylinder. The three-dimensional wake characteristics of the oscillatory body simulations are compared to the fixed body. Floquet stability analysis of two-dimensional oscillatory flow is carried out to complete the investigation and consistently analyze the three-dimensional flow results. The different unstable modes are identified for each of the cases and they are found to depend basically on the vortex patterns.

This volume deals with the subject of dies, both forging and punch press, the design of gages for interchangeable manufacture, the limit system, modern drafting room practice, elementary pattern work, feeds and speeds and cutting lubricants; thus covering broadly the entire field as required by the modern tool engineer. Particular attention has been given to the chapters on die design. Contents include: Design of drop forging dies; Design of cutting and shaping dies; Progressive blanking dies; Design of piercing dies; Design of drawing dies; Compound dies, their principles and advantages; Design of gages; Design of reference and work gages; Inspection gages; Gaging screw threads; Cutting lubricants and their application; Speeds and feeds of machine tools; Pattern work and its relation to the designer; Organisation of the tool drafting department.

Scale models of the ocean bottom exhibiting multiscale roughness having power-law form power-spectral density are useful for validation of deterministic and stochastic rough-surface scattering theories. Such scattering theories require accurate knowledge of the topography of the scale-model surface which at acoustic scales can be measured on a two-dimensional grid using a kinematic-resistive touch-trigger probe and represented by a digital elevation model. Both the discrete representation and the physical measurement process introduce spectral artifacts. Here a numerical model of the physical measurement process is presented which is used to simulate spectral effects of probe measurement.

This paper describes the experimental work carried out to validate the Sea Snail postulate; that a tandem hydrofoil array can be used to secure a static device in a vigorous flow. The supporting theory related to Low Aspect Ratio (LAR) hydrofoils with end plates is given in the context of flow over NACA0013 hydrofoils. The experimental procedure is outlined and the statistical analysis of the results shows a good correlation with confidence levels associated with a normal distribution curve. The experimental results are plotted and the behaviour of the hydrofoils is described at each test velocity from 1m/s up to 3m/s. The effect of the wake from the leading hydrofoil on the intermediate hydrofoil and the sudden stall of the latter at flows exceeding 2.5m/s

ACOMMS (underwater acoustic communications) are useful for many practical applications. This paper addresses the technical challenges and approaches for semi-continuous underwater acoustic communications i.e. transmission of long packets under different environmental conditions without periodic training. The packet length is normally constrained by the channel coherence time for a given bandwidth beyond which channel tracking using an adaptive decision feedback equaliser becomes difficult. However if the channel is known for each block of coherence time communications can proceed in principle continuously without time limitation. Using the iterative correlation-based equaliser where decision symbols are assumed to be the true symbols to estimate the channel condition it is shown based on at-sea data that long packets of data can be transmitted with minimal errors even in harsh environments where the channel coherence time is very short (a fraction of the packet length).

Techniques of generating short crested waves with arbitrary directional spectra have been developed. This paper reports on ship motion tests in towed condition (Froude numbers are 0.2 and 0.275) in a long tank by generating uniform irregular waves with arbitrary directional wave spectra and describes the comparison between analyzed and theoretically estimated results. The compared results show a relatively good agreement. For the analysis of directional wave spectrum the Maximum Likelihood Method was adopted. Theoretical estimation is made by using analyzed directional wave spectra as input wave and also using directional motion transfer functions calculated by the New Strip Method.

This major revision updates and expands the popular databook for engineers and technicians working with machinery for process, oil and gas, utility and marine service. Representing the accumulated knowledge of the Transamerica Delaval engineering staff, this authoritative handbook covers the design, operation and maintenance of a variety of industrial products and equipment - turbines, pumps, engines, compressors, gears, condensers and filters. Emphasis throughout is on usable and practical information, and only a minimum of theory is included. The introductory section contains conversion tables, mechanical and physical data, fluids engineering data, and basic engineering principles relating to mechanics, heat transfer, thermodynamics and fluid mechanics. The other sections cover mechanical and physical data, fluids engineering data, basic engineering principles, turbines, gas and oil engines, marine propulsion systems, pumps, compressors, power transmission, steam condensers, filtration systems, test instrumentation and switches.