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Marine Engines
Marine propulsion is the mechanism or system used to generate thrust to move a watercraft through water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting of an electric motor or internal combustion engine driving a propeller, or less frequently, in pump-jets, an impeller. Marine engineering is the discipline concerned with the engineering design process of marine propulsion systems. Human-powered watercraft, Human-powered paddles and oars, and later, sails were the first forms of marine propulsion. Rowed galleys, some equipped with sail, played an important early role in early human seafaring and naval warfare, warfares. The first advanced mechanical means of marine propulsion was the marine steam engine, introduced in the early 19th century. During the 20th century it was replaced by two-stroke diesel engine, two-stroke or four-stroke diesel engines, outboard motors, and gas turbine engines on faster s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galley
A galley is a type of ship that is propelled mainly by oars. The galley is characterized by its long, slender hull, shallow draft, and low freeboard (clearance between sea and gunwale). Virtually all types of galleys had sails that could be used in favorable winds, but human effort was always the primary method of propulsion. This allowed galleys to navigate independently of winds and currents. The galley originated among the seafaring civilizations around the Mediterranean Sea in the late second millennium BC and remained in use in various forms until the early 19th century in warfare, trade, and piracy. Galleys were the warships used by the early Mediterranean naval powers, including the Greeks, Illyrians, Phoenicians, and Romans. They remained the dominant types of vessels used for war and piracy in the Mediterranean Sea until the last decades of the 16th century. As warships, galleys carried various types of weapons throughout their long existence, including rams, catapults ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
