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The hydrodynamic performance evaluation of ships is crucial in ship design. Today CFD (Computational Fluid Dynamics) and EFD (Experimental Fluid Dynamics) are being used by designers in a mutually complimentary manner to predict hydrodynamic performance. Initially the area of CFD applications was restricted to resistance and self-propulsion evaluations in a model scale. However as available computer resources increase broader ranges are being covered by CFD including manoeuvring simulations full-scale evaluations and so forth. In this paper various CFD applications for hydrodynamic performance evaluations of ships are presented which demonstrate the capability of two state-of-the-art RANS (Reynolds Averaged Navier-Stokes) equations solvers being developed at the National Maritime Research Institute. The self-propulsion performance of a ship in a full scale is evaluated in the first application. Propeller effects are taken into account with a body force model based on a simplified propeller theory. This simulation provides information on scale effects which is difficult to obtain by EFD. Manoeuvring performance evaluations are important from the safety point of view. CFD applications to manoeuvring problems are carried out for the dynamic PMM (Planar Motion Mechanism) cases as the second application. In order to estimate wave-making resistance of a ship accurately the ship's trim and sinkage must be taken into account. The third application is concerned wX19836

SHIPS: FROM THE ARCHIVES OF HARLAND AND WOLFF - THE BUILDERS OF THE TITANIC Taken from the archives of Harland and Wolff, one of the world's most enduring and respected shipbuilding companies, SHIPS presents a selection of elegant designs. During an era in which steam propulsion was still in its infancy, many of these historic illustrations depict the tentative crossover to the new technology, incoporating the fine lines and slender hull shape of the traditional sailing vessel with the power of the new engines. While steam was intended to be the main source of motive power, the addition of sails provided an alternative and trusted method of propulsion should this "new-fangled" steam engine fail to live up to its expectations. Edwin Harland was known in his day as an innovative and daring ship designer and his flair for elegance as well as strength is apparent throughout this riveting history. The construction of these ships provides as much in the way of safety, utility and comfort as it does to aesthetics. This unique account is both a fascinating and historic document and a superb expression of the shipbuilder's love of seagoing craft, and his exquisite skill in designing such refined ships to the most precise specifications. Lavishly illustrated, this highly informative work contains over 175 color illustrations.

The offshore pipeline industry has developed greatly over recent decades. Its improvement in performance is due in the main to the construction of unburied pipelines. However this method is subject to a number of problems. The freespan that appears as a consequence of uneven seabed and local scouring threatens the total safety of the pipeline by creating a cyclic loading due to the VIV (vortex shedding induced vibration). The VIV cyclic loading can cause fatigue damage hence the fatigue strength of the pipeline needs to be calculated. In general the Morison equation is used for estimating the averaged hydrodynamic force acting on an offshore structure. However to elaborate the vibration forces due to VIV effects simulation of the vortex shedding and its induced time-dependent pressure and velocity distribution is very essential. A numerical is presented which simulates the VIV effects of the offshore pipelines by calculating numerically the vortex shedding and its induced turbulent pressure and velocity field. Finally the unsteady pattern of dynamic drag force is obtained by the model which is constructed based on the RANS (Reynolds-averaged Navier Stokes) equations in conjunction with a standard k-e turbulence model for turbulence closure. The unsteady pattern of dynamic drag force is obtained for current condition to simulate the VIV effects. This pattern is important for two reasons: firstly the governing equation of pipeline would be solved as a general beam equation; and secondly the frequency of the flow-induced vortex shedding can be defined exactly.

The USCG (Coast Guard) is currently complying with the International Convention for Prevention of Pollution from Ships (Marpol 73-78) Annex 5. The CG carefully evaluated the needs of its major cutters the equipment market search and an EA (environmental assessment) of the proposed alternatives before choosing marine incinerators as the primary alternative for safe disposal of solid and plastic waste onboard its major cutters. The type of marine incinerator chosen not only handles solid and plastic waste but can also burn waste oil and oily waste thus the CG avoids the segregation of plastic from food waste and also saves the cost of disposing of the waste oil. On smaller cutters where an incinerator cannot be retrofitted the CG has opted to install compactors and pulpers to handle the solid waste. The CG's solid and plastic waste management program its status success and recommendations are briefly described. The CG did not follow the Navy's design of solid and plastic waste handling equipment but rather considered the specific needs of its own cutters. The prototype incinerators were installed and tested by the Navy's environmental team and it was determined that they were complying with applicable IMO and US environmental laws and regulations meeting health and safety requirements and supporting the USCG mission.

Commercial fishing in the US has the worst safety track record of the major industrial occupations. It is currently experiencing casualties at a rate of seven times the national average for all industries; over 40 per cent of these losses are stability-related. A number of attempts have been made recently to reduce these casualties and to help resolve associated liability concerns. The absence of Federal regulation and the absence of licensing and qualification requirements place the skipper himself at the centre of any hope for improvement. To help him the engineering community can develop and provide better guidance for the safe operation of his vessel. Two means for better guidance are proposed. These are based on roll motion limits using the one stability attribute a skipper can sense and better visual images of stability. First the causes of past problems in reliably relating roll period and metacentric height (GM) are exposed and the 'missing piece of the puzzle' is provided. As a result a simplified method of stability assessment via the roll test is proposed. The method is shown based on test results to be highly reliable. Secondly innovative ways of presenting stability characteristics to fishing vessel operators are proposed in the form of visual images and models which are intuitively better appreciated by non-engineers than displays currently in use such as the righting arm curve.

When the International Convention on Load Lines was being written a decision was made not to cover yachts when used for pleasure. However a yacht is no longer solely a pleasure craft not engaged in trade. It has to earn its keep and is now frequently "engaged in trade" albeit to a small charter party or group of friends. Therefore strictly speaking the full requirements of the load line convention are applicable but they just do not work. Many yacht designers have problems meeting the requirements of any of the rules or regulations. In response to this the United Kingdom Maritime and Coastguard Agency developed "The Code of Practice for the Safety of Large Commercial Sailing and Motor Vessels" (LY1) which was later developed into "The Large Commercial Yacht Code" (LY2) both of which have been declared as equivalent to the load line convention. The Lloyd's Register's Special Service Craft Rules (SSC Rules) also contain requirements for items that are covered by the load line convention and some relaxations from the convention are allowed. In this paper a summary of the differences between the various requirements is presented together with flow charts to show which regulations are applicable to any particular vessel. Various alternative means have been found to achieve compliance and this paper describes what has been accepted and the reasoning behind the acceptance. Ths paper also addresses some of the issues that frequently arise when calculating freeboards for yachts.

Ozone has an important but as yet largely unrealised and unfulfilled role to play in reducing environmental damage to marine ecosystems as well as improving the onboard environment and living conditions for all shipboard personnel. Ozone can provide pure and safe potable water that is critical to vessel safety as pure water has an immediate impact on the health and morale of both crew and passengers. Ozone can also be the central player to eliminate chlorine in the purification of sewage in a new type of MSD. Controlling the spread of non-indigenous invasive species transported in ballast water is another beneficial and potentially valuable application of ozone. Apart from some R&D installations the only one of the three applications listed that is presently in real time use is the purification of potable water within the holding tanks on board two US Navy vessels (RV KNORR and RV ATLANTIS) and two National Science Foundation vessels (RV OCEANUS and RV ENDEAVOR) as well as several luxury yachts. Woods Hole Oceanographic Institution operates the three former vessels and the University of Rhode Island Graduate School of Oceanography the latter. Ozone is also being used on board over 250 yachts from 31 ft. to over 300 ft. including power and sail for indoor air quality and odour control as well as odour control in the headspace of black and gray water holding tanks.

Titanium catenary riser solutions for gas export have been developed for the Asgard B and Kristin semi-submersible platforms in the North Sea. The large wave motions and offsets caused by the weather conditions require significant flexibility of the risers to avoid fatigue and extreme load damage. The concept for a 28-inch titanium riser designed in 1999 for Asgard B has been improved and verified and a solution with two parallel 14-inch titanium risers has been developed for the Kristin platform. The concept has undergone a stringent technology qualification process based on a new procedure established by DNV. It is concluded that it is feasible to install titanium risers on semi-submersible platforms in North Sea environment. One of the most critical issues for the qualification is to ensure that the manufacture and fabrication of about 800 m long risers can be done with the required material quality weld properties and dimensional tolerances. Hence full-scale samples have been manufactured welded and tested to evaluate the properties of the final product. In particular the fatigue capacity and associated quality control procedures were considered. The riser pipe was considered fit for the purpose. Another critical issue was the design of the riser configuration and hang-off arrangement. Both extreme load conditions at the extreme offset conditions as well as the fatigue load effect were critical failure modes. Sufficient safety margins were obtained for different combinations of the design parameters andX13216 Titanium in industry

Surveys aiming to isolate the main causes of severe marine diesel engine damages clearly indicate the need for a reliable method to carry out real time monitoring of crank pin and big end bearing temperatures in large diesel engines. This would reduce the risk the risk of high-cost damage and thus increase the overall level of safety at sea. However both the hostile environment inside large combustion engines and the need for a highly flexible system that can easily be installed and adjusted to different mechanical tolerances have kept existing solutions from being reliable methods of temperature monitoring on these rotating bearings. By way of an introduction some selected information on engine damages and in particular damages following from a detected crosshead and-or crank pin bearing failure situation have been reviewed. Possible causes for such failures are also discussed. Alternative methods of detecting a bearing failure situation are discussed. Both direct and indirect methods of bearing temperature measurement are considered. It is described how a wireless technology-based solution has been applied to try to develop a reliable real-time temperature monitoring system capable of being permanently installed in a diesel engine.

A pro-active safety management system for ship structures that quantifies the aging effect such as fatigue and corrosion on ship structural integrity is proposed as a new approach to the ships structural surveys that have conventionally been done according to a more passive management system. In a proposed fatigue management system called the Hull Fatigue Management System (HFMS) using Fatigue Damage Sensors (FDSs) it is an important problem to improve the prediction accuracy of hull fatigue life using the FDSs. The characteristics of the FDSs that are in use for fatigue life evaluation by monitoring structural members in ship structures are discussed in order to improve the prediction accuracy of fatigue life exposed to random wave loads such as storms under various loading conditions peculiar to ship structures. Factors affected by random loading against constant-amplitude loading and mean stress levels are introduced for the evaluation procedure using FDSs and confirmed by a series of fatigue testing and numerical simulations. This newly proposed fatigue life evaluation procedure using obtained factors is checked by comparison results of fatigue tests for a large structural model on which FDSs and strain gauges are provided simultaneously and to which random loads by assumption of storm patterns are applied under various mean stress levels. Practical application results of the FDS for an LNG Carrier for 5-year operation are discussed.

Many of the current practices applied for offshore production managing emphasise those aspects related to the efficiency of oil and gas production and exportation. Nowadays due not only to the inherent technical challenges associated to deep-water applications but also to the increasing importance of the HSE aspects and requirements faced by the industry a crescent demand to implement a philosophy which focalises safety reliability and integrity of their subsea flowing systems is taking place. The handling of monitored data in order to help the pipe operator to control fluid transportation throughout flexible pipes is an old practice performed by Petrobras and other oil companies in the world. However the idea of acquiring a product which has been conceived designed and manufactured with both intrinsic monitoring and expert systems is a recent idea. The tendency of the main flexible pipe manufactures is normally to face the problem from the traditional point of view: those systems are considered dissociated one from the other and as appendices to be installed in the field after system connection and start-up. Experience demonstrates that the installation of tho97141 Integrity management system for fixed offshore structures inspection strategy

Shipping is the backbone of the global economy and facilitates transportation of more than 80% of world trade.1 A single bulk cargo ship of 250 000t can carry up to 75 000t of ballast water. It is estimated that one billion tonnes of ballast water is carried around the world each year.2 Translocation of organisms through ships is considered to be one of the important issues threatening the naturally evolved biodiversity and the consequences of such invasions are being realized increasingly in the recent years. The International Maritime Organization (IMO) a specialized agency for the United Nations administers the international regulation of ship safety and the prevention of marine pollution from ships. It has been working through its member states to tackle the problem of ballast water since 1973 and adopted the International Convention for the Control and Management of Ships Ballast Water and Sediments in 2004. The convention includes a ballast water performance standard (based on the quality of ballast water that can be discharged). Research and development initiatives around the world are underway to develop technologies that can meet the standards set by the IMO convention. Among the major mechanical constraints to the ballast water treatment technologies that are being developed is the availability of space on board and the flow rates to be achieved.

Considering the current trend of shipping industry the enhancement of comfort and safety in navigation should be taken into account at the ship design stage. But in the early design stage the ship owner and captain can only obtain very limited information about the performance of ship manoeuvring if at all. This research aims to develop a multi-function ship simulation system by extensive use of ship simulation and VR (virtual reality) technologies its purpose is to provide the opportunity for ship owner and captain to perform 'virtual sailing' and understand the performance of own ship and even hold the ship training at the design stage. The most important achievement of this research is the establishment of a low-cost PC-based ship-simulating system which considers the 6 DOF (degree of freedom) motions in waves and develops a mathematical database for various kinds of vessels. The system may be used to evaluate the manoeuvring and seakeeping performance of a ship in early design stage for the purpose of improving qualities of design work. The service to yacht builder is also an important part of USDDC's work. It is believed that a more intuitive display system like this could provide yacht designers and owners with a communication platform and might work as a good mean for promotion.

The deepwater well 1-SHEL-14-RJS (block BM-C-10 in the Campos Basin offshore Brazil) was successfully drilled by Shell Brazil in May-June 2003 to beyond 5200 m total depth in 2887 m water. This was done using the Stena Tay a DP (dynamically positioned) semi-submersible with a surface BOP system. The SBOP system included a SBOP (surface-mounted BOP) a high-pressure casing riser a SDS (seabed disconnect system) and control systems for these components. In order to use this equipment on the Stena Tay a number of relatively minor rig modifications were completed prior to the start of operations. Throughout the project planning phases an intense and comprehensive risk management process was followed. The results of this work concluded that SBOP operations are as safe if not safer than conventional operations in terms of HSE (Health Safety and Environment). The operation was successfully completed without any significant HSE incidents. During the operations with the SBOP system a large number of learning and ideas for improvements to the system were gathered. These improvements will be prioritised and implemented for future SBOP drilling campaigns. Overall the SBOP operation on BM-C-10 was extremely successful particularly when considering that this was the first application of a new technology in an extreme environment conducted from a dynamically positioned vessel in record breaking water depths for Brazil. This heralds a new era for such operations and provides a strong basiX43230

There has been growing concern over the increasing loss of bulk carriers. Many disappear without trace and with the loss of many lives; fatigue and fracture seem to be a common cause in many cases of serious hull casualties. Current Classification Society policy is to repair any crack that appears in a structure as soon as possible. The risk associated with leaving these defects unrepaired while the ship is in service has yet to be quantified. Work is presented that is underway to provide a tool that would help quantify the risk of leaving a crack-like defect in a ship structure and to calculate how long it would be safely left unrepaired. To accomplish this a deterministic fatigue program is developed based on simplified wave loading in which the long-term distribution of stress cycles is calculated based on two-parameter Weibull distributions rather than summing up the load diagrams for various sea states. The program can calculate the allowable stress range for a given type of joint detail or can calculate the damage ratio for a given maximum stress range on the structural detail. Based on this deterministic model failure surface for the fatigue limit state function is generated and used in a reliability analysis program and a Bulk Carrier structure is analysed. Safety indices are then evaluated at several locations of the longitudinal structures and a sensitive study is carried out. A brief outline of work based on fracture mechanics approach is also given.

As the oil and gas industry is building much larger LNGC than so called standard size and is also considering operation in partially filled condition a more accurate and realistic assessment method and criteria are needed. In the past a simple methodology has been used to define the load and strength of the containment system to evaluate the factor of safety of the system. To meet the new demand of the industry. ABS has developed a procedure for the strength assessment of a membrane type containment system based on the combination of numerical analysis and experimental study. This paper is to present the technical background of the analysis procedure. The method for determining the load and strength of an LNG containment system and the acceptance criteria are to be described. For load sloshing model test requirement and procedure to determine the critical load cases and test conditions using sloshing simulation are to be presented with experimental results. Strength side of the equation dry and wet drop test procedure and how these test results are used in the determination of realistic impact strength including the interaction between the fluid and containment structure and dynamic structure analysis utilizing dynamic material characteristics and structure damping. The analysis procedure to evaluate two main containment systems will be presented with a nexample analysis. Results are summarized in the conclusions and recommendations are made for further study.

Despite all efforts made in increasing safety of ships by optimising their structure to resist heavier seas the impact of an extreme single wave like a Freakwave wave groups like the Three Sisters or wave trains with adverse frequency characteristics will always represent exceptionally dangerous situations. As forces and motions induced by such waves can be enormous these situations should be avoided whenever possible. A method is presented to calculate the wave train a ship will encounter from surface elevation snapshots of the surrounding sea taken by the ship radar. The time-dependent surface elevation snapshot far ahead of the ship is transferred into frequency domain by the use of FFT (Fast Fourier Transformation). The resulting complex Fourier spectrum given over the inverse wavelength 1-L is converted into an amplitude spectrum and a phase spectrum. By shifting the phase spectrum to the position of the cruising ship the encountering waves can in turn be calculated in advance - depending on speed. The permanent processing of incoming snapshots delivers a continuous prediction of the water surface elevation at the position of the cruising ship. Based on these data the expected ship motion behaviour can be calculated continuously in time domain. In addition the response spectra resulting from the wave spectrum and the relevant RAOs are also evaluated. As wave data far ahead of the ship are used it allows a forward glance and dangerous situations particularly resonance and parametric resonance are detectable before the ship is encountering this wave train. Consequently theX31668

The SSS (submersible surface ship) is a ship based on a novel concept in that it she sails on the surface like conventional ship but avoids rough seas by going underwater to a sufficient depth. The wings of the SSS produce downward lift to balance with the residual buoyancy. Therefore the SSS is expected to be able to keep both safety and arrival time even if she encounters unexpected bad weather. In this paper the 6-DOF (six-degree of freedom) motion of an SSS is studied. Equations of motion are formulated and procedures for estimating hydrodynamic derivatives are presented. Hydrodynamic derivatives are estimated for a proposed SSS configuration a ship hull with a pair or main wings and a pair of horizontal tail wings. Calculation of the 6-DOF motion is carried out. Results of the calculations show some specific aspects of the SSS especially for effects of the elevator of horizontal tail wings the aileron of main wings and the rudder. It is confirmed that the existence of static restoring moment for roll and pitch and no vertical tail wing makes the 6-DOF motion of the SSS different from that of airplanes.

A pipeline is the most effective and reliable way of transmitting oil and gas to the consumer. Oil and gas pipelines are high-pressure vessels so safe and reliable operation of the pipeline is particularly important especially for high-pressure gas-transmission pipelines. Failure investigation showed that fatigue fracture is a major contributor to pipeline failure. Fatigue fracture is usually caused by alternate stresses acting on the pipeline which derive from inside pressure fluctuation vehicle running overhead or river scour etc. The service life of pipelines may be estimated on the basis of the number of cycles to cause fatigue crack initiation in defect-free material or fatigue crack propagation from an initial defect. Methods of design and prediction of fatigue life for structure as well as establishment of inspection and assessment period have been given in many specifications but few fatigue test data has been achieved for the modern pipeline steels which bring about many difficulties to the pipeline design and safety assessment. In this paper a full-scale fatigue test is carried out to study not only the fatigue life but also fatigue crack developing behaviour. The sample pipe is grade API X60 and outside diameter 660 mm with an artificial outside defect. There is some relationship between full-scale and lab small-size fatigue crack growth tests. The study verifies and validates reliability of small-size fatigue crack growth tests.

The world's use of natural gas is increasing. For long distances LNG represents the most efficient commercial alternative but economically competitive systems for smaller volumes and shorter distance trades like CNG (compressed natural gas) are emerging. The work carried out by DNV to meet the new challenges facing the gas carrier industry is described. The emphasis is on sloshing loads and tank system strength for normal tank fillings as well as reduced tank filling operations of membrane-type LNG carriers. The current applicability of CFD (computational fluid dynamics) computer codes in sloshing analysis is discussed. Results from scaling model test results between different model scales are shown and it is concluded that a full-scale sloshing measurement campaign is necessary to better understand the model scaling issue. Short-term expected extreme as an estimate for expected lifetime extreme sloshing loads is discussed and some remarks are given on sloshing loads at low filling ballast operation compared to high filling full load operation. Due to the current shortcomings in the CFD analysis tool DNV has concluded that sloshing load determination has to be based on model testing. As uncertainties still exist in the determination of absolute values of sloshing impact loads comparative approach has been selected for the containment assessment procedure in the new DNV guideline on 'Sloshing Analysis of LNG Membrane Tanks'. The status of the emerging CNG shipping industry is outlined. Work is in progress foX33017 Gas carrier safety handbook