Special Ships Research Articles

Historical perspective on the structural design of special ships and the evolution of structural design methods

Recent decades of ship design and construction have produced numerous examples of innovative and special-purpose hull forms, structures, speeds, size and complexity. These include progressively larger container ships, ultra-large crude carriers and cruise vessels, liquefied natural gas (LNG) carriers, high-speed catamarans, small-waterplane-area twin-hull (SWATH) vessels, trimarans and others. The geometries, structural topologies and materials required for these vessels did not fit well with traditional design methods and procedures, rooted in empirical approaches. Instead, these ships and their structures required some form of direct analysis or first-principles approach, which by its nature is computer based. The ship design and design approval community responded to this new set of requirements by developing and implementing new procedures, new methods and new technologies to adequately address the need for first principles in the design. This design methodology innovation in turn placed new and significant demands on the state of the design software environment under which the new methods and procedures were being developed. This paper traces some of the innovative ship types that have evolved over recent decades and the associated computer-based structural design technology evolution during this time. In particular, the innovations of Professor Owen Hughes in establishing a first-principles approach to ship structural design, documenting the theoretical basis for this approach in the textbook Ship Structural Design: A Rationally-Based, Computer-Aided, Optimization Approach, and developing the MAESTRO computer-based implementation of the methodology are presented

AGaPaS - a new approach for Search-and-Rescue-Operations at sea

An innovative, satellite-guided Search-and-Rescue-System is under development. This system utilises an autonomously acting rescue vessel to salvage a person overboard to increase significantly the chance of survival. It was developed to be used on special ships or offshore platforms, where workers have to act in bad weather conditions and often going overboard of a person will be discovered too late.A substantial challenge is the automation of the autonomously acting rescue vehicle as well as the integration into the superior Search-and-Rescue-Process. The developed cascaded control concepts were designed to ensure the fastest possible approach to the casualty without endangering the person. Therefore, two degrees of freedom control concepts are used to separate the reference values from the disturbances. The inner speed control structure is divided into two parts and consists of the control structure itself with an in-line allocation to the device configuration.The paper mainly addresses the automation of the rescue vessel, the synthesis of the control system of the autonomously acting vehicle as well as the integration into the superior Search-and-Rescue-Process. Additionally, some test result of this complex system are shown at the end of the paper.

Floating hospitals and hop-pickers: Bjn 100 years ago

An interesting paper was published in the BJN on 31 July 1909, about the use of special ships as fl oating hospitals. In the summer of 1873, New York suffered a spell of hot weather so severe that the editorial staff of a large daily newspaper decided to take some of their newsboys for a day trip on a barge. The benefi cial results were so obvious that it was decided to continue the trips each year thereafter. While on one of these trips, a paper boy mentioned that although it was great fun, it was a pity his mother and sick baby brother could not also come along. This remark started the practice of taking mothers and babies, and soon the old excursion vessel was swapped for a special ship; fully equipped as a hospital to care for day patients:

Some measures for towing resistance decreasing of semi-submersibles in water and in ice

The semi-submersible rigs can be transported to the place of working from the place of building by special ships. But some very big rigs or semi-submersible ships can be towed afloat, at the draft above upper deck of under-water pontoons. Growth of the distances between places of building and working of semi-submersible rigs means growth of the time and the expenses for their towing, and sufficient losses of drilling time. And, sometimes a more or less long travel between two places of working at drilling draft can be needed too. Some measures for towing resistance decreasing are recommended on the basis of model tests and comparable calculations. Now that the drilling places of rigs have moved to northern seas, it means more possible action of ice on the towed and/or standing rig. But today rig columns are not sufficiently intended for counteraction with ice. Some measurements for decreasing of towing resistance in ice are recommended too.

Design Of Special Ships Equipped With Non-conventional De-oiling Equipment For Cleaning Oily Ship's Waters And Removal Of Oily Spills

Design Of Special Ships Equipped With Non-conventional De-oiling Equipment For Cleaning Oily Ship's Waters And Removal Of Oily Spills

Prospects for intercontinental seaborne transportation of hydrogen

Large quantities of hydropower are available in many parts of the world which are separated from Europe by the sea. The production of hydrogen by electrolysis using hydro-electricity is the cleanest way to obtain an energy supply to Europe, but hydrogen, after liquefaction, must be transported by ship. Various types of special ships for liquid hydrogen transportation are investigated and compared. The corresponding transportation costs are calculated and some possible solutions for the boil-off problem are proposed.

Criteria for Capacity Certification of Dry Docks and Significance of Classification and U.S. Navy Standards as They Affect Ship Safety

Extremely expensive and sensitive warships as well as valuable merchant ships are being docked in a wide variety of dry docks, many of them not originally built for the modern vessels and often operated by crews with very rudimentary training and experience and with limited engineering backup. Only since 1973 has Lloyd's Register of Shipping had published rules for steel floating dry docks, and the ABS rules were created only very recently. Following the example of the 5th Naval District, NAVSEA in Washington started the MIL-STD-1625 code using very limited personnel and funds to prepare a dry dock certification program to attempt to insure ship safety in all docks. It is a serious mistake to think that certification is a cure-all. Adequate qualification of the docking crew is just as important, including skill in dealing with special problems with special ships.

Design of the SCA Special Ships

During 1965–68 the Swedish forest products company Svenska Cellulosa AB (SCA) developed and put into operation a new distribution system for its central European and U. K. export production totalling about 800,000 tons annually. Principal features of this system included a new distribution organization, concentration of transportation between five new central terminals, and development of specialized means of transport including ships, terminal equipment, and inland subsystems.

Leading position of shipyards in the building of special ships

Leading position of shipyards in the building of special ships

Land and sea transportation of very heavy power-station equipment

The constant challenge in power technology is to increase output and, at the same time, to reduce both the capital cost and the running cost of the plant installed, thus keeping the cost of energy to the consumer as low as possible. An unremitting effort has been necessary to provide transport facilities for the larger units which have been developed, and, indeed, throughout the whole period of the development, progress has very much depended on the increase in the size and weight of the units that could be moved from works to sites. By the early 1960s the load-carrying capacity was stretched to the limit, and new methods of carrying had to be devised if further development of plant was not to be restricted. The paper describes the novel methods of sea and land transport which have been developed to enable larger, single units of plant to be delivered to power-station and substation sites than has heretofore been possible in Britain or, with very few exceptions, in any other country in the world. The new facilities will enable major savings to be made in construction and operating costs of new power installations and will enable manufacturers to improve their competitive position in the export market by being able to build the largest units more economically than heretofore. The characteristics of the two special ships now in operation are outlined, the philosophy of design and alternative solutions are examined, and the reasons are given for evolving the type selected. The development of the air-cushion equipment now in use for attachment to road transporters to reduce the stress on highways and bridges is described, and its advantages are set out. The development of a prototype vehicle for off-the-road use over ground such as pasture and plough land to aid access and minimise damage during construction of electricity-transmission works is also set out. The paper concludes with a description of the development of a prototype multiple-wheel assisted-lift road transporter for heavy plant as a possible alternative to the air-cushion equipment under certain conditions.

Shoreside Facilities for Special Purpose Ships

History and current situation regarding special purpose vessel operations and proposed ship construction program, layout and design criteria; technical analyses covering roll-on roll-off, lift-on lift-off, container, and conveyor terminals for trailer berths and pier facilities, transfer bridges, receiving and delivery areas.

The future of world magnetic surveying

The secular geomagnetic variation necessitates continual repetition of world magnetic surveying. Since iron ships displaced wooden ones, ocean magnetic surveying requires special non-magnetic ships; it practically ceased when the Carnegie was lost in 1929, and the subsequent secular geomagnetic changes are imperfectly known. Magnetic surveying is slow; one ship or one land party makes measurements at only one or two stations daily. These stations may not be representative of the area over which they chiefly determine the local course of the isomagnetic lines on the charts. In drawing the charts, some well-defined smoothing process is desirable; continuous magnetic measurements along a world network of lines would best serve this purpose. If such records could be made on aeroplanes, a world magnetic survey might require only two or three years; research into this possibility is desirable.