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Uniflow Steam Engine
The uniflow type of steam engine uses steam that flows in one direction only in each half of the cylinder. Thermal efficiency is increased by having a temperature gradient along the cylinder. Steam always enters at the hot ends of the cylinder and exhausts through ports at the cooler centre. By this means, the relative heating and cooling of the cylinder walls is reduced. Design details Steam entry is usually controlled by poppet valves (which act similarly to those used in internal combustion engines) that are operated by a camshaft. The inlet valves open to admit steam when minimum expansion volume has been reached at the start of the stroke. For a period of the crank cycle, steam is admitted, and the poppet inlet is then closed, allowing continued expansion of the steam during the stroke, driving the piston. Near the end of the stroke, the piston will uncover a ring of exhaust ports mounted radially around the centre of the cylinder. These ports are connected by a manifold a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tom Varley
Tom Varley was a collector, restorer and preserver of steam-powered road vehicles, known for the Tom Varley Collection, a steam museum mostly of steam wagons, ''"a lasting legacy of which [British steam road enthusiasts] can be proud"''. His business was in running Todber Caravan Park at Gisburn, in the high Pennines of Lancashire. The steam museum was housed in a barn alongside the caravans. The collection was best known from its frequent appearances at steam rally, steam rallies through the 1970s and '80s. Varley's wagons were recognisable from their fine paintwork and signwriting, each named and prefixed ''Pendle ...''. Six of his rarer, and often unique survivors, were re-imported from Australia before restoration. Tom Varley died December 12, 1990. His contribution to the preservation of steam vehicles in the UK has been widely recognised. List of vehicles : These vehicles have at one point formed part of the Tom Varley collection. Since his death, some have now been so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piston Engines
A reciprocating engine, more often known as a piston engine, is a heat engine that uses one or more reciprocating pistons to convert high temperature and high pressure into a rotating motion. This article describes the common features of all types. The main types are: the internal combustion engine, used extensively in motor vehicles; the steam engine, the mainstay of the Industrial Revolution; and the Stirling engine for niche applications. Internal combustion engines are further classified in two ways: either a spark-ignition (SI) engine, where the spark plug initiates the combustion; or a compression-ignition (CI) engine, where the air within the cylinder is compressed, thus heating it, so that the heated air ignites fuel that is injected then or earlier.''Thermodynamics: An Engineering Approach'' by Yunus A. Cengal and Michael A. Boles Common features in all types There may be one or more pistons. Each piston is inside a cylinder, into which a gas is introduced, eit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steam Engines
A steam engine is a heat engine that performs Work (physics), mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a Cylinder (locomotive), cylinder. This pushing force can be transformed by a connecting rod and Crank (mechanism), crank into rotational force for work. The term "steam engine" is most commonly applied to reciprocating engines as just described, although some authorities have also referred to the steam turbine and devices such as Hero's aeolipile as "steam engines". The essential feature of steam engines is that they are external combustion engines, where the working fluid is separated from the combustion products. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle. In general usage, the term ''steam engine'' can refer to either complete steam plants (including Boiler (power generation), boilers etc.), such as railway steam locomot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Steam Technology
Advanced steam technology (sometimes known as modern steam) reflects an approach to the technical development of the steam engine intended for a wider variety of applications than has recently been the case. Particular attention has been given to endemic problems that led to the demise of steam power in small to medium-scale commercial applications: excessive pollution, maintenance costs, labour-intensive operation, low power/weight ratio, and low overall thermal efficiency. Steam power has generally been superseded by the internal combustion engine or by electrical power drawn from an electrical grid. The only steam installations that are in widespread use are the highly efficient thermal power plants used for generating electricity on a large scale. In contrast, the proposed steam engines may be for stationary, road, rail, or marine use. Improving steam traction Although most references to "Modern Steam" apply to developments since the 1970s, certain aspects of advanced s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bash Valve
A bash valve is a valve within a piston engine, used to control the admission of the working fluid.Bash Valve - description They are directly actuated valves, operated by contact between the piston and the valve tip. Bash valves have the advantage of great simplicity, for manufacture and operation. Their disadvantages are that their opening and closing times are relatively crudely controlled, compared to other types of . The valve is usually constructed as a circular with a conical seat, inserted into the cylinder from the outside. A protrusion on the inside is h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-stroke
A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a power cycle with two strokes of the piston, one up and one down, in one revolution of the crankshaft in contrast to a four-stroke engine which requires four strokes of the piston in two crankshaft revolutions to complete a power cycle. During the stroke from bottom dead center to top dead center, the end of the exhaust/intake (or scavenging) is completed along with the compression of the mixture. The second stroke encompasses the combustion of the mixture, the expansion of the burnt mixture and, near bottom dead center, the beginning of the scavenging flows. Two-stroke engines often have a higher power-to-weight ratio than a four-stroke engine, since their power stroke occurs twice as often. Two-stroke engines can also have fewer moving parts, and thus be cheaper to manufacture and weigh less. In countries and regions with stringent emissions regulation, two-stroke engines have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bash Valve
A bash valve is a valve within a piston engine, used to control the admission of the working fluid.Bash Valve - description They are directly actuated valves, operated by contact between the piston and the valve tip. Bash valves have the advantage of great simplicity, for manufacture and operation. Their disadvantages are that their opening and closing times are relatively crudely controlled, compared to other types of . The valve is usually constructed as a circular with a conical seat, inserted into the cylinder from the outside. A protrusion on the inside is h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White Cliffs Solar Power Station
White Cliffs Solar Power Station was Australia's first solar power station. It is located at White Cliffs, New South Wales, which was chosen as it has the highest insolation in New South Wales, and in 1981 when the station was constructed had no grid connection. Constructed by a team from Australian National University, the station consisted of fourteen five-metre parabolic dishes, each covered with more than 2000 mirrors and mounted on a heliostatic mounting. The dishes each focussed the sun's rays on a collector, where water was boiled. The resulting steam drove a three-cylinder Uniflow steam engine, made by modifying a Lister diesel engine, delivering up to 25kWe. Batteries were used to provide 24-hour power to selected buildings in the township, and an existing diesel generator retained to provide battery charging when either low insolation or strong winds prevented use of the solar station for extended periods. In 1996, following grid connection of the township, the stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and hangar facilities for supporting, arming, deploying and recovering carrier-based aircraft, shipborne aircraft. Typically it is the capital ship of a naval fleet, fleet (known as a carrier battle group), as it allows a naval force to power projection, project seaborne naval aviation, air power far from homeland without depending on local airfields for staging area, staging aerial warfare, aircraft operations. Since their inception in the early 20th century, aircraft carriers have evolved from wooden vessels used to deploy individual tethered reconnaissance balloons, to nuclear marine propulsion, nuclear-powered supercarriers that carry dozens of fighter aircraft, fighters, strike aircraft, military helicopters, airborne early warning and control, AEW&Cs and other types of aircraft such as unmanned combat aerial vehicle, UCAVs. While heavier fixed-wing aircraft such as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Lakes
The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes spanning the Canada–United States border. The five lakes are Lake Superior, Superior, Lake Michigan, Michigan, Lake Huron, Huron, Lake Erie, Erie, and Lake Ontario, Ontario (though hydrologically, Lake Michigan–Huron, Michigan and Huron are a single body of water, joined at the Straits of Mackinac). The Great Lakes Waterway enables modern travel and shipping by water among the lakes. The lakes connect to the Atlantic Ocean via the Saint Lawrence River, and to the Mississippi River basin through the Illinois Waterway. The Great Lakes are the largest group of freshwater lakes on Earth by total area and the second-largest by total volume. They contain 21% of the world's surface fresh water by volume. The total surface is , and the total volume (measured at the low water datum) is , slightly less than the volume of Lake Baikal (, 22–23% of the world's surface f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Train Ferry
A train ferry is a ship (ferry) designed to carry Railroad car, railway vehicles, as well as their cargoes and passengers. Typically, one level of the ship is fitted with Track (rail transport), railway tracks, and the vessel has a door at the front and/or rear to give access to the wharves. In the United States, train ferries are sometimes referred to as "car ferries", as distinguished from "auto ferries" used to transport automobiles. The wharf (sometimes called a "ferry slip, slip") has a ramp, and a Linkspan#Train ferry, linkspan or "apron", balanced by weights, that connects the railway proper to the ship, allowing for tidal or seasonal changes in water level. While railway vehicles can be and are shipped on the decks or in the holds of ordinary ships, purpose-built train ferries can be quickly loaded and unloaded by roll-on/roll-off, especially as several vehicles can be loaded or unloaded at once. A train ferry that is a barge is called a car float or rail barge. Some trai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
