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46-397: The upgrading consisted of replacement of the piston engine with a 1,025 kW (1,375 shp) TVD-20 turboprop engine, featuring a three-blade reversible pitch (type AV-17) propeller and a R-17 speed governor . The flight compartment was rearranged; a heating and ventilation system was installed as well as advanced electric and flight and navigation equipment; centralized warning system;

92-441: A crankshaft or by a swashplate or other suitable mechanism. A flywheel is often used to ensure smooth rotation or to store energy to carry the engine through an un-powered part of the cycle. The more cylinders a reciprocating engine has, generally, the more vibration-free (smoothly) it can operate. The power of a reciprocating engine is proportional to the volume of the combined pistons' displacement. A seal must be made between

138-459: A flywheel , the power from other pistons connected to the same shaft or (in a double acting cylinder ) by the same process acting on the other side of the piston. This is where the piston forms the smallest volume in the cylinder. In most types the expanded or " exhausted " gases are removed from the cylinder by this stroke . The exception is the Stirling engine , which repeatedly heats and cools

184-577: A piston engine , is typically 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

230-440: 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 . There may be one or more pistons. Each piston is inside a cylinder , into which a gas is introduced, either already under pressure (e.g. steam engine ), or heated inside

276-432: A "Black Box" ignition amplifier, intended to take the load off the distributor's breaker points during high rpm runs, which was used by Dodge and Plymouth on their factory Super Stock Coronet and Belvedere drag racers . This amplifier was installed on the interior side of the cars' firewall, and had a duct which provided outside air to cool the unit. The rest of the system (distributor and spark plugs) remains as for

322-731: A FORD designed breakerless system on the Lotus 25s entered at Indianapolis the next year, ran a fleet test in 1964, and began offering optional EI on some models in 1965. This electronic system was utilized on the GT40s campaigned by Shelby American and Holman and Moody. Robert C. Hogle, Ford Motor Company, presented the, "Mark II-GT Ignition and Electrical System", Publication #670068, at the SAE Congress, Detroit, Michigan, January 9–13, 1967. Beginning in 1958, Earl W. Meyer at Chrysler worked on EI, continuing until 1961 and resulting in use of EI on

368-597: A capacity of 1,820 L (64 cu ft), making a total capacity of 25,480 L (900 cu ft) for the largest versions. For piston engines, an engine's capacity is the engine displacement , in other words the volume swept by all the pistons of an engine in a single movement. It is generally measured in litres (l) or cubic inches (c.i.d., cu in, or in ) for larger engines, and cubic centimetres (abbreviated cc) for smaller engines. All else being equal, engines with greater capacities are more powerful and consumption of fuel increases accordingly (although this

414-469: A cylinder to drive a reciprocating engine in a local-pollution-free urban vehicle. Torpedoes may use a working gas produced by high test peroxide or Otto fuel II , which pressurize without combustion. The 230 kg (510 lb) Mark 46 torpedo , for example, can travel 11 km (6.8 mi) underwater at 74 km/h (46 mph) fuelled by Otto fuel without oxidant . Quantum heat engines are devices that generate power from heat that flows from

460-418: A dozen cylinders or more. Cylinder capacities may range from 10 cm or less in model engines up to thousands of liters in ships' engines. The compression ratio affects the performance in most types of reciprocating engine. It is the ratio between the volume of the cylinder, when the piston is at the bottom of its stroke, and the volume when the piston is at the top of its stroke. The bore/stroke ratio

506-406: A hot to a cold reservoir. The mechanism of operation of the engine can be described by the laws of quantum mechanics . Quantum refrigerators are devices that consume power with the purpose to pump heat from a cold to a hot reservoir. In a reciprocating quantum heat engine, the working medium is a quantum system such as spin systems or a harmonic oscillator. The Carnot cycle and Otto cycle are

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552-469: A lack of official interest in the project, work proceeded very slowly. Flight testing was not complete until 1991 . It is one of the few turbine -powered biplane designs to date. The An-3T received its Type Certificate on 31 August 2000. Supplements to the Type Certificate included version with ski landing gear and an agricultural version. The project was revitalised in the late 1990s when it

598-405: A large number of unusual varieties of piston engines that have various claimed advantages, many of which see little if any current use: Ignition system Ignition systems are used by heat engines to initiate combustion by igniting the fuel-air mixture. In a spark ignition versions of the internal combustion engine (such as petrol engines), the ignition system creates a spark to ignite

644-399: A new fire extinguishing system; and an improvement of the external wide-spreading dispensing equipment for agricultural needs. The upgrades allowed the aircraft to be more reliable and to increase the cargo lifting capacity of the aircraft by 20%, as well as ensuring more comfortable conditions for the crew, including the lowering of the noise and vibration inside the cockpit. The rate of climb

690-572: A seal, and more heavily when higher combustion pressure moves around to their inner surfaces. It is common to classify such engines by the number and alignment of cylinders and total volume of displacement of gas by the pistons moving in the cylinders usually measured in cubic centimetres (cm or cc) or litres (l) or (L) (US: liter). For example, for internal combustion engines, single and two-cylinder designs are common in smaller vehicles such as motorcycles , while automobiles typically have between four and eight, and locomotives and ships may have

736-484: A sequence of strokes that admit and remove gases to and from the cylinder. These operations are repeated cyclically and an engine is said to be 2-stroke , 4-stroke or 6-stroke depending on the number of strokes it takes to complete a cycle. The most common type is 4-stroke, which has following cycles. The reciprocating engine developed in Europe during the 18th century, first as the atmospheric engine then later as

782-586: Is not to be confused with fuel efficiency , since high efficiency often requires a lean fuel-air ratio, and thus lower power density. A modern high-performance car engine makes in excess of 75 kW/L (1.65 hp/in ). Reciprocating engines that are powered by compressed air, steam or other hot gases are still used in some applications such as to drive many modern torpedoes or as pollution-free motive power. Most steam-driven applications use steam turbines , which are more efficient than piston engines. The French-designed FlowAIR vehicles use compressed air stored in

828-412: Is not true of every reciprocating engine), although power and fuel consumption are affected by many factors outside of engine displacement. Reciprocating engines can be characterized by their specific power , which is typically given in kilowatts per litre of engine displacement (in the U.S. also horsepower per cubic inch). The result offers an approximation of the peak power output of an engine. This

874-394: Is the fictitious pressure which would produce the same amount of net work that was produced during the power stroke cycle. This is shown by: where A p {\displaystyle A_{p}} is the total piston area of the engine, S {\displaystyle S} is the stroke length of the pistons, and V d {\displaystyle V_{d}}

920-459: Is the ratio of the diameter of the piston, or " bore ", to the length of travel within the cylinder, or "stroke". If this is around 1 the engine is said to be "square". If it is greater than 1, i.e. the bore is larger than the stroke, it is "oversquare". If it is less than 1, i.e. the stroke is larger than the bore, it is "undersquare". Cylinders may be aligned in line , in a V configuration , horizontally opposite each other, or radially around

966-425: Is the total displacement volume of the engine. Therefore: Whichever engine with the larger value of MEP produces more net work per cycle and performs more efficiently. In steam engines and internal combustion engines, valves are required to allow the entry and exit of gases at the correct times in the piston's cycle. These are worked by cams, eccentrics or cranks driven by the shaft of the engine. Early designs used

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1012-423: Is then fed through one or more, increasingly larger bore cylinders successively, to extract power from the steam at increasingly lower pressures. These engines are called compound engines . Aside from looking at the power that the engine can produce, the mean effective pressure (MEP), can also be used in comparing the power output and performance of reciprocating engines of the same size. The mean effective pressure

1058-452: The D slide valve but this has been largely superseded by piston valve or poppet valve designs. In steam engines the point in the piston cycle at which the steam inlet valve closes is called the cutoff and this can often be controlled to adjust the torque supplied by the engine and improve efficiency. In some steam engines, the action of the valves can be replaced by an oscillating cylinder . Internal combustion engines operate through

1104-420: The steam engine . These were followed by the Stirling engine and internal combustion engine in the 19th century. Today the most common form of reciprocating engine is the internal combustion engine running on the combustion of petrol , diesel , liquefied petroleum gas (LPG) or compressed natural gas (CNG) and used to power motor vehicles and engine power plants . One notable reciprocating engine from

1150-595: The 1967 model year. Also in 1967, Motorola debuted their breakerless CD system. The most famous aftermarket electronic ignition which debuted in 1965, was the Delta Mark 10 capacitive discharge ignition, which was sold assembled or as a kit. The Fiat Dino was the first production car to come standard with EI in 1968, followed by the Jaguar XJ Series 1 in 1971, Chrysler (after a 1971 trial) in 1973 and by Ford and GM in 1975. In 1967, Prest-O-Lite made

1196-749: The An-2 on Soviet farms was made in the 1970s with the WSK-Mielec M-15 Belphegor , but it failed. From 2007, the "Polyot" Production Association started to upgrade the first ten An-2s of the Russian Airborne Troops to An-3T-10 standard. The overall requirement is estimated at approximately 200 aircraft. Data from Antonov An-2 General characteristics Performance Related development Aircraft of comparable role, configuration, and era Piston engine A reciprocating engine , also often known as

1242-586: The AutoLite Electric Transistor 201 and Tung-Sol EI-4 (thyratron capacitive discharge) being available. Pontiac became the first automaker to offer an optional EI, the breakerless magnetic pulse-triggered Delcotronic, on some 1963 models; it was also available on some Corvettes . The first commercially available all solid-state (SCR) capacitive discharge ignition was manufactured by Hyland Electronics in Canada also in 1963. Ford fitted

1288-489: The World War II era was the 28-cylinder, 3,500  hp (2,600 kW) Pratt & Whitney R-4360 Wasp Major radial engine. It powered the last generation of large piston-engined planes before jet engines and turboprops took over from 1944 onward. It had a total engine capacity of 71.5 L (4,360 cu in), and a high power-to-weight ratio . The largest reciprocating engine in production at present, but not

1334-450: The company's NASCAR hemis in 1963 and 1964. Prest-O-Lite 's CD-65, which relied on capacitance discharge (CD), appeared in 1965, and had "an unprecedented 50,000 mile warranty." (This differs from the non-CD Prest-O-Lite system introduced on AMC products in 1972, and made standard equipment for the 1975 model year.) A similar CD unit was available from Delco in 1966, which was optional on Oldsmobile , Pontiac, and GMC vehicles in

1380-442: The crankshaft to trigger the ignition at the proper time. Modern automotive engines use an engine control unit (ECU), which is a single device that controls various engine functions including the ignition system and the fuel injection . This contrasts earlier engines, where the fuel injection and ignition were operated as separate systems. Gas turbine engines (including jet engines) use capacitor discharge ignition , however

1426-477: The crankshaft. Opposed-piston engines put two pistons working at opposite ends of the same cylinder and this has been extended into triangular arrangements such as the Napier Deltic . Some designs have set the cylinders in motion around the shaft, such as the rotary engine . In some steam engines, the cylinders may be of varying size with the smallest bore cylinder working the highest pressure steam. This

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1472-430: The cylinder either by ignition of a fuel air mixture ( internal combustion engine ) or by contact with a hot heat exchanger in the cylinder ( Stirling engine ). The hot gases expand, pushing the piston to the bottom of the cylinder. This position is also known as the bottom dead center (BDC), or where the piston forms the largest volume in the cylinder. The piston is returned to the cylinder top (top dead center) (TDC) by

1518-414: The early 20th century, ignition magnetos were largely replaced by induction coil ignition systems. The use of ignition magnetos is now confined mainly to engines without a battery, for example in lawnmowers and chainsaws. It is also used in modern piston-engined aircraft (even though a battery is present), to avoid the engine relying on an electrical system. As batteries became more common in cars (due to

1564-504: The electricity from the ignition coil to the correct cylinder). The Kettering system became the primary ignition system for many years in the automotive industry due to its lower cost and relative simplicity. The first electronic ignition (a cold cathode type) was tested in 1948 by Delco-Remy , while Lucas introduced a transistorized ignition in 1955, which was used on BRM and Coventry Climax Formula One engines in 1962. The aftermarket began offering EI that year, with both

1610-436: The end of the 20th century, with coil-on-plug versions of these systems becoming widespread since the 1990s. An ignition magneto (also called a high-tension magneto ) is an older type of ignition system used in spark-ignition engines (such as petrol engines). It uses a magneto and a transformer to make pulses of high voltage for the spark plugs. The older term "high-tension" means "high-voltage". Used on many cars in

1656-579: The engine cycle. In the Model T, the four-cylinder engine had a trembler coil for each cylinder. An improved ignition system was invented by Charles Kettering at Delco in the United States and introduced in Cadillac's 1912 cars. The Kettering ignition system consisted of a single ignition coil, breaker points, a capacitor (to prevent the points from arcing at break) and a distributor (to direct

1702-425: The exhaust stroke while the other fires at the usual time, a so-called " wasted spark " arrangement which has no drawbacks apart from faster spark plug erosion; the paired cylinders are 1/4 and 2/3 on four cylinder arrangements, 1/4, 6/3, 2/5 on six cylinder engines and 6/7, 4/1, 8/3 and 2/5 on V8 engines. Other systems do away with the distributor as a timing apparatus and use a magnetic crank angle sensor mounted on

1748-622: The fuel-air mixture just before each combustion stroke . Gas turbine engines and rocket engines normally use an ignition system only during start-up. Diesel engines use compression ignition to ignite the fuel-air mixture using the heat of compression and therefore do not use an ignition system. They usually have glowplugs that preheat the combustion chamber to aid starting in cold weather. Early cars used ignition magneto and trembler coil systems, which were superseded by Distributor -based systems (first used in 1912). Electronic ignition systems (first used in 1968) became common towards

1794-400: The increased usage of electric starter motors), magneto systems were replaced by systems using an induction coil . The 1886 Benz Patent-Motorwagen and the 1908 Ford Model T used a trembler coil ignition system, whereby the trembler interrupted the current through the coil and caused a rapid series of sparks during each firing. The trembler coil would be energized at an appropriate point in

1840-604: The largest ever built, is the Wärtsilä-Sulzer RTA96-C turbocharged two-stroke diesel engine of 2006 built by Wärtsilä . It is used to power the largest modern container ships such as the Emma Mærsk . It is five stories high (13.5 m or 44 ft), 27 m (89 ft) long, and weighs over 2,300 metric tons (2,535 short tons ; 2,264 long tons ) in its largest 14 cylinders version producing more than 84.42 MW (113,209 bhp). Each cylinder has

1886-407: The mechanical system. The lack of moving parts compared with the mechanical system leads to greater reliability and longer service intervals. A variation coil-on-plug ignition has each coil handle two plugs, on cylinders which are 360 degrees out of phase (and therefore reach top dead center (TDC) at the same time); in the four-cycle engine this means that one plug will be sparking during the end of

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1932-410: The ones most studied. The quantum versions obey the laws of thermodynamics . In addition, these models can justify the assumptions of endoreversible thermodynamics . A theoretical study has shown that it is possible and practical to build a reciprocating engine that is composed of a single oscillating atom. This is an area for future research and could have applications in nanotechnology . There are

1978-505: The same sealed quantity of gas. The stroke is simply the distance between the TDC and the BDC, or the greatest distance that the piston can travel in one direction. In some designs the piston may be powered in both directions in the cylinder, in which case it is said to be double-acting . In most types, the linear movement of the piston is converted to a rotating movement via a connecting rod and

2024-407: The sliding piston and the walls of the cylinder so that the high pressure gas above the piston does not leak past it and reduce the efficiency of the engine. This seal is usually provided by one or more piston rings . These are rings made of a hard metal, and are sprung into a circular groove in the piston head. The rings fit closely in the groove and press lightly against the cylinder wall to form

2070-620: Was increased by 1.9 times, and the take-off and landing performance of the aircraft was increased. The upgrading allowed the use of kerosene and lubricants commonly used for other aircraft instead of gasoline. The take-off weight and payload was also increased and the upgrade allowed the landing performance to use ground strips 500 metres (1,600 ft) long. The upgrading was arranged at both the "Polyot" Production Association in Omsk, Russian Federation, and at Antonov ASTC , Kyiv, Ukraine. The first example flew as early as May 13, 1980, but because of

2116-454: Was taken over by Polyot State Aerospace Enterprise , and a marketing campaign began in earnest in 2000 , although sales have been limited. It is available in four forms, the basic transport version ( An-3T ), the convertible cargo/passenger able to carry 12 passengers or 1,800 kg (4,000 lb) of cargo (An-3TK)k the agricultural aircraft ( An-3SH —"Selsko-Khosiajstwenni") and the fire-fighting version ( An-3P ). Another attempt to replace

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