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There is at present great interest in large ships capable of carrying substantial cargo at speeds in excess of 40 knots. At the same time, there are large gaps in our understanding of the hydrodynamics, structural engineering, and economics of high-speed vessels. Monohulls, catamarans, trimarans, surface effect ships, and air cushion vehicles are considered in the present work. The total resistance of these vehicles is divided into separate components which are estimated using different methods. Skin-friction is estimated using Grigson's algorithm which gives much better predictions of flat plate skin-friction than the traditional ITTC method. Wave resistance of displacement hulls is estimated using Michell's thin-ship theory: a similar theory is used for the wave resistance of travelling pressure distributions. Several simple formulae are derived that can be used in the preliminary design stage of catamarans to estimate optimum demihull separation. Memetic algorithm techniques are used to find vessels with minimum (calm-water) total resistance. Optimal geometric parameters are found for vessels of 1200 tonnes under a variety of geometric limitations and constraints on upright stability, at design speeds of 50 knots and 75 knots. Estimates are made of the principal weight components of the optimal vessels. Empirical formulae for the efficiencies of powerplants and propulsors then enable estimates to be made of the maximum range, the cargo capacity, and the fuel consumption. / Thesis (M.Sc.)--School of Mathematical Sciences, 2005.

Thesis (Ph.D.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 187-194.

Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Fotis Papoulias. Includes bibliographical references (p. 73). Also available online.

There is at present great interest in large ships capable of carrying substantial cargo at speeds in excess of 40 knots. At the same time, there are large gaps in our understanding of the hydrodynamics, structural engineering, and economics of high-speed vessels. Monohulls, catamarans, trimarans, surface effect ships, and air cushion vehicles are considered in the present work. The total resistance of these vehicles is divided into separate components which are estimated using different methods. Skin-friction is estimated using Grigson's algorithm which gives much better predictions of flat plate skin-friction than the traditional ITTC method. Wave resistance of displacement hulls is estimated using Michell's thin-ship theory: a similar theory is used for the wave resistance of travelling pressure distributions. Several simple formulae are derived that can be used in the preliminary design stage of catamarans to estimate optimum demihull separation. Memetic algorithm techniques are used to find vessels with minimum (calm-water) total resistance. Optimal geometric parameters are found for vessels of 1200 tonnes under a variety of geometric limitations and constraints on upright stability, at design speeds of 50 knots and 75 knots. Estimates are made of the principal weight components of the optimal vessels. Empirical formulae for the efficiencies of powerplants and propulsors then enable estimates to be made of the maximum range, the cargo capacity, and the fuel consumption. / Thesis (M.Sc.)--School of Mathematical Sciences, 2005.

Thesis (M.Eng.) -- Memorial University of Newfoundland. / Bibliography : leaf 48. Also available online.

The purpose of this thesis is to advance research in the development of trimaran hullforms and analyze the feasibility of the hullform for a possible naval surface combatant using current hullform design tools. The “Generalized” Trimaran Methodology is a new process that focuses on the manipulation of the three hulled system’s total sectional area curve. The methodology is intended for rapid hull form development during the conceptual design phase, and can analyze an infinite number of trimaran hullforms. The thesis first proposes a new methodology for the design of trimaran hullforms, describes how the process was applied to an existing hullform, presents results of the analysis, and provides validation data from a tow tank resistance experiment.

Thesis (M.S.)--University of West Florida, 2007. / Title from title page of source document. Document formatted into pages; contains 69 pages. Includes bibliographical references.

Thesis (M.Eng.)--Memorial University of Newfoundland, 2000. / Bibliography: leaves [194-197].

With most of the world's untouched oil and gas resources offshore and the possibility that hurricanes are becoming more frequent and more intense, the risks associated with offshore oil and gas production are increasing. Therefore, there is an urgent need to improve current understanding of extreme ocean waves and their interaction with structures. This thesis is concerned with the modelling of extreme ocean waves and their diffraction by offshore structures, with the ultimate aim of proposing improved tools for guiding airgap design. The feasibility of using linear and second order diffraction solutions with a suitable incident wave field to predict extreme green water levels beneath multi-column structures is investigated. Such tools, when fully validated, could replace the need to carry out model tests during preliminary design. When contemplating airgap design it is crucially important that consideration is given to the largest waves in a sea state, the so-called freak or rogue waves. This thesis studies the nature of one specific freak wave for which field data is available, namely the Draupner New Year wave. Unique features of this wave are identified, distinguishing it from a typical large wave, and an estimate of the probability of occurrence of the wave is given. Furthermore, a design wave, called NewWave, is proposed as a good model for large ocean waves and is validated against field and experimental data. The diffraction of regular waves and NewWaves by a number of structural configurations is studied. In order to assess the validity of using diffraction solutions for the purposes of airgap design, comparisons are made with measured wave data from a programme of wave tank experiments. Wave data for a real platform configuration are examined to highlight the key issues complicating the validation of diffraction based design tools for real structures. The ability of diffraction theory to reproduce real wave measurements is discussed. The phenomenon of near-trapping is also investigated, allowing guidelines for airgap design to be established.