In the last half-century, high-speed water transportation has developed rapidly. Novel high-performance marine vehicles, such as the air cushion vehicle (ACV), surface effect ship (SES), high-speed monohull craft (MHC), catamaran (CAT), hydrofoil craft (HYC), wave-piercing craft (WPC) and small water area twin hull craft (SWATH) have all developed as concepts, achieving varying degrees of commercial and military success. Prototype ACV and SES have achieved speeds of 100 knots in at calm con- tions; however, the normal cruising speed for commercial operations has remained around 35–50 knots. This is partly due to increased drag in an average coastal s- way where such craft operate services and partly due to limitations of the propulsion systems for such craft. Water jets and water propellers face limitations due to c- itation at high speed, for example. SWATH are designed for reduced motions in a seaway, but the hull form is not a low drag form suitable for high-speed operation. So that seems to lead to a problem – maintain water contact and either water propulsion systems run out of power or craft motions and speed loss are a problem in higher seastates. The only way to higher speed would appear to be to disconnect completely from the water surface. You, the reader, might respond with a question about racing hydroplanes, which manage speeds of above 200 kph. Yes, true, but the power-to-weight ratio is extremely high on such racing machines and not economic if translated into a useful commercial vessel.
Air Lubrication and Air Cavity Technology is a major development that has emerged in recent years as a means to reduce resistance and powering for many types of ships, and an efficient design for high speed marine vessels. This book introduces the mechanisms for boundary layer drag reduction and concepts studied in early research work. Air bubble and sheet lubrication for displacement vessels is outlined and the key projects introduced. Generation of low volume flow air cavities under the hull of displacement, semi displacement and planing vessels are introduced together with theoretical and empirical analysis and design methods. Resistance reduction, power reduction and fuel efficiency are covered for both displacement and high speed vessels. Air layer and air cavity effects on vessel static and dynamic stability are covered, linked to regulatory requirements such as IMO. Seaway motions and reduced impact load of high speed craft in waves are discussed including model test results. Integration of propulsion systems for optimum powering is summarized. A design proposal for a wave piercing air cavity craft is included in an appendix. A comprehensive listing of document resources and internet locations is provided for further research.
High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs.
High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs.
In the last half-century, high-speed water transportation has developed rapidly. Novel high-performance marine vehicles, such as the air cushion vehicle (ACV), surface effect ship (SES), high-speed monohull craft (MHC), catamaran (CAT), hydrofoil craft (HYC), wave-piercing craft (WPC) and small water area twin hull craft (SWATH) have all developed as concepts, achieving varying degrees of commercial and military success. Prototype ACV and SES have achieved speeds of 100 knots in at calm con- tions; however, the normal cruising speed for commercial operations has remained around 35–50 knots. This is partly due to increased drag in an average coastal s- way where such craft operate services and partly due to limitations of the propulsion systems for such craft. Water jets and water propellers face limitations due to c- itation at high speed, for example. SWATH are designed for reduced motions in a seaway, but the hull form is not a low drag form suitable for high-speed operation. So that seems to lead to a problem – maintain water contact and either water propulsion systems run out of power or craft motions and speed loss are a problem in higher seastates. The only way to higher speed would appear to be to disconnect completely from the water surface. You, the reader, might respond with a question about racing hydroplanes, which manage speeds of above 200 kph. Yes, true, but the power-to-weight ratio is extremely high on such racing machines and not economic if translated into a useful commercial vessel.
This definitive text describes the theory and design both of Air Cushion Vehicles (ACV) and Surface Effect Ships (SES). It begins by introducing hovercraft types and their development and application throughout the world in the last three decades, before going on to discuss the theoretical aspects of ACV and SES craft covering their hovering performance, dynamic trim over calm water, resistance, stability, manoeuvrability, skirt configuration and analysis of forces acting on the skirts, ACV and SES seakeeping, and the methodology of scaling aerodynamic and hydrodynamic forces acting on the ACV/SES from model test data. The latter chapters describe a design methodology, including design criteria and standard methods for estimating craft performance, lift system design, skirt design, hull structure, propulsion systems and power unit selection. Much technical information, data, and references to further work on hovercraft and SES design is provided. The book will be a useful reference to engineers, technicians, teachers, students (both undergraduate and postgraduate), operators etc. who are involved in ACV/SES research, design, construction and operation. - Guides the reader on how to perform machinery and systems selection within ACV and SES overall design - For teachers, students (both at under- and post-graduate level), engineers and technicians involved in ACV/SES
Air Lubrication and Air Cavity Technology is a major development that has emerged in recent years as a means to reduce resistance and powering for many types of ships, and an efficient design for high speed marine vessels. This book introduces the mechanisms for boundary layer drag reduction and concepts studied in early research work. Air bubble and sheet lubrication for displacement vessels is outlined and the key projects introduced. Generation of low volume flow air cavities under the hull of displacement, semi displacement and planing vessels are introduced together with theoretical and empirical analysis and design methods. Resistance reduction, power reduction and fuel efficiency are covered for both displacement and high speed vessels. Air layer and air cavity effects on vessel static and dynamic stability are covered, linked to regulatory requirements such as IMO. Seaway motions and reduced impact load of high speed craft in waves are discussed including model test results. Integration of propulsion systems for optimum powering is summarized. A design proposal for a wave piercing air cavity craft is included in an appendix. A comprehensive listing of document resources and internet locations is provided for further research.
High speed catamaran and multihull high speed marine vessel have become very popular in the last two decades. The catamaran has become the vessel of choice for the majority of high speed ferry operators worldwide. There have been significant advances in structural materials, and structural design has been combined with higher power density and fuel efficient engines to deliver ferries of increasing size. The multihull has proven itself to be a suitable configuration for active power projection across oceans as well as for coastal patrol and protection, operating at high speedd for insertion or retrieval with a low energy capability. At present there is no easily accessible material covering the combination of hydrodynamics, aerodynamics, and design issues including structures, powering and propulsion for these vehicles. Coverage in High Speed Catamarans and Multihulls includes an introduction to the history, evolution, and development of catamarans, followed by a theoretical calculation of wave resistance in shallow and deep water, as well as the drag components of the multihull. A discussion of vessel concept design describing design characteristics, empirical regression for determination of principal dimensions in preliminary design, general arrangement, and methods is also included. The book concludes with a discussion of experimental future vehicles currently in development including the small waterplane twin hull vessels, wave piercing catamarans, planing catamarans, tunnel planing catamarans and other multihull vessels.
National Bestseller One of Newfoundland's funniest and most beloved storytellers offers his cure for the Covid blues. Is there a more sociable province than Newfoundland and Labrador? Or anywhere in Canada with a greater reputation for coming to the rescue of those in need? At this time of Covid, singer, songwriter and bestselling author Alan Doyle is feeling everyone's pain. Off the road and spending more days at home than he has since he was a child hawking cod tongues on the wharfs of Petty Harbour, he misses the crowds and companionship of performing across the country and beyond. But most of all he misses the cheery clamour of pubs in his hometown, where one yarn follows another so quickly "you have to be as ready as an Olympian at the start line to get your tale in before someone is well into theirs already." We're all experiencing our own version of that deprivation, and Alan, one of Newfoundland's finest storytellers, wants to offer a little balm. All Together Now is a gathering in book form--a virtual Newfoundland pub. There are adventures in foreign lands, including an apparently filthy singalong in Polish (well, he would have sung along if he'd understood the language), a real-life ghost story involving an elderly neighbour, a red convertible and a clown horn, a potted history of his social drinking, and heartwarming reminiscences from another past world, childhood--all designed to put a smile on the faces of the isolated-addled. Alan Doyle has never been in better form--nor more welcome. As he says about this troubling time: "We get through it. We do what has to be done. Then, we celebrate. With the best of them.
Alan Lomax (1915-2002) began working for the Archive of American Folk Song at the Library of Congress in 1936, first as a special and temporary assistant, then as the permanent Assistant in Charge, starting in June 1937, until he left in late 1942. He recorded such important musicians as Woody Guthrie, Muddy Waters, Aunt Molly Jackson, and Jelly Roll Morton. A reading and examination of his letters from 1935 to 1945 reveal someone who led an extremely complex, fascinating, and creative life, mostly as a public employee. While Lomax is noted for his field recordings, these collected letters, many signed "Alan Lomax, Assistant in Charge," are a trove of information until now available only at the Library of Congress. They make it clear that Lomax was very interested in the commercial hillbilly, race, and even popular recordings of the 1920s and after. These letters serve as a way of understanding Lomax's public and private life during some of his most productive and significant years. Lomax was one of the most stimulating and influential cultural workers of the twentieth century. Here he speaks for himself through his voluminous correspondence.
In the last decade of his life, Leacock turned to writing informal essays that blended humour with a conversational style and ripened wisdom to address the issues he cared about most - education, literature, economics, Canada and its place in the world - and to confront the joys and sorrows of his own life. With an introduction that sets them in the context of his life, thoughts and times, these essays reveal a passionate, intellegent, personal Leacock, against a backdrop of Depression and war, finding hope and conveying the timeless message that only the human spirit can bring social justice, peace, and progress.
This will help us customize your experience to showcase the most relevant content to your age group
Please select from below
Login
Not registered?
Sign up
Already registered?
Success – Your message will goes here
We'd love to hear from you!
Thank you for visiting our website. Would you like to provide feedback on how we could improve your experience?
This site does not use any third party cookies with one exception — it uses cookies from Google to deliver its services and to analyze traffic.Learn More.