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Research into current interactions within an array of buoyancy cans top-tensioned risers (WHB risers array configuration) is presented. This research includes an extensive test campaign in a large-scale current channel and is aimed at providing understanding of both the quasi-static behaviour (mean inclination due to drag forces and mask effects) and the fluid-structure dynamical interactions (VIV (vortex induced vibrations) and WIV (wake-induced vibrations)). Preliminary numerical analyses are carried out with DeepLines (FEM) and DeepFlow (CFD) software in order to validate specific modeling principles and similitude rules suitable for these particular model tests. The risers array model focuses attention on the buoyancy cans motion to check clearance issues. Three main parameters are tentatively reproduced at model scale: the riser deflection under drag forces; the reduced velocity governing the occurrence of VIV; and the reduced damping governing the dynamic response amplitude. The risers array is tested under various current incidence and for a wide range of current (and reduced) velocities. Mask effects are quantified and equivalent drag coefficients for each riser of the array are identified as a function of the current incidence.

The UK MoD has a clear commitment to ensure that the risks to its employees and the public that are associated with its activities are controlled in a manner that is at least as good as that required by a national statute. For the warship this policy has been implemented by applying JSP 430 which requires the development of a safety case and certification in accordance with Naval Authority Regulations which themselves include the requirement to satisfy civil regulations where applicable. The implementation of JSP 430 on recent major platform projects has involved significant effort by the safety teams in order to provide the necessary justifications that the risks associated with the operation of the platform are broadly acceptable or Tolerable and ALARP. With the current movement to procure warships in accordance with Classification Society Codes for Naval Vessels the prescription provided by these rules goes some way to provide the necessary assurance that a platform is safe to operate in a military environment. However this approach does not address all aspects of safety on a naval platform and hence it is argued that there still needs to be a degree of risk-based assurance the level relevant to the military function of the platform. The paper proposes a framework for reducing costs of warship safety assurance by making the best and most cost-effective use of civil approaches without compromising military capability. It is attempted to identify the areas of safety case development activity that have represented the most significant workload in the development of major platform safety cases.X36294 Cost-effective solutions for innovative applications

The -re-1990 America's Cup races have created widespread interest in the highly developed 12-meter yachts. This also extended to the enthusiasts of R-C (radio-controlled) model sailboat racing. The production of hull for R-C racing started as early as 1968. A one-design class later evolved and was organised around the Morgan design and became known as the EC-12M (East Coast 12-metre) class yacht. Since the class was organised in 1971 a number of manufacturers have been authorised to produce EC-12M hulls from the Morgan-related plugs. As with many 'one design' yachts over time the hull manufacturers of the EC-12Ms began a series of subtle variations intended to improve the sailing performance as they sold the newer hulls yet still within the class rules. Some of the one-design fleet problems began to surface for the EC-12M as the newer hulls were built in the late 1980s. The hulls varied slightly but in significant ways. To answer these questions it was necessary to use a test method which would be relatively simple non invasive and reasonably accurate in order to determine both the radius of gyration and the location of the CG. Comparative evaluations were carried out using a Lamboley pendulum test to determine the radius of gyration in the pitch axis and to locate the centre of gravity of the EC-12M model sail yachts. The Lamboley simultaneous equations were solved using a computer programmed for this purpose. From these data the righting moment at 20 degrees heel and the moment of inertia in the pitch axis without the rig were calculated and plotted. Critical pitching frequencies were calculated assuming a nominal mast and rX38868

The long-term trend in demand for energy resources means that the Arctic will remain the focus of development plans in many organisations. The rise in resource-related projects has created the need for new approaches to assessing and minimising risk. The new tankers and drill ships required for the Arctic will be larger and stronger than any previous ships but will be very carefully designed and operated. This paper presents a methodology for assessing risk to large Arctic ships in a variety of scenarios. For the purpose of illustration fo the approach two ice collision scenarios are described. One is the case of a large ship with a bulbous bow hitting an iceberg head-on. The other is an aft waterline collision with a sea ice floe. Both scenarios are outside the conditions formally considered in standard ice class rules but are significant issues. The paper provides owners designers and regulators with an example of a methodology to examine ce loads using a rational set of design scenarios. The results show that vessels can easily be operated in a manner that can create dangerous load levels. The results are directly relevant to the structural design of new large Arctic tankers (oil and LNG) and large Arctic drill ships. The second part of the paper presents some initial results from consideration of plastic structural response to moving ice loads. The significance of the movement (sliding) of the load increases as the response level increases.

Zeke's Island part of the North Carolina National Estuarine Research Reserve is an undeveloped site. The Reserve site is owned by the State of North Carolina and managed by the North Carolina Department of Environment and Natural Resources Division of Coastal Management as part of the Coastal Reserve Program. State statutes and rules allow compatible recreational uses and other activities on the Reserve. Although a fairly pristine and isolated reserve site the Zeke's Island Reserve is located near the communities of Wilmington Carolina Beach and Kure Beach. These communities attract significant numbers of in-state and out-of-state tourists and local residents each year. Many of these tourists and residents choose to recreate on the Zeke's Island Reserve due to its less crowded undeveloped character and nature. The effects of various recreational activities are investigated in a study. Based on the results it is concluded that the passive use of regulatory signs is an effective management tool in regulating visitor behavior within the Zeke's Island Reserve.

The book is based on 'Practical Yacht Construction' by C.J. Watts but is a revision due to the changes covering the whole field of yacht construction. It uses the original framework. Chapters 1 and 2 cover construction of keel, hull, decks and other parts but includes glues for main structural members and of plywood for decks, changes in metal fastenings etc. Chapter 3 covers engine seating, anchor arrangements, davits, cavils, stern chocks or archboards. Chapter 4 covers masts and rigging, with changes from gaff rig to the more efficient Bermudan rig and the introduction of aluminium masts, stainless steel standard rigging etc. Chapter 5 covers joinery work, plumbing, heaters, steering, ventilation, electric equipment and auxiliary propulsion. Lighter, more efficient joinery, better plumbing systems, plastic piping and improved ventilation have been introduced. Chapter 6 covers Thames tonnage, inside ballast, general arrangement, winches, pulpits and other fittings. Chapter 7 deals with the emergence of the glass-reinforced plastic hull, covering materials, moulds, methods of construction and notes from Lloyd's Rules repairs. The final chapter covers the introduction of special ship building alloys and a comparison with more traditional steel or timber construction.

The procurement of Naval Ships has changed dramatically over the last 20 years with the demise of Naval Dockyards as they have been privatised in many countries with the loss of the traditional naval overseer and the move to Prime Contractor managed procurement projects. included in this has been the growing use of Classification Societies to provide an assurance process for the navy both during procurement and perhaps more importantly through the long service life that a naval vessel must provide. Lloyd's Register has been as the forefront of supporting this transformation in the development of specific Classification Rules for Naval Ships and has worked with many navies in recent years both for new and existing vessels. in order to get the best value from the transformation of navla procurement that has occured changes in approach from the traditional process have been necessary and there is a need for personnel involved with procurement acceptance and operation of the vessels through life to understand the impact the transformation brings with it. These issues will be discussed and considered in the context of the need for many different procurement models to be available to suit a particular project but also consider some of the common problems that navies face and how they can be addressed.

UK Naval vessels have traditionally been constructed in accordance with the UK MoD's own standards and specifications. However the requirement to meet today's expectations for safety assurance has led the UK MoD to develop Naval Authorities responsible for the development of regulations and the subsequent audit of submissions for certificates of safety in defined 'key hazard' areas. There has also been an increasing movement towards the procurement of warships constructed in accordance with class rules developed specifically for naval vessels. Work is described that was undertaken by BMT Defence Systems Ltd and Lloyds Register on behalf of the UK MoD to determine the level of confidence provided to the Propulsion and Manoeuvring Systems Naval Authority by a vessel being maintained in either commercial or naval class. The objective was to identify any gaps between the risk-based requirements of the Naval Authority Regulations for Propulsion and Manoeuvring Systems and the deliverables provided by Naval Classification Services. The outcomes were to provide guidance to the Naval Authority as to what extent Naval Classification provides assurance that the 'key hazard' area is fully mitigated and to provide advice on the extent of material state verification required by the Naval Authority against that provided by the commercial procurement model. The work concludes that the regulatory approach can provide a significant contribution to the Safety Case approach and provides a pragmatic demonstration94739 Assurance of digital control accuracy at non-centralized stochastic actions J Ladisch ; B P Lampe ; E N Rosenwasser et al.

This book is intended both as reference book and vital source of new ideas. It offers a thorough explanation of all disciplines related to the field. Employing a fictional case history technique, the book traces the course of a government procurement for a simulated radar system. We view the project chief’s role from the time the invitation to bid is received through the execution of the contract and the ultimate equipment acceptance. In fact, you’ll see every major technical and administrative factor with which today’s project engineer must be familiar. The book: - Presents the responsibility and authority vested in the project engineer or manager to enable you to achieve the technical, delivery, and monetary objectives - Demonstrates the analysis of alternate system designs to determine the approach which serves the best interests of the company and meets the procurement requirements - Equates the procurement requirements against company resources to establish whether participation risks are consistent with profit and other objectives - Outlines the guidelines and approaches for proposal preparation, citing factors to be included to enhance customers’ favourable evaluation - Discusses contract scheduling, covering the description of deliverable items, dates, and special provisions - Covers techniques and factors to be considered when deriving cost estimates for proposals and other purposes - Identifies types of contracts, their commonly used clauses, and the techniques and ground rules of negotiation - Goes over the legal impact and significance of a project engineer’s conduct, actions, and decisions - Explains the principles of PERT and other management tools, including reporting methods such as Line of Balance - Presents the principles of configuration management, including baselines, phases, control, and accounting - Covers project monitoring, quality control, and test and checkout stages - Presents the analysis of memory, speed, and accuracy requirements which determine the selection of a digital computer for a particular application - Discusses contract side-items, such as manuals, reports, and spares - Covers the post-delivery follow-up phase, including discussion of residual items and post-acceptance problems.

To mitigate the impact of consequences of ship collisions in terms of health, safety and the environment, it has been made mandatory that hull structures of all oil tankers have double sides and double bottoms. In recent years, International Association of Classification Societies (IACS) has developed Common Structural Rules (CSR) for structural design of double-hull oil tankers on the basis of limit states, together with the traditional approach of using the allowable working stress that has been the basis of pre-CSR. The application of CSR may result in some differences in terms of structural performance, among other aspects. The main objective of the present paper is to investigate the structural performance of CSR-designed tankers associated with ship collisions. This aspect might be interesting, although CSR are not intended specifically to improve collision performance. As an illustrative example, an AFRAMAX-class double-hull oil tanker structure with he same deadweight designed by both pre-CSR and CSR methods is studied by comparing their collision energy-absorption capabilities as obtained by nonlinear finite element methods. It is found that the collision performance of the CSR design could be improved by 5% to 25% compared with that of the pre-DSR design, depending on the accidental limit state criteria. However, it is concluded that the strength performance of the CSR vessel is similar to that of the pre-CSR vessel in terms of collision-accidental limit states, considering the uncertainties invloved in conjunction with the collision scenarios and nonlinear finite element method modeling techniques. Although the present study deals with some very specific scenarios of collisions, the insights and conclusions developed will still be useful for recognizing a structural design trend related to collision-accidental limit states.

It is shown here how poor understanding of SA (Situational Awareness) together with a lack of transfer of CRM (Crew Resource Management) knowledge into skills and a poor understanding of HF (Human Factors) concepts can very rapidly affect a situation turning it from a normal situation into a highly dangerous one without team members becoming aware of the change. It is also shown how such a risky situation could easily have been avoided and managed safely just by applying some well-known rules. A real incident is presented (anonymity preserved) in which a particular relation between the CRM training that officers received their HF knowledge and how they managed the level of SA all impacted on the final outcome. It is observed that no matter how good the training provided is this will only contribute 50% to the safety pathway. The remaining 50% will only be achieved by ensuring the transfer of the knowledge received into practical skills and that task can only be completed on board ships by reinforcing the CRM concepts the HF knowledge and enhancing SA during daily operational activities. In order to ensure this happens a two-part strategy is recommended. The first part is to twice accompany each vessel in order to coach and mentor bridge-teams underway with regard to CRM HF and SA; and to deliver refresher training to address the gaps identified. The second strategy is to provide CBT (computer-based training) to the fleet which emulates realistic voyages and provides educational CRMX44701

Contents also available online http://www.lr.org/sectors/marine/Researchandtechnology/ 1. 250 Years of Marine Technology Development. Vaughan Pomeroy. 2. Shipyard Fabrication and its Quality Control: Some Problems and Solutions. David J Howarth and John Durkin. 3. Ultimate Strength of Ship Structures. Shengming Zhang and Imtaz Khan. 4. Ship Loads: Current Developments and Future Directions. Spyros Hirdaris, Nigel White, Negin Angoshtari, Mike Johnson, Yongwon Lee and Norbert Bakkers. 5. Recent Developments in Fatigue. Alex Johnston, David Howarth, Helena Polezhayeva, Jimmy Tong, Sai Wong, Clive Badger and Tom Ward. 6. The Acoustic Emission Technique: Application to Marine Structures and Machinery. Len Rogers and John Carlton. 7. The Formation of Freak Ocean Waves. William Bateman. 8. Reflections on Copenhagen: Marine Greenhouse Gas Emissions. Anne-Marie Warris and Zabi Bazari. 9. Trainee Engineer Lecture Validation of the Design Temperatures Used in the Provisional Rules for the Winterisation of Ships. Charlotte Vie of Cambridge University. Winner of the 2010 Trainee Engineers’ technical paper competition. 10. Ship – Ice Interaction. Andrew Smith and Robert Bridges. 11. SOLAS 2009 Stability Requirements: Implementation. Jane Dodman. 12. Failures of Medium Speed Diesel Engines and Machinery. Peter Filcek. 13. The Simulation of Cavitation Erosion under Laboratory Conditions. Reddy Devalapalli, Dalibor Vlaši´c, Colin Waylen and Constantinos Zegos. 14. Advanced CFD Techniques Applied to Practical Ship Problems. Dejan Radosavljevic and Stewart Whitworth. 15. System Design and Integration. Vaughan Pomeroy, Bernard Twomey and Renny Smith. 16. Nuclear Propulsion of Merchant Ships – Aspects of Risk and Regulation. John Carlton, Vince Jenkins and Bob Smart. 17. Trainee Engineer Lecture Kite Assisted Propulsion: Fiction or Reality? – A Class Perspective, Tristan Chapman, Marine Surveyor and former Lloyd’s Register Graduate Trainee, Southampton University. Runner-up in the 2010 Trainee Engineers’ technical paper competition. In addition to the seventeen papers above, two guest speakers also delivered lectures at this year's Technology Days: 1. Technical Needs of a Ship Owner from a Classification Society. Robert Thompson, First Deputy Managing Director, UNICOM. Cyprus. 2. Technical Needs of a Shipbuilder from a Classification Society. Mr. C.H. Park, Senior Executive Vice President, Samsung Heavy Industries. South Korea.

A thorough fatigue assessment of two FPSOs was carried out using current class rules. While for the majority of the hull structure the fatigue design approach used produced satisfactory results at the cross tie beam located at frames in the wing tanks the fatigue assessment was considered unreliable. This was evident during the conversion stage because a large number of cracks were found in welded joints of the cross tie beams during the hull conversion inspection. A simplified finite element analysis (FEA) showed that the location where the cracks were found was subjected to high cyclic loads during the operation as an oil tanker and that these loads would be also severe during the FPSO operation. Further FEA was carried out in order to estimate the hot spot stresses at the affected welded joints. The additional fatigue assessment showed that the fatigue design approach used needed to be modified to firstly explain the cracks found in the component secondly to allow for a reliable and conservative estimation of the remaining fatigue life for the cross tie beam after repair work was carried out. The resultant fatigue approach adopted showed that the cross tie beam would not survive the 20 years design requirement of the project unless modifications on the local structural design were undertaken or welded joint fatigue enhancement techniques were applied to the welded joints. To resolve the problem the project decided to adopt a controlled arc welding repair of all cracked joints followed by careful inspection and application of burr machining of weld toes as a fatigue enhancement t97702 Structural integrity assessment of critical components of converted FPSO hulls Carlos A Bardanachvili ; Alexandre M Pope ; Roberto O Goulart et al.

Wave-induced vibrations often referred to as springing and-or whipping increase the fatigue and extreme loading in ship hull girders. Both effects are disregarded in current ship rules. Various numerical codes exist for predicting the wave induced vibrations but so far they are not considered reliable. Another means to investigate the importance of the high frequency response although more resource demanding is to carry out full-scale measurements and-or model tests. Recently full-scale measurements of blunt ships have been carried out by DNV and in this paper one of these ships was considered and tested in a towing tank to evaluate the additional fatigue damage due to the wave-induced vibrations. Different excitation sources may excite the 2-node vertical vibration mode depending on ship design and it is not straightforward to determine which is more important. The relative importance of the excitation mechanisms are investigated by two approaches. The first separates the whipping from springing to illustrate their relative importance based on basic theory in combination with model test results. The linear and second order transfer functions are used in this procedure. The second deals with the effect of the bow design on the additional fatigue damage. Three different bows were tested. The first bow design is identical to the real ship. The second bow design is a simplified version of the first one by removing the bulb and flare. The third bow is fundamentally different from the two former blunt bows. Bow three is sharp pointed with a vertical sharp stemX44934 The effect of bowshape on the seakeeping performance of a fast monohull