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HMS Audacious (1869)
HMS ''Audacious'' was the lead ship of the s built for the Royal Navy in the late 1860s. They were designed as second-class ironclads suitable for use on foreign stations and the ship spent the bulk of her career on the China Station. She was decommissioned in 1894 and hulked in 1902 for use as a training ship. The ship was towed to Scapa Flow after the beginning of the First World War to be used as a receiving ship and then to Rosyth after the war ended. ''Audacious'' was sold for scrap in 1929. Design and description The ''Audacious''-class ironclads were laid out as central battery ironclads with the armament concentrated amidships. They were the first British ironclads to have a two-deck battery with the upper deck guns sponsoned out over the sides of the hull. The ships were fitted with a short, plough-shaped ram and their crew numbered 450 officers and men. HMS ''Audacious'' was long between perpendiculars. She had a beam of and a draught of .Ballard, p. 241 The sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Napier (engineer)
Robert Napier (21 June 1791 – 23 June 1876) was a Scottish marine engineer known for his contributions to Clyde shipbuilding. Early life Robert Napier was born in Dumbarton at the height of the Industrial Revolution, to James and Jean Napier. James was of a line of esteemed bell-wrights, blacksmiths, and engineers, with a brother (also named Robert) who served as blacksmith for the Duke of Argyll at Inveraray Castle. Napier was educated at the burgh school where he took an interest in drawing, which reflected in his later life in an interest in painting and fine arts. Against his father's hopes that he would become a minister in the Church of Scotland, he developed an interest in the family business. At age sixteen, he was confronted by a Royal Navy press gang who intended to conscript him into service during the Napoleonic Wars. Instead of allowing his son to be conscripted, James Napier signed a contract of formal indenture with his son, making him immune to conscripti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boiler (steam Generator)
A boiler is a closed vessel in which fluid (generally water) is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications, including water heating, central heating, boiler-based power generation, cooking, and sanitation. Heat sources In a fossil fuel power plant using a steam cycle for power generation, the primary heat source will be combustion of coal, oil, or natural gas. In some cases byproduct fuel such as the carbon monoxide rich offgasses of a coke battery can be burned to heat a boiler; biofuels such as bagasse, where economically available, can also be used. In a nuclear power plant, boilers called steam generators are heated by the heat produced by nuclear fission. Where a large volume of hot gas is available from some process, a heat recovery steam generator or recovery boiler can use the heat to produce steam, with little or no extra fuel consumed; such a configuration is c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drag (physics)
In fluid dynamics, drag, sometimes referred to as fluid resistance, is a force acting opposite to the direction of motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers, two solid surfaces, or between a fluid and a solid surface. Drag forces tend to decrease fluid velocity relative to the solid object in the fluid's path. Unlike other resistive forces, drag force depends on velocity. Drag force is proportional to the relative velocity for low-speed flow and is proportional to the velocity squared for high-speed flow. This distinction between low and high-speed flow is measured by the Reynolds number. Drag is instantaneously related to vorticity dynamics through the Josephson-Anderson relation. Examples Examples of drag include: * Net force, Net Aerodynamic force, aerodynamic or Fluid dynamics, hydrodynamic force: Drag acting opposite to the direction of movement of a solid object such as cars, aircraft, and boat hulls. * Viscou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biofouling
Biofouling or biological fouling is the accumulation of microorganisms, plants, algae, or small animals where it is not wanted on surfaces such as ship and submarine hulls, devices such as water inlets, pipework, grates, ponds, and rivers that cause degradation to the primary purpose of that item. Such accumulation is referred to as '' epibiosis'' when the host surface is another organism and the relationship is not parasitic. Since biofouling can occur almost anywhere water is present, biofouling poses risks to a wide variety of objects such as boat hulls and equipment, medical devices and membranes, as well as to entire industries, such as paper manufacturing, food processing, underwater construction, and desalination plants. Anti-fouling is the ability of specifically designed materials (such as toxic biocide paints, or non-toxic paints) to remove or prevent biofouling. The buildup of biofouling on marine vessels poses a significant problem. In some instances, the hull str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc
Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table. In some respects, zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity ( electrowinning). Zinc is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It is the second most abundant trace metal in humans after iron, an import ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sister Ship
A sister ship is a ship of the same Ship class, class or of virtually identical design to another ship. Such vessels share a nearly identical hull and superstructure layout, similar size, and roughly comparable features and equipment. They often share a common naming theme, either being named after the same type of thing or person (places, constellations, heads of state) or with some kind of alliteration. Typically the ship class is named for the first ship of that class. Often, sisters become more differentiated during their service as their equipment (in the case of naval vessels, their armament) are separately altered. For instance, the U.S. warships , , , and are all sister ships, each being an . Perhaps the most famous sister ships were the White Star Line's s trio, consisting of , and . As with some other liners, the sisters worked as running mates. Of the three sister ships, ''Titanic'' and ''Britannic'' would both sink within a year of being launched, while RMS ''O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacentric Height
The metacentric height (GM) is a measurement of the initial static stability of a floating body. It is calculated as the distance between the centre of gravity of a ship and its '' metacentre''. A larger metacentric height implies greater initial stability against overturning. The metacentric height also influences the natural period of rolling of a hull, with very large metacentric heights being associated with shorter periods of roll which are uncomfortable for passengers. Hence, a sufficiently, but not excessively, high metacentric height is considered ideal for passenger ships. Different centres The ''centre of buoyancy'' is at the centre of mass of the volume of water that the hull displaces. This point is referred to as B in naval architecture. The '' centre of gravity'' of the ship is commonly denoted as point G or CG. When a ship is at equilibrium, the centre of buoyancy is vertically in line with the centre of gravity of the ship. The metacentre is the point where th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sailing Ballast
Ballast is weight placed low in ships to lower their centre of gravity, which increases stability (more technically, to provide a righting moment to resist any heeling moment on the hull). Insufficiently ballasted boats tend to tip or heel excessively in high winds. Too much heel may result in the vessel filling with water and/or capsizing. If a sailing vessel needs to voyage without cargo, then ballast of little or no value will be loaded to keep the vessel upright. Some or all of this ballast will then be discarded when the cargo is loaded. If a cargo vessel (such as a tanker, bulk carrier or container ship) wishes to travel empty or partially empty to collect cargo, it must travel "in ballast". This keeps the vessel in trim and keeps the propeller and rudder submerged. Typically, being "in ballast" will mean flooding ballast tanks with sea water. Serious problems may arise when ballast water is discharged, as water-borne organisms can create havoc when deposited in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Draft (hull)
The draft or draught of a ship is a determined depth of the vessel below the waterline, measured vertically to its hull's lowest—its propellers, or keel, or other reference point. Draft varies according to the loaded condition of the ship. A deeper draft means the ship will have greater vertical depth below the waterline. Draft is used in under keel clearance calculations, where the draft is calculated with the available depth of water (from Electronic navigational charts) to ensure the ship can navigate safely, without grounding. Navigators can determine their draught by calculation or by visual observation (of the ship's painted load lines). Related terminology A ship's draft/draught is the "depth of the vessel below the waterline measured vertically to the lowest part of the hull, propellers, or other reference point". That is, the draft or draught is the maximum depth of any part of the vessel, including appendages such as rudders, propellers and drop keels if de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beam (nautical)
The beam of a ship is its width at its widest point. The maximum beam (BMAX) is the distance between planes passing through the outer sides of the ship, beam of the hull (BH) only includes permanently fixed parts of the hull, and beam at waterline (BWL) is the maximum width where the hull intersects the surface of the water. Generally speaking, the wider the beam of a ship (or boat), the more initial stability it has, at the expense of secondary stability in the event of a capsize, where more energy is required to right the vessel from its inverted position. A ship that heels on her ''beam ends'' has her deck beams nearly vertical. Typical values Typical length-to-beam ratios ( aspect ratios) for small sailboats are from 2:1 (dinghies to trailerable sailboats around ) to 5:1 (racing sailboats over ). Large ships have widely varying beam ratios, some as large as 20:1. Rowing shells designed for flatwater racing may have length to beam ratios as high as 30:1, while a cora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Length Between Perpendiculars
Length between perpendiculars (often abbreviated as p/p, p.p., pp, LPP, LBP or Length BPP) is the length of a ship along the summer load line from the forward surface of the stem, or main bow perpendicular member, to the after surface of the sternpost, or main stern perpendicular member. When there is no sternpost, the centerline axis of the rudder stock is used as the aft end of the length between perpendiculars. Measuring to the stern post or rudder stock was believed to give a reasonable idea of the ship’s carrying capacity, as it excluded the small, often unusable volume contained in its overhanging ends. On some types of vessels this is, for all practical purposes, a waterline measurement. In a ship with raked stems, naturally that length changes as the draught of the ship changes, therefore it is measured from a defined loaded condition. See also * Length overall Length overall (LOA, o/a, o.a. or oa) is the maximum length of a vessel's hull measured parallel to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
