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The Hatchcoverless Containership Concept - Some Operational Experiences: IMarE Sydney/RINA Australian Division Joint Branch Meeting Paper Presented on 25-9-91
AuthorsD A Gillies
PublisherIMARE
AbstractThis paper reviews the operational performance of the hatchcoverless vessel `Bell Pioneer' since the original paper held on this subject in February 1989. The ship is discussed in detail with comments on operational difficulties found - mainly thawed sludge from container bottoms finding its way into the bilges.
AuthorsDate publishedD A Gillies
1991
PublisherIMARE
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Vertical ice loads on offshore structures due to changes in water levels
AuthorsS Kioka ; S Ito ; H Saeki et al.
PublisherComputational Mechanics Publications
AbstractVertical ice forces which act adversely on offshore structures are explained mathematically. Tables and figures are provided for the practical computation of the ice forces with attention given to destruction by adfreezing and bending. The procedure to calculate vertical ice forces is considered. There is a brief discussion on adfreeze bond strength and flexural strength. The effect of interaction between the ice and structures made of multiple piles is considered theoretically.
AuthorsDate publishedS Kioka ; S Ito ; H Saeki et al.
1995
PublisherComputational Mechanics Publications
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Wave-induced behaviour of a submarine pipeline laid on an erodable bottom - full-scale experiments
AuthorsW Dursthoff ; W Magda ; T Marcinkowski et al.
Date published1997
AbstractTests were carried out in the Grosser Wellenkanal (GWK) which is the large wave flume in Hannover in order to investigate the degree of wave-induced lowering of a cylinder laid on a sandy seabed. Results obtained focus on the development of erosion (scour) in the sandy bottom around the pipeline under the influence of waves self-lowering of the pipeline and its movement relative to the initial position.
AuthorsW Dursthoff ; W Magda ; T Marcinkowski et al.
Date published1997
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Assessment of Vortex Induced Vibrations on Deep Water Risers by Considering Fluid-Structure Interaction
AuthorsK Herfjord ; S O Drange ; T Kvamsdal
Date published1998
AbstractA methodology for computing vortex-induced vibrations (VIV) on risers is presented. It is based on computation of the flow by a CFD program structural dynamics by a non-linear structural (CSD) code and a coupling between them. The CFD computations are performed in 2D at a number of sections along the riser. The load is imposed on the riser in a strip theory manner. The coupling between the CFD planes takes place through the response of the riser. The local deformation of the riser is taken into account by the CFD program thus completing a fluid-structure interaction loop each time step. The methodology is validated by comparing results from simulations with results from model tests.
AuthorsK Herfjord ; S O Drange ; T Kvamsdal
Date published1998
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Atmospheric forcing impact in MOTHY oil drift model
AuthorsC Skandrani ; P Daniel
Date published2001
AbstractMOTHY (a numerical marine oil pollution transport model) is investigated. The impact of wind interpolation on the drift of pollutants is studied. Wind is interpolated from the atmospheric model grid to the ocean model grid. A comparison of two interpolation methods is investigated on both theoretical and numerical cases of pollution drift. One method is an interpolation on wind components the other is an interpolation on wind intensity and direction. It is concluded that MOTHY is well adapted and able to predict real drift of slick. However in studying its accuracy in relation to atmospheric forcing it is shown that the choice of wind interpolation type could affect the drift. Bilinear interpolation on wind density and direction is shown to be better than interpolation on wind components.
AuthorsC Skandrani ; P Daniel
Date published2001
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BMT de Beer's consolidated manual on postharvest handling, cooling and storage or fruit and vegetables
AuthorsHarm de Haan
Shelf Location230c
AbstractThis manual is a useful tool as a reference to quickly verify the recommended optimum carrying temperature, highest freezing point, acceptable maximum temperature upon loading, optimum relative humidity, ventilation rate, expected storage life at recommended temperature, climacteric or non-climacteric produce, ethylene production and sensitivity, recommendations and benefits of modified/controlled atmosphere and seasonal availability on different continents for numerous fruit and vegetables. The manual also includes information on havesting, handling, cooling/storage, mixed loads, and summarised storage disorders on individual products. It concludes with Food Storage Guidelines for Consumers.
AuthorsPublisherHarm de Haan
NPN Drukkers bv
ISBN number9789086200023
Shelf LocationDate published230c
2008
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Conflicting Views: CO2 corrosion models corrosion inhibitor availability philosophies and the effect on sub-sea systems and pipeline design
AuthorsJ Marsh ; T Teh
Date published2007
AbstractThe influence of different corrosion models corrosion availability philosophies corrosion control philosophies and standards on materials selection and corrosion allowance design criteria for sub-sea systems and pipelines are examined. These differ enormously from operator to operator and national authority to national authority. The result is that for the same nominal environmental conditions pipeline and sub-sea systems designs can vary enormously depending on who is the client and where the facility will be situated. Also it results in designs that would be deemed as entirely acceptable for operation in one area of the world but which would be considered as unsafe for operation in another. The nature of these influences is discussed as well as the effect on sub-sea system materials selection and corrosion allowance. Also discussed is the conceptual conflict between what can be designed for in theory and what experience tells us has actually been achieved in practice. Finally
AuthorsJ Marsh ; T Teh
Date published2007
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Design of a clamp-on ultrasonic liquid flowrate monitor for wet gas pipelines
AuthorsD Vedapuri ; M Gopal
Date published2000
AbstractA clamp-on ultrasonic technique to monitor liquid flow rate in wet gas pipelines for liquid volume tractions up to 10% is described. To determine the liquid flow rates two parameters are measured: liquid film height and film velocity. Special transducers based on geometrical acoustics are designed to overcome attenuation and pipe wall interference. Film velocity is determined using a cross-correlation technique. Studies are done to determine the liquid film heights and film velocities as a function of superficial gas and liquid velocities. These velocities are varied. Results are presented and discussed and conclusions are drawn. Diagrams and graphs appear on pages 306-312.
AuthorsD Vedapuri ; M Gopal
Date published2000
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Development and Verification of a 3-D Model for Ice Forces on Conical Structures
AuthorsM Lau ; J Molgaard ; F M Williams et al.
Date published1999
AbstractA new model for ice forces on conical structures is presented and its performance is assessed with a broad set of experimental data. As part of the model development previous analytical models of ice forces on conical structure have been critically assessed through comparison with experimental data. The new model development which recognizes the 3-D nature of ice load substantially improves model predictions. Furthermore the model is simple enough to be easily incorporated into a probabilistic methodology and provides a good appreciation of the important roles various parameters and processes play on ice force development.
AuthorsM Lau ; J Molgaard ; F M Williams et al.
Date published1999
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Economic impacts of changes in the population dynamics of fish on the fisheries of the Barents Sea
AuthorsP Michael Link ; Richard S J Tol
Date published2006
AbstractThe size and geographic range of fish stocks depend largely on existing hydrographic conditions which can affect fish stock population dynamics and even stock collapse. This study uses a bioeconomic simulation model to assess the economic impacts that a sudden change in the fish population dynamics would have focusing on the Barents Sea cod and capelin fisheries. The model covers a time period of a century and looks at the economic effects of changes in the population dynamic of fish stocks namely the intrinsic rate of production and the environmental carrying capacity. Cod and capelin fisheries were chosen because the cod fishery is of great economic importance in Norway and capelin are one of the main food sources of cod. Therefore changes in the Barents Sea capelin stock would have an effect on the cod stock as well.
AuthorsP Michael Link ; Richard S J Tol
Date published2006
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Effect of width of bay mouth on water exchange in stratified semi-closed bay
AuthorsKoji Asai ; Syusaku Miyawaki ; Fumihiko Yamada et al.
Date published2002
AbstractSemi-closed bays or water areas enclosed by dikes suffer from water quality pollution frequently since an ability of water exchange in semi-closed bays is poor. Many researchers and engineers have proposed methods to improve water exchange in a semi-closed sea. However these experimental investigations were carried out using homogeneous fluid. The water exchange in homogeneous fluid depends on only a horizontal current since a vertical tidal current is very small due to barotropic pressure. On the other hand if a buoyancy effect exists the vertical tidal current is not negligible. Therefore not only the horizontal tidal current affects the water exchange but also the vertical tidal current. It is important to study the effect of a shape of a bay mouth on water exchange under stratified fluid conditions. However it is quite difficult to carry out a model experiment for tidal water exchange with stratified fluid.
AuthorsKoji Asai ; Syusaku Miyawaki ; Fumihiko Yamada et al.
Date published2002
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Experimental study on a self standing hybrid riser system throughout tests on a deep-sea model basin
AuthorsPaulo S D Pereira ; Katsuya Maeda ; Celso K Morooka et al.
Date published2005
AbstractThe present paper introduces a concept of a hybrid riser Self Standing Hybrid Riser (SSHR) particularly in development for ultra deepwater around 3000 metres. The main problems faced in the initial definitions for design of such risers in the above scenario are discussed. A unique laboratory test with reduced model carried out in waves current and riser top oscillation experiments in a very deepwater wave tank is shown. Also experimental results are shown and discussed especially considering difficulties faced to carry out this experiment. Discussions are addressed in terms of vortex induced vibration (VIV) around buoyancy can riser line pipe and flexible jumper.
AuthorsPaulo S D Pereira ; Katsuya Maeda ; Celso K Morooka et al.
Date published2005
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Experimental study on a spread catenary mooring for FPSO
AuthorsRiccardo Codiglia ; Giorgio Contento ; Fabrizio d'Este et al.
Date published2002
AbstractThe main results of experimental tests are presented which were carried out to analyse the behaviour of a proposed mooring system for FPSO that is well suited for weather conditions characterised by a dominant swell and current and by a moderate almost perpendicular local sea and wind. The basic idea of this mooring design is to join the best characteristics of the turret and spread mooring systems to allow the FPSO to move within a specified offset so that the wave loads on the lines and on the vessel can be minimised. The experiments and the related analysis refer to the dynamic behaviour of the FPSO alone and FPSO+Shuttle tanker during offloading in extreme and operational weather conditions respectively. In the case of the FPSO+Shuttle tanker the tension on the hawser is also analysed.
AuthorsRiccardo Codiglia ; Giorgio Contento ; Fabrizio d'Este et al.
Date published2002
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First Joint ISSC/ITTC International Workshop Proceedings: Uncertainty Modelling for Ships and Offshore Structures (UMSOS)
AuthorsS Hirdaris (ed.)
PublisherISSC, 2012
AbstractProceeding of the First Joint ISSC/ITTC International Workshop Proceedings International Towing Tank Conference 8th September 2012, Rostock, Germany Uncertainties of environmental description Dr. Elzbieta Bitner Gregersen, Dr. Kevin Ewans, Dr. Michael Johnson - ISSC Committee I.1 on Environment Uncertainties related to predictions of loads and responses for selected offshore and coastal structures Prof. Wei Qui - ITTC, Ocean Engineering Committee Uncertainties in the prediction of loads and responses for ships and offshore structures Presentation 1 : Dr. Spyros Hirdaris and Prof. Apostolos Papanikolaou - ISSC Committee I.2 on Loads Prof. Jeom Paik - ISSC Committee III.1 on Ultimate Strength Dr. Fai Cheng - ISSC Committee IV.1 on Design Principles and Criteria Dr. Ingo Drummen, Dr. Michael Holtmann - ISSC Committee II.2 on Dynamic Response Uncertainties related to seakeeping experiments and related load and response procedures Prof. Yonghwan Kim - ITTC, Seakeeping Committee Uncertainties and Reliability analysis for ships and offshore structures Prof. Purnendu Das - ISSC Committee III.1 on Ultimate Strength
AuthorsDate publishedS Hirdaris (ed.)
2012
PublisherISSC, 2012
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Force/flow measurements on a low-speed vectored-thruster propelled UUV
AuthorsK D von Ellenrieder ; L E J Ackermann
Date published2006
AbstractForce/torque and particle image velocimetry measurements are conducted on a vectored-thruster UUV model in a water flume. The aims are to determine the hydrodynamic drag lift and moment coefficients acting on the vehicle hull for zero rudder angle and yaw angles up to thirty degrees and to measure the magnitude and direction of the thrust produced with the vehicle at a yaw angle of zero degrees and rudder deflection angles of up to thirty degrees. While the measured drag coefficient is higher than predicted by theory the hydrodynamic coefficients data are expected to be useful in predicting the response of vehicles in the field. Additionally the magnitude of the thrust vector varies nonlinearly with rudder angle and for nonzero rudder angles the thrust vector does not point in the same direction as the thruster. PIV images reveal that at rudder deflection angles of twenty five and thirty degrees the flow upstream of the propeller inlet has separated from the tail section and impinges at a large angle to the tail thereby reducing the thrust deflection angle and the total yaw moment acting on the vehicle.
AuthorsK D von Ellenrieder ; L E J Ackermann
Date published2006
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Foundation behaviour of a giant gravity platform on soft soils as evidenced after ten years of monitoring
AuthorsGeir Svano ; Eiliv Skomedal ; Hans Petter Jostad et al.
Date published2007
AbstractThe Troll A platform in the Norwegian trench rests on a huge GBS (gravity-based structure) with 36 m-deep concrete skirts. The GBS was installed by skirt penetration into a seabed of normally consolidated clay in May 1996. A comprehensive structural and environmental monitoring system has provided large amounts of data on foundation and structural performance since platform installation and is still operative. The monitoring showed unexpected pressure response in 2002 and triggered a comprehensive study including foundation behaviour from installation until today. Here firstly the monitoring system is presented with emphasis on the foundation instrumentation. Next selected pressure histories are shown and the settlement history of the foundation is discussed. After this the pressure history is analysed using a theoretical approach. Finally the learning after the pressure bleed down period is presented.
AuthorsGeir Svano ; Eiliv Skomedal ; Hans Petter Jostad et al.
Date published2007
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Groundwater nutrient dynamics on a barrier island in the northeast Gulf of Mexico
AuthorsD Reide Corbett
Date published2001
AbstractGroundwater discharge provides significant amount of nutrients and contaminants into some coastal zones. In areas with a shallow freshwater system groundwater may easily be contaminated from OSTDS (onsite sewage treatment and disposal systems) which are typically installed less than 1 m above the water table and may be flooded during heavy rains. The transport of non-point source pollution from OSTDS to shallow groundwater and ultimate discharge to surface waters could be an important source of contamination to the marine environment especially in areas of restricted circulation such as an estuary or small embayment. Although this pathway is becoming better known scientists and coastal managers alike still largely ignore it. When evaluating impacts from OSTDS on coastal waters it is important to consider the natural flux of nutrients in order to implement sound management strategies. The groundwater nutrient dynamics on a barrier island in the northeast Gulf of Mexico is examined. Methodology is described. Nutrient results show that the most efficient OSTDS on the island would be an aerobic system that was raised above the natural land elevation by approximately 1 meter.
AuthorsD Reide Corbett
Date published2001
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Handbook on repair- and maintenance welding on board (Handbook for Maritime Welders)
AuthorsUNITOR
Shelf Location232a
AbstractThis book covers the topics of welding instruction available from Unitor, gas distribution, welding gases, gas cylinders, decomposition of acetylene, central plant for acetylene and oxygen, gas welding equipment, welding and cutting equipment, types of joint, gas welding and brazing, filler materials for gas welding, brazing and soldering, filler materials for brazing and soldering, fluzes, thermic spraying, electric arc welding and power sources, permanent cable installations for welding current, electrical connecting components, personal protection equipment, safety regulations, electrodes, filler materials for electric arc welding, electrodes for various welding jobs, the air-arc process, underwater welding and cutting, TIC welding equipment, metal identification and what melds what.
AuthorsPublisherUNITOR
Oslo : Unitor Ship Services
Shelf LocationDate published232a
1980
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Increasing the battery voltage on a nuclear submarine
AuthorsJohn M Lee ; David Faulkner ; Peter Rowlinson
Date published2010
AbstractThe main battery on a nuclear submarine provides an air-independent back-up source of power while the submarine is submerged and provides power to the main DC system to enable the submarine to get back to the surface should the output from nuclear plant fail. As the submarine main DC system is connected directly to the battery the choice of battery technology will have a direct bearing on the main DC system voltage. Whatever nominal DC voltage and battery technology is chosen there will be a voltage range governed by battery charge or discharge rate and the state of charge. All equipment connected to the DC system will have to operate over this voltage range. This paper considers the influence that the choice of battery technology will have on the DC voltage selected. Options are considered and conclusions drawn.
AuthorsJohn M Lee ; David Faulkner ; Peter Rowlinson
Date published2010
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Influence of axial force and initial curvature on the flexural deflection of Euler-Bernoulli beam structures solved by DQEM using EDQ
AuthorsChang-New Chen
Date published2005
AbstractIn modern engineering design it is frequently necessary to analyse the influence of axial force and initial curvature on the flexural deflection of Euler-Bernoulli beam structures. This analysis is achieved by the DQEM (differential quadrature element method) using EDQ (extended differential quadrature). The DQEM uses differential quadrature to discretise the governing differential equation defined on each element the transition conditions defined on the inter-element boundary of two adjacent elements and the boundary conditions of the beam. Numerical results solved by the developed numerical algorithm are presented. The convergence of the developed DQEM analysis model is efficient. The theory presented can be used effectively to obtain accurate results in analysing the offshore structures.
AuthorsChang-New Chen
Date published2005