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Market-orientated designing of modern high-performance diesel engines is very complicated starting with the initiation of an optimization process. Problems for the designer to solve are described and suggestions are presented for ways to design an engine series based on the engineering sciences. The example selected for study is the design of a high-speed high-performance diesel for use in fast vessels for which the power-to-weight ratio is especially important. Beginning with a market analysis it is demonstrated how initial optimization of the major parameters for the main application and positioning within the power spectrum of the existing engine occurs.

The Eastern Trough Area Project (ETAP) consists of the BP operated Marnock Mungo Monan and Machar (the M fields) and the Shell/Esso Heron Egret and Skua (Heron cluster) developments. BP and Shell will run ETAP as two separate fields during the development phase but once in production BP will assume operatorship. The ETAP development involves the construction of a two platform Central Processing Facility (CPF) located over the Marnock field which will provide processing facilities utilities and accommodations. The CPF consists of a Processing drilling and Riser (PdR) platform bridge-linked to a Quarters and Utilities (QU) platform over Marnock and a not-normally manned platform on Mungo. Two major alliances have been formed with ETAP; the ETAP Facilities Alliance is believed to be the largest alliance type relationship undertaken to date in the North Sea.

This paper begins by giving a brief review of the basic phenomena of ele ctrostatics and the electrostatic hazards presented by tank washing and the pumping of refined products. Precautions to safeguard these operations are also detailed. Recent investigations by Shell Research Ltd into potential hazards of inert gas and GRP pipes on crude oil and products carriers are described. Electrostatic properties of inert gas supplied to cargo tanks have been established and the space potential obtained during inerting was measured in the tanks of a VLCC and VLOO. The decay behaviour of the potential is reported. Also described is the development of a GRP pipe made adequately conductive by the addition of small quantities of a filler to the resin.

This report describes work which forms part of an agreed programme of research conducted on behalf of Marine Division, Department of trade. The separation of Marine Traffic flows in the English Inshore Zone and the Westbound Lane of the Dover Strait has been examined before and after the laying of two buoys to mark the separation line. No clear changes in the flow distribution have been detected, although there in some indication that the proportion of traffic passing within ¼ nautical mile of the CS1 buoy position i.e within the separation zone off Dungeness has reduced slightly over the complete period during which recordings were made.

Advanced wastewater treatment technologies wastewater reduction and water recycling initiatives are considered the most practical water conservation strategies available at present. Reuse is becoming the popular alternative in responsible wastewater treatment and water resource management. A comprehensive pilot study was carried out to evaluate a small footprint high efficiency MBR (biological membrane) wastewater treatment process to produce reuse quality water to address water shortages and continued development in a US federally designated sole source aquifer area. The treatment process included a high-rate primary settling unit with coagulant enhanced settling and phosphorous removal followed by four-stage BNR membrane filtration. The goals of the study are described. The study included testing process control strategies and assessing the addition of coagulation to enhancing settling and nutrient removal. Tests on the system were carried out to determine operational variables and requirements during high flow rates ammonia challenges cold and wet weather conditions low BOD and nutrient loads and biological upsets.

The application of simulation in the maritime environment is described. The expert system can apply human reasoning to evaluate the state of a system and can act on triggers and providing a powerful environment for virtual prototyping of logistic systems. A simulation model-based investigation for the Port of Richards Bay is discussed. This model was commissioned by NPA to predict storage and berth requirements given the expected increase in commodity throughputs. The methodology of building a simulation model is described together with some practical guidelines for applying a simulation model to a real-life problem.

An attempt is made to look back and briefly track the main events which have led to the current position with port waste reception facilities. Firstly a look is taken at IMO 1973. Next the basic hypothesis behind the provision of waste reception facilities at the ports is outlined. The effectiveness of MARPOL is addressed followed by new pressures in the 1990s and some facts. It is pointed out that while the problem is on the ship the alternative of simply instructing ports to implement port waste management plans seems much easier. After this the voluntary system sticking points for the ports the statutory phase elsewhere in the UK and the situation in Brussels are each considered in turn. Lastly environmental priorities are outlined.

A model of oil behaviour in ice-packed waters is presented. The model was built on the basis of an ice-formation model and a hydrodynamic model in response to increasing oil pollution danger in Antarctica. Oil drift spreading and diffusion in the presence of ice are considered. Results show that the presence of ice modifies the classical spreading of an oil slick by shrinking its area and by trapping some oil in the ice structures. This trapped oil may induce a second spill later. The remainder of the oil is ejected eastwards by the ice pack current. Several case studies are given which back up the results. Further possible applications are discussed.

Pipelines are subjected to different combinations of loadings such as internal and external pressure bending and shear forces. The research programme that led to Dutch guidelines for limit state design of buried pipelines is summarised together with later programmes that focused on offshore pipelines. Limit state design differs from conventional design methods because it specifically addresses each failure mode eg burst collapse etc. The rules of the Dutch pipeline code NEN 3650 are considered and recent developments in international standards are discussed. Practical applications of the pipeline module available in the finite element program DIANA are given and its advantages particularly for evaluating fitness for purpose are highlighted.

The main aim of this study is to experimentally investigate the characteristics of TLDs under wave excitation. An obvious engineering motivation for this study is to explore the applicability of TLD for mitigating the structural vibration of offshore platforms. The structural model used to perform experiments is scaled according to a full size platform by matching its dynamic properties. Circular and rectangular TLDs with different sizes and water depths are examined. The experiments are conducted in a 2-D wave flume. The effectiveness of TLDs is evaluated based on their response reduction. By observing the performance and the behavior of TLDs through laboratory experiments the study investigates the influence of a number of parameters including: container shape container size number of damper incident wave characteristics frequency ratio and mass ratio.

Foam cement use in petroleum well zonal isolation has advantages under certain conditions. Laboratory blenders are used in the design of foam cements which differs significantly from foam generators used in the field. Energy supplied during mixing can affect cement behavior and structural properties. Experiments were performed to characterize the laboratory blender and impeller combination yielding a characteristic blender power function. Test samples included foam cements with varying quality density and cement slurry properties. With blender characterization complete energy input during laboratory mixing was computed using this power function plus blender speed mixing time and slurry rheology data. Mixing energy was also computed on a unit mass basis for selected test samples.

The ERIKA and PRESTIGE shipwrecks demonstrated the efficiency limits of oil spill booms. A physical modelling is presented to reinforce the boom efficiency. Firstly numerical and experimental tests in a vertical 2D section are described. The tests are made on a reduced scale model in fresh water with plant oils. Secondly a simplified structural model for the boom is presented. The equilibrium of a chain with articulated bodies gives the equilibrium equations in 3D. This provides the equilibrium shape of the boom and the possible flight of the boom in terms of stream velocity. Finally an optimisation procedure of the boom plan is described. This takes into account the barrage handling the oil containment efficiency and the barrage storage.

Macroscopic porosity in underwater wet welds is one of the main defects that deteriorate the mechanical properties of the wet welded joints. It is well established that weld metal porosity is a function of pressure thus water depth. However the mechanism of porosity formation is not well understood. Therefore the problem is not yet mitigated to acceptable levels particularly at water depths close to and beyond 100 m. In order to purposely produce porous welds similar to those obtained in wet welding bead-on-plate (BOP) welds were deposited in air with gas metal arc welding (GMAW) with no shielding gas with autogenous gas tungsten arc welding (GTAW) and GTAW with cold wire feed using insufficient shielding gas (8 CFH). After some introductory information a look is taken at the experimental procedures. This is followed by results and discussion.

Significant volumes of heavy and high viscosity oil have been discovered in Campos and Santos Basins offshore Brazil and its commercial production is a challenge for the oil industry. These new areas present heavy oil in the 13-17 API range with oil viscosity between 20 and 400 cP at reservoir conditions. Some of the heavy oil areas are located in shallow waters but most of them are in deepwater which brings extra complexity. Besides the new exploratory areas the heavy oil areas of Marlim Sul and Roncador as well as the Jubarte field with oil in the 16-19 API range will benefit from the development of new production technologies. The focus here is on the development of production units to deal with heavy oil and mainly with large quantities of produced water which could be re-injected in the reservoir. The availability of a rig in the production unit to improve the heavy oil reservoir management process is also being analysed. Operability and maintainability of this type of unit are evaluated

A numerical method is presented for studying viscous flow around a ship hull and also numerical simulations and obtained results to establish the effects of dimensional and movement parameters of the ship on the pressure distributions in surrounding sea water. In this numerical scheme the 3D viscous flow around an advancing ship is computed by the finite-difference method the viscous flow is simulated for ships of a displacement type and the free surface effects are neglected. The governing equations are the Navier-Stokes equations and the continuity equation for the 3D incompressible fluid. The body-fitted curvilinear co-ordinates system is introduced to cope with the body boundary of an arbitrary form. Assuming symmetricity of a flow field only the half side of the center plane is solved. The computational region in the physical space is transformed into the parallelepiped in the computational space. The body boundary is usually transformed onto a plane in the computational space which enables the simple treatment of boundary conditions. Viscous flows around a variant hull of the Wigley model are computed by the present scheme.

During the last 20 years there has been no noticeable change in mine warfare operations; while there has been a real improvement in sonar detection and classification processing concepts of operation have remained the same. The introduction of AUV and USV into the French Navy might be an opportunity to break with the traditional way of conducting minewarfare. The main objective of EXPLORA is to assess the capability of advanced technologies on the littoral reconnaissance concept of operations: MCM (mine countermeasures) REA (rapid environment assessment) and Harbour Protection. At that stage it was necessary for the Navy to find out what they could do with AUVs for R&T defence centres to assess the various technologies and for industry to demonstrate the potentiality of their products. Explora'05 is a concept demonstration that gathers all these needs in a very short space of time and in a single place.

The 3C-Tendons partners' work on the development of a TLP using carbon fibre tendons in ultra deep water is presented. This corresponds to the design of TLPs for different water depths and a given topside load for two solutions using steel or carbon fibre tendons. These results have then been used to make economic comparisons between the concepts. The different structures that have been considered are described with the associated material quantities as well as the actual behaviour. The technical opportunities opened up by the use of carbon fibre tethers are discussed in particular in terms of natural period for the TLP and of overall geometry. A description of the carbon fibre tendon system is outlined. The cost comparison between the different structures is discussed and a range of applications for the different cases is proposed. It is thus shown that TLP can be safely and economically used in ultra deep waters down to the 3000 m range. Conclusions are drawn.

With the economics of deepwater production driving subsea technology development the ability to extend tieback distances is critical to the continued effort to reduce CAPEX for deepwater projects. Programs in subsea separation multiphase pumping and subsea electrical power transmission show the need for high-power high-bandwidth error-free communication where subsea processing and long step-out distances are necessary. These programs have identified wet-mateable high-voltage power connectors and fibre-optic communication and consequently wet-mateable fibre-optic connectors as critical technologies enabling the installation and hook up of the core modules for each project. These technologies are discussed. Photographs diagrams and data tables appear on pages 8 and 9.

This paper details the challenges faced in the design of the Typhoon 18 inch gas export steel catenary riser. The combination of large diameter with the relatively shallow water depth resulted in significant fatigue damage at the touch down point. In Section I the initial design steps for the Typhoon riser are presented. Section II focuses on a refined touch down point analysis including soil-structure interaction effects. Section III presents a new and unique aspect to this project - the measurement and calculation of increased drag coefficients for use in the straked region of the riser operating in the smallest and most damaging fatigue sea-states.

This work aims to develop a suitable methodology for the fatigue assessment of fillet welds subjected to simple or complex normal and-or shear stresses in relevant FPSO details from the view point of weld throat failure. The status of current design recommendations concerning the fatigue capacity of fillet welds was presented by Maddox (2002) based on a literature survey. In order to examine the validity of the recommendations and to supplement the fatigue test database a test matrix with 33 specimens was developed. This included 8 simple fillet welded cruciform joints that were subjected to axial loading and 25 fillet welded tubular specimens that were subjected to axial load and-or torsion for simulation of a combined stress condition in the fillet weld. The data obtained from these fatigue tests are presented. The test data are also compared with design guidance from IIW (1996) Eurocode 3 (1993) and DNV-RP-C203 (2005).