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Tropical cyclones (TCs) occur in seven ocean basins: tropical Atlantic northeast Pacific northwest Pacific southwest Indian north Indian southeast Indian and south Pacific. While sea surface temperature plays a role in the genesis of TCs the upper ocean heat content contained between the sea surface and the depth of the 26C isotherm has been shown to play a more important role in TC intensity changes. Sudden TC intensification has been linked with high values of upper ocean heat content contained in mesoscale features particularly warm ocean eddies provided that atmospheric conditions are also favorable. Therefore resolving the upper ocean mesoscale field is critical to monitor the upper ocean heat content. Sustained hydrographic and in situ observations cannot resolve mesoscale features and their vertical thermal structure with a spatial and temporal resolution sufficient for TC intensification studies. This paper reports a summary of some of the current work being carried out to investigate the role that the upper ocean plays in TC intensification. The TC intensity forecast in some of these basins has already incorporated upper ocean thermal information either in research or operational mode. While most of the focus of TC intensification studies has been in the North Atlantic and the North West Pacific basins there are now efforts being carried out in the rest of the basins. Examples are presented here on how ocean data and products are used by the scientific and operational communities to investigate the link between the ocean andX41737 Applications of seismic depth imaging

Increasingly the skills of industrial designers are being recognised as relevant to the design of marine vehicles. Verified techniques for teaching 3D design based on automotive design studio practice have a direct link to the methods applicable to marine designers. The primary intent to migrate the process by using these techniques for aesthetic development tools is reported. This also brings to light additional specific benefits to marine design especially fairing of surfaces such as hull forms. By using a combination of semi-rigid foam automotive clay and computer model visualisation controlled development of complex surfaces and their intersections allow visual auditing of form at an early stage in the design process. Considerable use is made of advanced 'intuitive' tools to enforce continuity across all surface edges when: 'curvature with constant rate of change of the rate of change of the curvature' is required. In turn fairing of hull surfaces optimising changes in surface structure permit inclusion of surface continuity across stepped forms and the rapid manipulation of hull and topside surfaces is also improved. Capturing physical hulls made from automotive hard styling clay or rigid foam using non-contact laser scanning is also described along with a discussion of the procedures of converting 'cloud data' first into polygons and then fitting computer splines onto this data are further explored for boat design. Export of data from any of the routes described to naval architecture software to check stability and performance

The book has been written from the standpoint of a practising designer rather than that of a teacher. An introductory chapter which includes ship terms, symbols and notations and other useful information. The following chapters cover hull form - delineation and geometry including lines drawing, fairing line and sheer line; the calculation of areas, moments, etc, including use of Rules such as Simpson's, Durand's and Tchebycheff's; fluids at rest - first principles, including total and centre of pressure and buoyancy; transverse stability, including metacentre, heeling and righting moments, inclining experiment; trim, longitudinal stability and addition of weights; hydrostatic curves and the displacement sheet, including centres of buoyancy and wetted surface; rules for freeboard, subdivision and stability; fluids in motion - first principles, including Bernoulli, Venturi and Magnus; fluids in motion - gravity and viscosity effects, including Reynolds and Froude; the properties of waves; surface friction, including Froude's, Reynolds' and Gebers' Experiments, boundary layer, frictional calculations; residual resistance and form; experimental testing tanks or 'model basins'; air resistance and sail propulsion; marine propellers, including jet propulsion, paddle wheels, propellers and propeller design; the powering of vessels; the design and powering of planing craft, including planing hulls, stepless and stepped hulls; motion in a seaway; the strength of ships; the vibration of ships; launching calculations; materials of construction, including wood, steel, alluminium alloys and issues of corrosion; some design problems, including sections on tonnage regulations, weight estimates, special types.

High pre-tensioned mooring lines as present in deepwater offloading terminals suffer fatigue damage from local bending effects. Recently the phenomenon of OPB (out-of-plane bending) fatigue of mooring chain links emerged as an important parameter in the fatigue assessment of mooring lines. Vessel motions induce a bending moment at the top chain of a mooring line. This bending moment induces alternating local stresses in the link and thus contributes to fatigue damage of those links. High pretension mooring systems are particularly sensitive to this phenomenon since a small vessel motion combined with a high tension results in a relatively large bending moment in the upper mooring chain links. In mooring systems with high pre-tensions this damage is of much greater magnitude than the fatigue damage induced by tension-tension loading only. An extensive study has been executed to investigate the fatigue life of mooring chain in deep water systems. This paper presents the calculation procedure to include the effects of local chain bending in the overall mooring line fatigue analysis. It was concluded that despite the complexity of the OPB issue it is a phenomenon that can be incorporated in the mooring analyses by means of numerical procedures. The developed method is based on extensive FEM (Finite Element Method) analyses of chain links. Models of multiple chain links have been used that take into account the plastic-elastic properties of the material and contact friction between chain links. The FE models are used to derive empirical relations between load angles inter-link angles bending momentX40559 Calculation model for the reliability characteristics determination of marine power plant with serial functional connections

The Canyon Express development is a three operator subsea development consisting of the transport of gas-condensate from deepwater subsea reservoirs to a host platform via dual 47-mile 12-inch nominal OD flowlines. The operation of the development is described. It involves ultra-deepwater reservoirs from three individual operators flowing into a common subsea multi-phase gathering system. It is explained how to optimise the operation of Canyon Express over the life of the development the respective reservoir models from each operator were integrated with the thermal-hydraulic steady-state model for the dual flowlines while considering reservoir decline production liquids methanol injection topside facility constraints and decreasing host platform arrival pressure. The simulation of the normal operation of this development is performed using a steady-state reservoir and flowline simulation with Baker-Jardine's FPT (field planning tool) and PipeSim-Net. The focus of this work is to help determine the strategy to maximise recoverables and to determine each operator's volume allocation and excess capacity over time. Maximisation of recoverables by reducing pressure at the host platform is considered. The commercial operating philosophy is explored. Design data and assumptions are identified followed by model development and calculation process. Next the calculation process is detailed. Finally results are presented. Graphs and diagrams appear on pages 7 to 11.

Advanced CFD (computational fluid dynamics) simulations of engine reacting flow processes have emerged as a complementary and efficient design tool for the development of next-generation engines. Many of the early multi-dimensional CFD attempts to predict engine combustion rates were carried out using simplified chemistry. In the present study hydrogen-diesel dual fuel combustion CFD analysis is carried out using FLUENT software to study the effect of hydrogen substitution on turbulent kinetic energy TDR (turbulent dissipation rate) combustion flame velocity and NOx formation for five compression ratios. For Turbulence analysis RNG k-e model is used which is further modified for the dual fuel analysis. Meshing of the combustion chamber is carried out using GAMBIT by tetrahedral element using cooper tool. To analyse the effect of compression ratio in dual fuel mode compression ratios were varied along with hydrogen substitutions. To validate CFD results experimental investigations were carried out which showed a good agreement between the predicted and experimental results.

In recent years many new concepts of floating platforms which are applied to oil and gas exploitation in deep water have been developed including FPSO (floating production storage and offloading system) TLP (tension leg platform) semi-floating production facility and SPAR platform etc. These platforms are usually located in severe ocean environments. Due to the large investments and high risks their hydrodynamic performances such as motions environmental forces and structural responses in survival conditions need to be investigated and reliable model tests need to be carried out based on correct modelling of wind waves and current in deepwater offshore basin. The current generation system in deepwater offshore basin is important for the correct modelling of the ocean environment. It is generally considered to be a challenge to obtain uniform and stable current flow in the basin. As technical assurance numerical and experimental studies are carried out to investigate the characteristics of the deepwater current generation in the basin RANS (Reynolds-averaged Navier-Stokes) equations and the standard k-e turbulence model are adopted to simulate the current generation system numerically. In addition a 1:10 scaled model test is also carried out. In both numerical and experimental studies horizontal and vertical current velocity profiles turbulence levels and pressure losses during the current recirculation etc. are studied. It is concluded that the perforated walls are key components of the current generation system. In addition various vertical current velocity profiles can be realised in the basin.

Long-term exposure to DPM (diesel particulate matter) emissions are linked to adverse human health effects due to the potential association of DPM with carcinogenicity. Current diesel particulate matter emission regulations are based solely upon total mass concentration although it is the sub micrometer particles that are highly respirable and most detrimental to human health. In this study a multi-nozzle electrospray system was developed as a charged droplet source for cleaning a gas contaminated with fine particulate matter. Experiments were carried out with an EWSS (electrostatic water spraying scrubber) to evaluate its performance for DPM concentration removal based exhaust gas emissions. A diesel engine using marine diesel oil operating under varying load conditions was used as a stationary DPM emission source. The EWSS was evaluated under various operational control parameters such as applied voltage gas residence time water conductivity size of droplets to determine their effect on overall collection efficiency as well as particle size dependent collection efficiency. In addition it was found that collection efficiency was directly related to the applied voltage with increasing collection efficiency measured for increases in applied voltage. The EWSS collected ultra fine DPM from marine diesel engine with high efficiency and total collection efficiency is over 90 per cent of all particle sizes an88828

Canada's Oceans Act (OA) was passed in 1997 to deal with the management of coastal and marine environments. Part 2 of the Act contains provisions for the Minister of the DFO (Department of Fisheries and Oceans) to lead the development of a national strategy for oceans management based upon the principles of sustainable development integrated coastal and ocean management and the precautionary approach. The OA identifies the establishment of MPAs (marine protected areas) as an important initiative for conserving and protecting marine resources. Since then the DFO has been working toward developing the MPA Program. A main focus of this programme is the conservation and protection of habitats for both commercial and non-commercial fish species. In the Newfoundland Region the Oceans Programmes Division of DFO has been seeking partnership arrangements with interested stakeholders to identify potential MPAs. The DFO has responded to numerous requests from community groups concerning MPAs in coastal areas. Through a regional process DFO has announced two sites as potential MPAs: Gilbert Bay and the waters surrounding the Eastport Peninsula. The next steps in the process are to establish local steering committees to consult the proposed MPA initiative and to develop a management plan. The DFO in the Newfoundland Region is committed to continuing work with community groups on developing MPA proposals and exploring opportunities for new partnerships with interested stakeholders.

This paper deals with the coupling between biomarker responses and modelling environmental risks for environmental impacts in the field. The ERMS (environmental risk management system) project aims to develop models for prediction of impacts from regular releases to sea caused by offshore industry. The types of discharges considered are discharges during production (basically produced water releases) and discharges during drilling (basically discharges of drill cuttings and mud). The main purpose of the ERMS project is to develop risk-based tools for predicting potential environmental impacts caused by the regular releases to sea generated by the offshore industry. In order to validate risk estimates calculated with the ERMS model a field trial was carried out using cages with sea scallops and blue mussels in the vicinity of an offshore drilling platform. The biomarker data were then compared with risk estimates obtained with the numerical model developed and the relationship between them was determined. A project called 'Validation' over the NFR PROOF Programme combined forces with the ERMS project. This validation project aimed to validate methods for carrying risk analysis offshore. The methods validated could then be tested on the real field case by comparing risks deduced from the responses of the biota with the risks calculated by the numerical models developed as part of the ERMS project. Results presented here are an extract from a part project report from these two projects (presently under development)100688 Comparing commercial and research survey catch per unit of effort: megrim in the Celtic Sea Pierre Petitgas ; Jean Charles Poulard ; Alain Biseau

BWE (ballast water exchange) has been and remains the primary management practice with widespread application for reducing the spread of non-indigenous aquatic species via ballast water. A study is presented which uses experimental and CFD (computational fluid dynamics) methods to examine the flow behavior inside ballast tanks during flow-through BWE (ballast water exchange) and which investigates the exchange effectiveness. Validation efforts are carried out based on comparisons with data collected in a one third-scale model of a portion of a typical ballast tank for a bulk carrier. Comparisons between the measured data and computational predictions are in good agreement. Numerical simulations are also carried out for a typical full-scale ballast tank in a 35000 dwt handysize bulk carrier a ship type that represents a large proportion of the oceangoing vessels that ply the Great Lakes trade routes. The results of this study may help explain the variable results of ballast water exchange experiments documented to date lead to ballast tank structural modification recommendations to improve overall ballast water exchange effectiveness minimise deadspots reduce sediment deposition and accumulation and provide the insight and knowledge to select and enhance treatment technologies thus reducing the threat of coastal invasive species being discharged in coastal ecosystems.

Corrosion is a major issue for the structural condition of a vessel during its service life. For tankers and bulk carriers this is even more crucial due to the exposure of the structure to salt water and also to other abrasive substances in the cargo spaces. The focus here is monitoring corrosion. In order to monitor the condition of structural components condition assessments are carried out within the scope of class surveys statutory surveys and ship owner's surveys at regular time intervals. Currently there is no standard for the storage of thickness measurement data. A new computer tool has been developed and is presented to support the thickness measurement process from planning through recording to visualisation. The PEGASUS system makes use of a neutral data format for hull condition monitoring data which has been developed for this purpose in the CAS project. The main purpose of this data format is the easy association of survey findings with their location on the ship. Ship owners will be able to view results of thickness measurements in 2D and 3D visualisations with a special viewing program. Instead of preparing sketches and drawings after taking the measurements a structural model of the ship will be prepared before an inspection. A derived HCM model can then be used to plan the measurements which means the inspection results can be presented earlier to the ship owner and potential sources of error should be reduced.

The University of New Hampshire has been involved with an Open Ocean Aquaculture demonstration project for the last 10 years in the western Gulf of Maine. As part of an environmental monitoring program a mooring has been deployed at the field site 10 km off the New Hampshire coast about 9 months each year. Since 2005 dissolved oxygen sensors have been deployed on the mooring. Oxygen was measured by Sea-Bird SBE-43 sensors powered and recorded by SBE-16 Plus SEACAT's located about 22 m depth and about 2 m above the bottom. The sensors were calibrated and checked yearly by Sea-Bird. In situ calibration of the moored oxygen sensors was also done with water samples and Winkler titrations about 6 times a year from 2005 and 2008. The difference between the moored and water sample oxygen concentrations showed a nearly linear drift with time. The drift rates during each of the years and for each sensor (at different depths) were not the same. As the SBE-43 sensors have no apparent zero drift the drift was corrected by a time changing sensitivity which was applied to the data. The resulting time-series showed the dissolved oxygen variations with time over a year and showed low values of dissolved oxygen in the deeper waters in late summer and fall. With the successful correction for the sensor drift the climatology of the Western Gulf of Maine can be studied in more detail and related to the spring and fall plankton blooms the biological cycles and health of the Gulf.

Bunker fuels cannot yet be traded in e-commerce. This will only be possible if the quality of the fuel can be quantified. Heavy fuels do not have a cetane number to give an indication of ignition quality. However various ignition and combustion properties may be determined using the FIA-100 (fuel ignition analyser). An ECN (equivalent cetane number) is obtained based on the time delay between the start of ignition and the rise of chamber pressure to 3.0 bars. This time delay is referred to as SMC (start of main combustion). More than 50% of global fuels have ECN values less than 19. Since the instrument fails to give such low values it is proposed that SMC may be used instead of ECN as it is obtained for the entire range of fuels. 214 samples collected worldwide were tested. A very good correlation of 0.88 is observed between SMC and True Worth Index an overall fuel worth indicator presented to the bunker world community since 2001 from Viswa Lab. The true worth of a fuel can be obtained using a single parameter SMC derived from FIA-100. This would help in paying the right price for the right fuel in the bunker market.

The development of oil and gas reserves in deeper and deeper water faces a significant challenge to reduce costs in a selected development scheme. Typically today at least the largest proportion of any development cost is associated with the time and effort required to drill complete and workover the wells that are then to be produced. Drilling vessels at the present time are operating at very high day rates (spread costs for some operators are in the order of $1million per day). Thus the attractiveness of dry tree floating production facilities such as spars or TLPs has significantly increased within the water depth limits of these facilities. These facilities provide direct access to the wells below the production platform. Key aspects in the selection and design of a dry tree unit are the feasibility of the associated risers and the impact they have on the vessel specification. Since by their very nature TTRs are supported at the surface tension requirements and the ability of any tensioning system and-or vessel to support the risers is a critical aspect of any TTR design. Dual and single casing top tensioned risers are widely used by operators for deepwater floating production facility developments. These riser types provide direct vertical access for completions and workover. These single and dual barrier risers are a stable riser concept using the effective tension distribution between casings and tubing to mitigate any collapse or buckling concerns. However the interaction and load paths of these riser strings are quite complex and require careful planning and analysis to ensure safe installation and Critical assessment of global and regional disaster vulnerabilities strategies for mitigating impacts George Pararas-Carayannis

The ALARP (as low as reasonably possible) principle is examined with respect to riser selection and integrity management. As part of the South Everest subsea development the additional of a new hydrocarbon riser to the CATS (Central Area Transmission System) riser platform is being considered. This is a potential source of additional risk to offshore personnel and to the integrity of a key offshore asset. Great scrutiny is placed on the steps taken to ensure that these risks are kept to a level which is ALARP. The key points of the work programme looking at detailed development of two alternative design options are highlighted. These include a FMEA study a constructability review a quantified risk assessment key sensitivity studies and CBA (cost benefit analysis) specific design features demonstrating ALARP a programme of integrity testing and planning for ongoing integrity management. It is concluded that as health safety and environmental management systems become more integrated into business plans there is likely to be increasing integration of risk criteria in CBA (cost benefit analysis). However it is pointed out that the key design reviews (such as the FMEA study described) provide a significant aspect of ALARP demonstration without recourse to CBA.

A new autonomous platform has been developed that can provide the benefits of an untethered drifter while also providing the benefits of a stationary buoy. The BSOP (bottom-stationing ocean profiler) is an instrument platform that stations itself on the sea floor and ascends and descends autonomously to gather water column profile data. While at the surface the BSOP transmits acquired data via the ORBCOMM satellite system to provide researchers with a near real-time observation of the study area. The BSOP unit is designed to remain at sea for extended periods up to several months. It uses an oil-based buoyancy control system to ascend and descend at speeds of up to 0.5 meters per second. The unit is low cost easy to deploy and recover using only light-duty gear and can support a wide variety of sensors. Command scripts are downloadable while the unit is in communication with a satellite ground station; this permits reprogramming of mission parameters if needed. The unit has an integral GPS (global positioning system) receiver to accurately identify surface position. This is important to the scientific mission but is also used for recovery operations. BSOP design and early results are presented.

Deep ocean minerals like manganese nodules cobalt rich manganese crusts metaliferous mud and sulphide deposits are viewed as potential resources to satisfy the increasing demand of metals in this century. Among these minerals extensive exploratory surveys and a few deep-sea mining tests have been done only for manganese nodules. Deep ocean mining of manganese nodules presents one of the major challenges in technology in areas pertaining to complex design of machinery for long duration operations at about 5000 m depth on soft ocean floor. Design synthesis for such systems has to be done keeping in view device interactions cascading effects of probable failures in hyperbaric subsea conditions apart from main functional requirements. In the present study conventional design synthesis approaches have been enhanced with design fusion methodologies developed like structured mutual fusion function sharing approaches for reinforcement buoyancy and protection mutual balancing of dynamic forces and reactions of devices. Bionic design methods with analogies to nature can be used effectively in design fusion for manganese nodule collection systems. Case studies of failure and its cascading effects experienced in deep seas have been studied and factors to be taken care in design synthesis mentioned. The paper describes in detail the methodologies developed and design synthesis approaches that can be used for designing deep ocean manganese nodule collector systems.

UUVs (unmanned underwater vehicles) used for mine hunting and surveillance are required to operate over a large range of Reynolds numbers. When moving to a region of interest or surveying a region they may be required to move quickly. Conversely detailed investigation of an object requires low speed manoeuverability. These UUVs operate for at least part of the time at RN (Reynolds numbers) where laminar boundary layers may occupy a significant portion of the body surface. Attempting to model the fluid flow around these vehicles using standard implementation of a RANS (Reynolds Averaged Navier-Stokes) turbulence model is likely to result in inaccurate prediction of body forces and flow structures if the transition of the flow is ignored. The equipment and methodology used to measure the state of the boundary layer on a 3-1 prolate spheroid is described. This equipment and methodology were used so that boundary layer behaviour could be examined within the AMC (Australian Maritime College) Cavitation Tunnel. This work was carried out as part of a larger project to understand the flow about UUVs (unmanned underwater vehicles). A summary of some results for flow about a prolate spheroid is provided and discussed.

Seam welding is a fusion welding method that uses Joule heating as the heat source. The work to be welded is squeezed by the electrode force. The pulsed welding current is applied through the electrodes during their rotation. The Joule heating melts the work and the cooling effect of the electrodes controls the size of the nugget. If the welding conditions are selected appropriately a sound continuous nugget can be formed. Since high welding speed is achieved once the welding conditions are correctly set seam welding is widely used for welding not only mild steel but also aluminum alloys and stainless steels. The quality of the weld is strongly dependent on the selection of welding conditions. In the case of an LNG carrier the number of plates to be joined and the combination of their thickness have wide variations. It may be necessary to spend considerable time and effort to carry out experiments for the selection of the optimum welding conditions for all possible cases. One of the solutions is the effective use of computer simulation such as FEM. Therefore a finite element method is developed in this study and its versatility is examined.