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In April 1997 in-situ operations using Nitrogen Generation Units (NGU’s) were initiated in wells located in the Campos Basin off the coast of Brazil. Nitrogen is used in the petroleum industry in a number of applications. Among these applications are assisted lift (N2 lift and jet lift) using nitrogen foam in certain operations making atomized acid drilling with liquid nitrogen purging tanks and pipelines and making them chemically inert and injecting nitrogen into treating fluids. This work describes a unit that generates nitrogen on-site so that handling liquid nitrogen is eliminated. Some of the recent experiences of its applications in the Campos Basin offshore Brazil are discussed.

This book relates the story of the development of the Andrew oil field in the North Sea, during a time when drastic reductions in development costs had become imperative if the region was to continue to attract oil company investment in an increasingly competitive global market. The book covers the story from the formation of a pioneering alliance in 1993 between BP and seven contracting companies to develop its offshore production facilities, to the production of the first oil in June 1996. Focused on a common business result, the alliance resolved to step away from the constraints of 'business as usual' in its quest to transform Andrew into a valued producing asset.

In order to capitalize on the rapidly evolving autonomous underwater vehicle (AUV) technology base the National Oceanic and Atmospheric Agency (NOAA) chartered a cross-agency working group to coordinate AUV activities in the agency. This team compiled results from pilot programs and analyzed operational results to understand the value of AUVs in NOAA missions. A report entitled "Applying AUVs to NOAA Goals: Current Status and Future Opportunities" was submitted to NOAA senior leadership in 2006. This paper provides an overview of the NOAA AUV opportunities report. It discusses the role of AUVs in major NOAA strategic goal areas such as ecosystem research and management commerce and transportation and climate. Significant pilot programs discussed include coast survey fisheries science and ecosystem research applications. Technical and operational challenges are discussed and recommended steps for further integration of AUVs in NOAA are described.

Great demands on the integrity of the highly-stressed turbine components are made by the growing unit sizes of fossil-fired power stations enhanced steam parameters and the necessity of operating the plant at peak loads. Therefore the detection and evaluation of possible specific natural defects in the rotors and cast-steel components are extremely important in ensuring plant safety and availability. An evaluation of ultrasonic indications is provided covering fracture mechanics analysis and flaw sizing by ultrasonic inspection of rotors. Results of joint research programmes are given. Computer-assisted mechanized in-service inspection of turbine rotors is discussed and the results of in-service inspections of turbine rotors are provided.

Wake-induced riser oscillation can lead to riser clashing. Furthermore the onset of the wake-induced riser oscillation which is typified by its large amplitude and low frequency is attributed to the loss of stability of the downstream riser in the wake once the current exceeds a critical value. The loss of stability is mathematically characterised by a stationary bifurcation. Based upon the authors' previous work further results are presented in the paper on the non-dimensional parameters which govern the critical current speed. These non-dimensional parameters once computed can then be used by riser designers to assess potential riser clashing and/or ascertain the minimum riser spacing and top tension required in order to avoid riser clashing.

The corrosion wastage of deck plates of ballast and cargo tanks is analyzed based on a non-linear corrosion model. This model is able to describe an initial period without corrosion due to the presence of a corrosion protection system a transition period with a nonlinear increase of wastage up to a steady state of long-term corrosion wastage. This model is applied to corrosion wastage data of deck plates collected by the American Bureau of Shipping. The objective of this work is to fit this corrosion wastage model to the service measured data determining the values of the model parameters that represent the best fit to the data so as to describe how corrosion wastage varies in time as a result of generalized corrosion.

Dimensionless forms of Navier-Stokes equations are derived in matrix form directly from conservation laws for one-dimensional transient compressible flow using primitive variables p u p. P-version space-time least squares finite element formulation (STLSFEF) of the GDE is constructed in original parabolic form (i.e. no auxiliary variables or weak forms) in Eulerian frame of reference using C11 type p-version hierarchical interpolations. Time-marching procedure is used to compute time evolutions for subsequent space-time strips. It is demonstrated that numerical solution of Navier-Stokes equations for high-speed gasdynamics for isentropic and non-isentropic shocks is possible to compute without assumptions or approximations. The role and influence of artificial viscosity and thermal conductivity on shock structure is demonstrated. Riemann shock tubes are used as model problems. True time evolutions are reported until steady shock conditions are achieved.

A better understanding of ship stability is necessary to prevent losses of ships due to unstable motions particularly in high seas. The stability of ship motions is analysed using a hydrodynamic model accounting for all the rigid body motions of a ship as well as memory effects in the fluid. A comparison with model tests shows that the computer model provides reasonable results. The influence of the steady wave pattern is assessed for a container ship. Simulations show that ships' dynamics depend strongly on the nonlinearities of the ship fluid system. When wave heights increase a bifurcation before the ship capsizes is noticed. A path following method is used to determine in a systematic manner the stability limits. The application for a simplified system shows the importance of the nonlinearities of the mathematical model.

This work presents the development and implementation of a semi-implicit time integration strategy for the solution of non-linear dynamic problems in the time domain and its application in the analysis of compliant offshore structures submitted to time-varying environmental loadings. The strategy presented here consists in implementing a "hybrid" scheme that combines the advantages of implicit and explicit integration methods: while the former methods allow the use of larger time-step values the latter present smaller CPU cost per time-step. The resulting scheme is a "semi-implicit" method based on an iterative technique to solve the effective systems of algebraic equations that derive from the numerical treatment of the differential equations of dynamic equilibrium. The application considered in this work is the analysis of a guyed tower for offshore oil production. The results and performance of the traditional implicit scheme and the proposed semi-implicit strategy are compared showing that the potential of reduction of computing costs is encouraging.

the advances in pod thruster technology have enabled new hybrid propulsion concepts that combine a single centreline propeller shaft with azimuthing propulsors. These concepts can either have a single contra rotating pod propeller directly behind the main propeller or twin thrusters/pods on either side of the main propeller in the centre line skeg. These new options have in common that they go away from the conventional twin shaft lines used in ferried today and thereby reduce the resistnace of the vessel. The new propulsion options offers significantly lower power demand which also means lower fuel consumption. The new propulsion concepts can be used with either a Combined Diesel-Electric and Diesel-mechanical machinery or with a new advanced diesel-mechanical drive of twin shaft lines. The new concepts also offer possibilities to increase cargo capacity and thereby the earning potential of the vessel.

Over the last few years numerous studies have focused on improving the present understanding of the structure of diesel sprays and identifying the parameters affecting it. It is now well recognised that the fuel injection system of DI (diesel injection) diesel engine as well as the chamber pressure/temperature conditions play the dominant role in the spray development combustion and pollutant formation mechanisms. A comprehensive set of experimental and computational results covering a wide range of the flow phenomena taking place inside a common-rail-based diesel fuel injection system equipped with a VCO nozzle and including their spray characteristics is presented. The test cases investigated include different injection pressures and back gas pressure or temperature conditions of relevance to HSDI diesel engines. A brief description is presented of the various experiments carried out as part of the overall research programme. Then the computational and experimental results are presented and discussed highlighting the most important findings and areas of future research.

A joint report by the Secretariats of the OECD - Nuclear Energy Agency and the International Energy Agency. The report describes the potential and trends of electricity use in OECD countries as the main parameter of nuclear power development, including oil displacement and future generation mix; gives a most recent assessment of nuclear power growth to the year 2000; deals with supply and demand considerations covering the whole fuel cycle; assesses the impact of the nuclear contribution on the overall energy situation according to three energy scenarios and the consequences of a possible nuclear shortfall and finally; reviews other factors influencing nuclear energy growth such as security of supply, economics of nuclear power production as well as public and utility confidence in nuclear power.

A combined study has been undertaken using numerical analysis and scaled physical model testing to investigate soil resistance to upwards pipeline movement. Peak resistance forces and the displacements required to mobilise these forces were investigated for varying geometries soil properties and boundary conditions using finite element analysis. These results were compared with a series of centrifuge and laboratory model tests. Soil deformation mechanisms calculated in the finite element analysis and those observed in the centrifuge model tests were compared. The role of the deformation mechanism on the load-displacement behaviour of the pipe and the failure load was also examined.

Optimisation of propeller/hull configurations based on the Reynolds-Averaged Navier-Stokes (RANS) equations has been very rare so far due to the large computational effort required. Virtually no such optimisation has been carried out at full scale where only a few RANS methods are at all applicable due to stability problems. The present paper introduces a newly developed RANS solver especially designed for stability and this solver is shown to work well at full scale. Through a link to a commonly used propeller analysis code predictions of the viscous flow around the full scale ship with an operating propeller may be made. This utilized in the work reported here where the flow codes are introduced into a system for automatic optimisation. It is shown that even well designed propellers may be further improved both in a fixed wake and in the wake behind a fixed hull.

The shedding of vortices and flow interference between two circular cylinders in a tandem arrangement is investigated numerically in this paper. The simulations are carried out for cylinders with different diameters. The upstream cylinder has a diameter twice the diameter of the downstream cylinder. The simulations are accomplished for various values of the gap between the cylinders. The Fractional Step Method is used for the simulations and the flow is assumed two-dimensional. The calculations are carried out on a three-nodded unstructured mesh. All the simulations are performed for Reynolds number equal to 200 and the flow is solved through the Finite Volume Method. The mesh is finer close to the cylinder wall in order to have a better description of the boundary layer.

The shedding of vortices and flow interference between two circular cylinders in tandem and side by side arrangements are investigated numerically in this paper for various values for the gap between the cylinders. The Fractional Step Method is used for the simulations and the flow is assumed two-dimensional. The calculations are carried out on a three-noded unstructured finite element mesh. All the simulations are performed for Re = 200 and the flow is solved through the finite-element method. The mesh is finer close to the cylinder wall in order to have a better description of the boundary-layer.

The Arctic and Sub-Arctic regions of Russia have the world's largest reserves of oil and natural gas. It seems likely that exploitation of the giant natural gas fields on the Yamal Peninsula and Yamal offshore in the Western Arctic regions of Russia will precipitate the development of Arctic LNG shipping. Therefore one of the key design issues at the conceptual and detailed design phases will be the integrity and safety of the LNG CCS(Cargo Containment System) under the accidental impact with an iceberg. With ongoing advances in computational capabilities and the sophisticated tools available such as hydrocode LS-DYNA and MSC-DYTRAN shock response analysis techniques have been developed with a viable less costly alternative as well as more reliable aid to tests and-or experiments. These simulation codes have also helped to advance full-scale ship collision analysis techniques. This study develops full-scale iceberg-ship collision analysis techniques and considers the surrounding seawater and FSI (Fluid-Structure Interaction) and MCOL (rigid ship motion program) boundary linked with the LS-DYNA code. It also establishes the structural safety assessment technique for LNG CCS. Conclusions are drawn.

The altitude and position of a submerged body being towed by a vessel is affected by wave-induced motion of the latter. To reduce this disturbance a two-part towing system is used. In this study a 2D dynamic model of the two-part underwater towing system is described. Numerical modelling of the problem was attempted. The finite difference algorithm was used to formulate the problem. A lumped mass-spring system was used for modelling the cable. The formulation for the towed body was based on Kirchhoff's equations for motion of a rigid body. For the demonstration of the model a numerical example of the tow-ship travelling in a wave field is described. Subsequently response of the towed body was simulated and is compared with the experimental values obtained from the literature.

Fundamental principles of the United Kingdom's system for National Vocational Awards (NVQ) are outlined with special reference to its adoption for basic watchkeeping certification (Level III NVQ) to the required units and specific elements which detail tasks in which the student must demonstrate competence and to the potential application of simulators for performance assessment (particularly in those tasks which would require major operational changes on board an in-service vessel). The main engine room systems available by simulation to students of the South Tyneside College are described together with the assessment criteria and methodology used and illustrative examples of assessments in two different NVQ elements (E8.1 Prepare and start up main diesel engine plant and E24b Identify faults in bridge control system): verification of the assessment procedure is also considered. Other uses of engine room simulators also considered include: staff assessment team training for emergency situations and main engine fault finding. The need for simulator realism is stressed.

Practical application of DD (domain decomposition) is limited by considerable software development costs. It is caused by the fact that to apply DD it is necessary to consider in aggregate an applied problem and its mathematical model a computational algorithm and its implementation on hardware software environment. The aim is to reduce development costs when high performance DD software is implemented. Object-oriented analysis and parallel distributed middleware are applied to the design of a software model in order to solve FSI (fluid-structure interaction) problems. The analysis framework is presented and an example is presented to demonstrate its facilities.