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Exhaust Pulse Pressure Charging
Exhaust pulse pressure charging (EPPC) is a system for supercharging two-stroke diesel engines of the loop-scavenge type. Loop-scavenge engines cannot be pressure-charged in the same way as uniflow engines or four-stroke engines because the inlet and exhaust ports are open at the same time. Overview The engine usually has a Roots blower to provide air for scavenging and this is arranged to deliver excess air so that air follows the exhaust gases into the exhaust manifold. Some of this air is then forced back into the cylinder by a rise in pressure in the exhaust manifold resulting from the exhaust pulse from another cylinder. For additional pressure charging a turbocharger may be fitted, in series with the Roots blower, but a turbocharger cannot be used alone because it would not provide enough air for scavenging at low speeds. Exhaust Pulse Pressure Charging Advantages and Disadvantages Pulse pressure charging is much more effective with a low load and at low speed than tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supercharger
In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induction that is mechanically powered (usually by a belt from the engine's crankshaft), as opposed to a turbocharger, which is powered by the kinetic energy of the exhaust gasses. However, up until the mid-20th century, a turbocharger was called a "turbosupercharger" and was considered a type of supercharger. The first supercharged engine was built in 1878, with usage in aircraft engines beginning in the 1910s and usage in car engines beginning in the 1920s. In piston engines used by aircraft, supercharging was often used to compensate for the lower air density at high altitudes. Supercharging is less commonly used in the 21st century, as manufacturers have shifted to turbochargers to reduce fuel consumption and/or increase power outputs. Des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WAGR X Class
The X Class were a class of diesel locomotive built by Beyer, Peacock & Company and Metropolitan-Vickers, Bowesfield Works, Stockton-on-Tees for the Western Australian Government Railways between 1954 and 1956. Construction In the early 1950s the Western Australian Government Railways placed the largest single Australian order for diesel locomotives, when it ordered 48 2-Do-2 locomotives from Beyer, Peacock and Company and Metropolitan-Vickers. All were delivered between 1954 and 1956. The seeds for the construction of the class were laid in by the then WAGR Chief Mechanical Engineer, Tom Marsland, with a proposal for the acquisition of 87 diesel locomotives, including 3 small jetty shunters, 18 diesel shunters and 66 mainline locomotives, later reduced to 48 when railcars were selected for suburban service. The proposal developed further during discussions with Beyer, Peacock regarding issues with the design of the W Class locomotive. Operation The X class revolutionised ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superchargers
In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induction that is mechanically powered (usually by a belt from the engine's crankshaft), as opposed to a turbocharger, which is powered by the kinetic energy of the exhaust gasses. However, up until the mid-20th century, a turbocharger was called a "turbosupercharger" and was considered a type of supercharger. The first supercharged engine was built in 1878, with usage in aircraft engines beginning in the 1910s and usage in car engines beginning in the 1920s. In piston engines used by aircraft, supercharging was often used to compensate for the lower air density at high altitudes. Supercharging is less commonly used in the 21st century, as manufacturers have shifted to turbochargers to reduce fuel consumption and/or increase power outputs. Des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure Wave Supercharger
A pressure wave supercharger (also known as a wave rotor) is a type of supercharger technology that harnesses the pressure waves produced by an internal combustion engine exhaust gas pulses to compress the intake air. Its automotive use is not widespread; the most widely used example is the ''Comprex'', developed by Brown Boveri.A Review of Wave Rotor Technology and its Applications including details of Comprex supercharger Valmet Tractors of Finland were one of the first to use the device when they fitted it to the 411CX engine which powered their 1203 model of 1980. Although it provided a useful increase in performance it was considered too expensive to be incorporated into later models. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kadenacy Effect
The Kadenacy effect is an effect of pressure-waves in gases. It is named after Michel Kadenacy who obtained a French patent for an engine utilizing the effect in 1933. There are also European and US patents. In simple terms, the momentum of the exhaust gas leaving the cylinder of an internal combustion engine creates a pressure-drop in the cylinder which assists the flow of a fresh charge of air, or fuel-air mixture, into the cylinder. The effect can be maximized by careful design of the inlet and exhaust passages. Uses The Kadenacy effect has been utilized in pulse jet engines and in two-stroke piston engines and is important in the design of high-performance motorcycle engines. Pulse jets Two-stroke engines In a two-stroke engine the pressure-drop resulting from the Kadenacy effect assists the flow of a fresh fuel-air mixture charge into the cylinder. However, the Kadenacy effect alone is not sufficient and must be boosted in some way. In small engines this is done by cra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inertial Supercharging Effect
The inertial supercharging effect is the increase of volumetric efficiency in the cylinder of an engine. Background The internal combustion engine is the most common engine found in mechanical devices across the world. The engine is powered by an air/gasoline mixture and the physics principles of heat and pressure. Overview Inertial supercharging effect is the result of incoming fuel/air charge developing momentum greater than intake stroke would generate alone. It is achieved by the careful design of the shape of the piston head, the valves and cam profile/valve timing which creates a vacuum that pulls more exhaust gases (and some of the intake gasses) out of the engine. This is immediately followed by a reflected pressure wave timed to force the extra intake gasses back into the cylinder, thus achieving a greater mass of air/fuel mix in the combustion chamber than possible with conventional methods. Expansion chambers only work well at a narrow engine speed range which is wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Backpressure
Back pressure (or backpressure) is a resistance or force opposing the desired flow of fluid through pipes, leading to friction loss and pressure drop. The term ''back pressure'' is a misnomer, as pressure is a scalar quantity, so it has a magnitude but no direction. The fluid is what is directed, tending to flow away from high-pressure regions and toward low-pressure regions. If the low-pressure space is more high-pressure than intended (e.g. due to obstructions or tight bends in an exhaust pipe) or the high-pressure space is more low-pressure than intended, this opposes the desired flow and reduces the discharge. Similarly, bending or other operations on a pipe (such as a stock car exhaust system with a particularly high number of twists and bends) can reduce flow rate. Explanation A common example of backpressure is that caused by the exhaust system (consisting of the exhaust manifold, catalytic converter, muffler and connecting pipes) of an automotive four-stroke engine, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Rail Class D3/3
British Rail Class D3/3 was a 0-6-0 shunting locomotive built by British Rail at their Derby Works in England. It was similar to the British Rail Class 08, except they were built with different engines and traction motors. They were all withdrawn and scrapped after only twelve years of service. See also * List of British Rail classes This article lists the wide variety of locomotives and multiple units that have operated on Great Britain's railway network, since Nationalisation in 1948. British Rail used several numbering schemes for classifying its steam locomotive types ... Sources * Ian Allan ABC of British Railways Locomotives, Winter 1962/3 * D003.03 C locomotives Railway locomotives introduced in 1955 Scrapped locomotives Standard gauge locomotives of Great Britain Diesel-electric locomotives of Great Britain {{diesel-loco-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CIE 201 Class
The Córas Iompair Éireann 201 Class was a class of 34 diesel electric locomotives manufactured by Metropolitan-Vickers at their Dukinfield Works in Manchester. They were a smaller, lighter and less powerful version of the 001 Class and were originally intended for branch line passenger and freight (mixed traffic) duties. They were introduced in 1956 and, although their duties changed over the years, were in regular service on the Irish railway network until the mid-1980s. Six were sold to Northern Ireland Railways (NIR) in 1986. Service history Unfortunately, these locomotives suffered from two distinct problems: * During the late 1950s and early 1960s, following the publication of the Andrews Report (mimicking the widescale the Beeching Axe in Britain), CIÉ undertook large-scale closures of branch lines, leaving the engines without a purpose. *The locomotives were of insufficient power for their duties and their Crossley engines suffered reliability problems. The exist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CIE 001 Class
The Córas Iompair Éireann 001 Class locomotive was manufactured by Metropolitan-Vickers at their Dukinfield Works in Manchester. The 001 Class locomotive was the backbone of mainline passenger and freight train services on the Irish railway network for forty years from 1955 until the mid-1990s when they were replaced by the new 201 Class. Engines Crossley Initially they were fitted with eight-cylinder two-stroke, port-controlled Crossley engines. These were a loop scavenge type, which utilised a patented principle that recycled the normally wasted exhaust-pressure pulse to boost charge air in the cylinder. They produced at 625 rpm and could do . The original sandboxes, which were used to improve traction with the rail, were removed after a few years. Their Crossley engines proved to be notoriously unreliable from the start. Amongst a plethora of problems were: * Unbalanced engines resulting in vibration-induced fuel pipe and water pipe fractures * Cylinder defects * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-stroke Cycle
A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a power cycle with two strokes (up and down movements) of the piston during one power cycle, this power cycle being completed in one revolution of the crankshaft. A four-stroke engine requires four strokes of the piston to complete a power cycle during two crankshaft revolutions. In a two-stroke engine, the end of the combustion stroke and the beginning of the compression stroke happen simultaneously, with the intake and exhaust (or scavenging) functions occurring at the same time. Two-stroke engines often have a high power-to-weight ratio, power being available in a narrow range of rotational speeds called the power band. Two-stroke engines have fewer moving parts than four-stroke engines. History The first commercial two-stroke engine involving cylinder compression is attributed to Scottish engineer Dugald Clerk, who patented his design in 1881. However, unlike most later two-st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Rail Class 28
The British Rail Class 28 ( Metro-Vick Type 2) diesel-electric locomotives, known variously as 'Metrovicks', 'Crossleys' or 'Co-Bos', were built under the Pilot Scheme for diesel locomotives as part of the British Railways 1955 Modernisation Plan. These Crossley-engined locomotives were one of two designs built under the Pilot Scheme to use two-stroke diesel engines, the other being the Class 23 'Baby Deltic' locomotives. The locomotives had a Co-Bo wheel arrangement (a 6-wheel bogie at one end, a 4-wheel bogie at the other) – unique in British Railways practice and uncommon in other countries, although Japan also used some C-B diesel hydraulics. The maximum tractive effort of was unusually high for a Type 2 locomotive but, as there were five (not four) driving axles, the risk of wheelslip was minimal. Origin Work had begun on the Pilot Scheme in 1954 and the first plan for 174 locomotives (all classes) had been produced by October 1954, including 20 of these Metro-Vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
