Summary: Cavitation is the transition of a fluid into vapour due to local reduction of pressure which is generated by high local flow velocities. The transition of a fluid into vapour also occurs during cooking of water by an increase of the local temperature. The term cavitation is generally reserved for conditions in which the temperature of the bulk fluid is not changed. Although cavitation can occur in many situations this course focuses on ship hydrodynamics and ship propellers. The course is divided into five main groups: physics, types and effects of cavitation as well as calculations and test facilities and techniques. Some of these topics are illustrated with the use of videos. (Study goals:) 1. Reproduce the main lines in a selection of the latest developments in the field of propulsion and resistance hydrodynamics, where the current selection of propulsion and resistance topics includes unsteady hydrodynamics of the flow over a foil, cavitation forms, problems and tools for analysis and design, propulsion systems in a service environment and ship drag reduction by air lubrication. 2. Analyse a hydrodynamic problem in the propulsion and resistance area, into well defined sub problems that can be analysed with state of the art knowledge and tools 3. Select the appropriate theory or tool (either numerical or experimental) for an analysis of the identified problem. 4. Reproduce and present to an audience, the main lines in a contemporary publication from the field of Propulsion and Resistance hydrodynamics. 5. Understand, interpret and react to questions from the audience and the lecturer and in doing so, stimulate the scientific debate.
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In dredging, trenching, (deep sea) mining, drilling, tunnel boring and many other applications, sand, clay or rock has to be excavated. This book gives an overview of cutting theories. It starts with a generic model, which is valid for all types of soil (sand, clay and rock) after which the specifics of dry sand, water saturated sand, clay, atmospheric rock and hyperbaric rock are covered. For each soil type small blade angles and large blade angles, resulting in a wedge in front of the blade, are discussed. For each case considered, the equations/model for the cutting forces, power and specific energy are given. The models are verified with laboratory research, mainly at the Delft University of Technology, but also with data from literature.
The course covers the basic techniques for evaluating the maximum forces and loads over the life of a marine structure or vehicle, so as to be able to design its basic configuration. Loads and motions of small and large structures and their short-term and long-term statistics are studied in detail and many applications are presented in class and studied in homework and laboratory sessions. Issues related to seakeeping of ships are studied in detail. The basic equations and issues of maneuvering are introduced at the end of the course. Three laboratory sessions demonstrate the phenomena studied and provide experience with experimental methods and data processing.
Dredging equipment, mechanical dredgers, hydraulic dredgers, boundary conditions, design criteria, instrumentation and automation.
In dredging, production estimating is carried out mainly with analytical physical models of the different dredging processes.
Slurry transport of settling slurries and cutting processes in sand, clay and rock are already covered in two other books by the author.
Other processes like hopper sedimentation and erosion, water jet fluidization, cutter head spillage, pump/pipeline dynamics and clamshell dredging are covered in this Special Topics Edition.
New topics may be added in the near future.
The course focuses on three main dredging processes: the cutting of sand, clay and rock, the sedimentation process in hopper dredges and the breaching process
This is a travel itinerary featuring 13 historic shipwrecks in waters near Florida, a convergence point for maritime trade routes. Learn about the historical significance of these 13 shipwrecks. See photos and an essay on Florida maritime history.
tells the story of two World War II ship-building efforts. In 1941, with war raging in Europe, President Roosevelt authorized the production of 441-foot cargo ships. These Liberty ships proved too slow and small, so in 1943, a new effort began building Victory ships, which cruised at 18.5 mph, compared to the Liberty's 12.5 mph. By the war's end, the Maritime Commission had built 2,751 Liberty and 531 Victory ships.
This course discusses the selection and evaluation of commercial and naval ship power and propulsion systems. It will cover the analysis of propulsors, prime mover thermodynamic cycles, propeller-engine matching, propeller selection, waterjet analysis, and reviews alternative propulsors. The course also investigates thermodynamic analyses of Rankine, Brayton, Diesel, and Combined cycles, reduction gears and integrated electric drive. Battery operated vehicles and fuel cells are also discussed. The term project requires analysis of alternatives in propulsion plant design for given physical, performance, and economic constraints. Graduate students complete different assignments and exams.
This is is a travel itinerary highlighting 89 historic places that tell the story of Massachusetts' relationship with the sea. Read essays about lighthouses and lifesaving stations, ships and shipbuilding, the U.S. Navy, and maritime commerce.
Introduces the concepts and applications of navigation techniques using celestial bodies and satellite positioning systems such as the Global Positioning System (GPS). Topics include astronomical observations, radio navigation systems, the relationship between conventional navigation results and those obtained from GPS, and the effects of the security systems, Selective Availability, and anti-spoofing on GPS results. Laboratory sessions cover the use of sextants, astronomical telescopes, and field use of GPS. Application areas covered include ship, automobile, and aircraft navigation and positioning, including very precise positioning applications.
Appliquer l’algorithme dans la résolution d'un problème spécifique simple • Montrer une attitude positive vis-à-vis de l'utilisation de l’algorithme dans la résolution des problèmes de la vie. • Décrire les composantes d'un algorithme.
The course treats the design of offshore mooring systems literally from the ground up: Starting with the anchor and its soils mechanics in the sea bed, via the mechanics of a single mooring line and system of lines. The course concludes by touching on other mooring concepts and the dynamic behavior of the moored object as a non-linear mechanical system.
This lesson provides a basic introduction to celestial navigation for navigators, sailors, and others interested in the topic. It begins with the relationship between celestial coordinates and Earth coordinates and examines key celestial navigation parameters—geographic position, sextant altitude, observed altitude, azimuth, and computed altitude—that can be used to identify to a ship's position. A U.S. Navy navigator demonstrates the main celestial sights performed over the course of a day, including the morning three-star fix, morning Sun line, Local Apparent Noon Sun line, afternoon Sun line, and evening three-star fix, and demonstrates how the sight reduction culminates in a marked intercept and line of position on a navigation plot. The concepts of fix, running fix, estimated position, dead reckoning, and assumed position are also discussed. Although no formal background is needed for this lesson, some familiarity with the basics of navigation and the Universal Plotting Sheet will be useful to the learner.
This course presents principles of naval architecture, ship geometry, hydrostatics, calculation and drawing of curves of form, intact and damage stability, hull structure strength calculations and ship resistance. It introduces computer-aided naval ship design and analysis tools. Projects include analysis of ship lines drawings, calculation of ship hydrostatic characteristics, analysis of intact and damaged stability, ship model testing, and hull structure strength calculations.
This subject teaches students, having an initial interest in sailing design, how to design good yachts. Topics covered include hydrostatics, transverse stability, and the incorporation of the design spiral into one's working methods. Computer aided design (CAD) is used to design the shapes of hulls, appendages and decks, and is an important part of this course. The capstone project in this course is the Final Design Project in which each student designs a sailing yacht, complete in all major respects. The central material for this subject is the content of the book Principals of Yacht Design by Larssson and Eliasson (see further description in the syllabus). All the class lectures are based on the material in this book. The figures in the book which are shown in class (but not reproduced on this site), contain the essential material and their meaning is explained in detail during the lecture sessions. Mastery of the material in the book and completing a design project provides the desired and needed education.
Ship longitudinal strength and hull primary stresses. Ship structural design concepts. Effect of superstructures and dissimilar materials on primary strength. Transverse shear stresses in the hull girder. Torsional strength of ships.Design limit states including plate bending, column and panel buckling, panel ultimate strength, and plastic analysis. Matrix stiffness, grillage, and finite element analysis. Computer projects on the structural design of a midship module. This course is intended for first year graduate students and advanced undergraduates with an interest in design of ships or offshore structures. It requires a sufficient background in structural mechanics. Computer applications are utilized, with emphasis on the theory underlying the analysis. Hydrostatic loading, shear load and bending moment, and resulting primary hull primary stresses will be developed. Topics will include; ship structural design concepts, effect of superstructures and dissimilar materials on primary strength, transverse shear stresses in the hull girder, and torsional strength among others. Failure mechanisms and design limit states will be developed for plate bending, column and panel buckling, panel ultimate strength, and plastic analysis. Matrix stiffness, grillage, and finite element analysis will be introduced. Design of a ship structure will be analyzed by "hand" with desktop computer tools and a final design project using current applications for structural design of a section will be accomplished.
In dredging, trenching, (deep sea) mining, drilling, tunnel boring and many other applications, sand, clay or rock has to be excavated.The book covers horizontal transport of settling slurries (Newtonian slurries). Non-settling (non-Newtonian) slurries are not covered.
This class is jointly sponsored by the MIT Museum, Massachusetts Bay Maritime Artisans, the Department of Mechanical Engineering's Center for Ocean Engineering, and the Department of Architecture. The course teaches the fundamental steps in traditional boat design and demonstrates connections between craft and modern methods. Instructors provide vessel design orientation and then students carve their own shape ideas in the form of a wooden half-hull model. Experts teach the traditional skills of visualizing and carving your model in this phase of the class. After the models are completed, a practicing naval architect guides students in translating shape from models into a lines plan. The final phase of the class is a comparative analysis of the designs generated by the group.