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Jet Engine Performance
A jet engine converts fuel into thrust. One key metric of performance is the thermal efficiency; how much of the chemical energy (fuel) is turned into useful work (thrust propelling the aircraft at high speeds). Like a lot of heat engines, jet engines tend to not be particularly efficient (<50%); a lot of the fuel is "wasted". In the 1970s, economic pressure due to the rising cost of fuel resulted in increased emphasis on efficiency improvements for commercial airliners. Jet engine performance has been phrased as 'the end product that a jet engine company sells' and, as such, criteria include thrust, (specific) fuel consumption, time between overhauls, power-to-weight ratio. Some major factors affecting efficiency include the engine's overall pressure ratio, its bypass ratio and the turbine inlet temperature. Performance criteria reflect the level of technology used in the design of an engine, and the technology has been advancing continuously since the jet engine entered service i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Efficiency
In thermodynamics, the thermal efficiency (\eta_) is a dimensionless performance measure of a device that uses thermal energy, such as an internal combustion engine, steam turbine, steam engine, boiler, furnace, refrigerator, ACs etc. For a heat engine, thermal efficiency is the ratio of the net work output to the heat input; in the case of a heat pump, thermal efficiency (known as the '' coefficient of performance'' or COP) is the ratio of net heat output (for heating), or the net heat removed (for cooling) to the energy input (external work). The efficiency of a heat engine is fractional as the output is always less than the input while the COP of a heat pump is more than 1. These values are further restricted by the Carnot theorem. Overview In general, energy conversion efficiency is the ratio between the useful output of a device and the input, in energy terms. For thermal efficiency, the input, Q_, to the device is heat, or the heat-content of a fuel that is c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbojet
The turbojet is an airbreathing jet engine which is typically used in aircraft. It consists of a gas turbine with a propelling nozzle. The gas turbine has an air inlet which includes inlet guide vanes, a compressor, a combustion chamber, and a turbine (that drives the compressor). The compressed air from the compressor is heated by burning fuel in the combustion chamber and then allowed to expand through the turbine. The turbine exhaust is then expanded in the propelling nozzle where it is accelerated to high speed to provide thrust. Two engineers, Frank Whittle in the United Kingdom and Hans von Ohain in Germany, developed the concept independently into practical engines during the late 1930s. Turbojets have poor efficiency at low vehicle speeds, which limits their usefulness in vehicles other than aircraft. Turbojet engines have been used in isolated cases to power vehicles other than aircraft, typically for attempts on land speed records. Where vehicles are "turbine-powere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ECAM
ECAM may refer to: * Electronic centralised aircraft monitor, a system that monitors aircraft functions and relays them to the pilots * ''Evidence-Based Complementary and Alternative Medicine'', a medical journal * École Catholique des Arts et Métiers, an engineering school in Lyon, France * ECAM Rennes - Louis de Broglie ECAM may refer to: * Electronic centralised aircraft monitor, a system that monitors aircraft functions and relays them to the pilots * ''Evidence-Based Complementary and Alternative Medicine'', a medical journal * École Catholique des Arts et M� ..., an engineering school in Rennes, France * The Madrid Film School (), a film school in Madrid, Spain See also * {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Box
In science, computing, and engineering, a black box is a system which can be viewed in terms of its inputs and outputs (or transfer characteristics), without any knowledge of its internal workings. Its implementation is "opaque" (black). The term can be used to refer to many inner workings, such as those of a transistor, an engine, an algorithm, the human brain, or an institution or government. To analyze an open system with a typical "black box approach", only the behavior of the stimulus/response will be accounted for, to infer the (unknown) ''box''. The usual representation of this "black box system" is a data flow diagram centered in the box. The opposite of a black box is a system where the inner components or logic are available for inspection, which is most commonly referred to as a white box (sometimes also known as a "clear box" or a "glass box"). History The modern meaning of the term "black box" seems to have entered the English language around 1945. In electroni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rolls-Royce BR700
The Rolls-Royce BR700 is a family of turbofan engines for regional jets and corporate jets. It is manufactured in Dahlewitz, Germany, by Rolls-Royce Deutschland: this was initially a joint venture of BMW and Rolls-Royce plc established in 1990 to develop this engine. The BR710 first ran in 1995. The United States military designation for the BR725 variant is F130. Design and development BR710 The BR710 is a twin shaft turbofan, and entered service on the Gulfstream V in 1997 in aviation, 1997 and the Bombardier Global Express in 1998. This version has also been selected to power the Gulfstream G550. The BR710 comprises a diameter single-stage fan, driven by a two-stage LP turbine, and a ten-stage HP compressor (scaled from the V2500 unit) driven by a two-stage, air-cooled, HP turbine. This engine has a thrust-specific fuel consumption (TSFC) of at static sea level takeoff and at a cruise speed of Mach number, Mach 0.8 and altitude of . In May 2017, the 3,200 engines in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbo-Union RB199
The Turbo-Union RB199 is a turbofan jet engine designed and built in the early 1970s by Turbo-Union, a joint venture between Rolls-Royce, MTU and Aeritalia. The only production application was the Panavia Tornado, but it was used in the British Aerospace EAP whose 1st flight was on 8 August 1986 from Warton, without use of a spare engine on its total 259 flights, and is now in RAF Cosford Museum. It was also used in the first two Prototypes of the Eurofighter Typhoon, whose 1st flight, by DA1, was from Manching, Bavaria on 27 March 1994, and for a further two years before the EJ200 engines were installed - good reliability meant the spare RB199 engine supplied was never used. Design and development The RB199 originated with a requirement, in 1969, to power a new European multirole combat aircraft (MRCA) called the Panavia MRCA. The engine requirements to meet the Panavia MRCA specification were significant advances over current engines in thrust-to-weight ratio, fuel con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IAE V2500
The IAE V2500 is a two-shaft high-bypass turbofan engine built by International Aero Engines (IAE) which powers the Airbus A320 family, the McDonnell Douglas MD-90, and the Embraer C-390 Millennium. The engine's name is a combination of the Roman numeral ''V'', symbolizing the five original members of the International Aero Engines consortium, formed in 1983 to produce the engine, and ''2500'', which represents the thrust produced by the original engine model, the V2500-A1. FAA type certification for the V2500 was granted in 1988. The maintenance, repair, and operations market for the V2500 is close to as of 2015. Development Rolls-Royce based the ten-stage high-pressure compressor on an eight-stage run in the RB401 in the mid 1970s followed by a nine-stage run in the RJ.500. The V.2500 would use ten stages, with the first four with variable stators, giving a pressure ratio of 20:1. A single-stage booster was also part of the original configuration. Serious handling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CFM International CFM56
The CFM International CFM56 (U.S. military designation F108) series is a Franco-American family of high-bypass turbofan aircraft engines made by CFM International (CFMI), with a thrust range of . CFMI is a 50–50 joint-owned company of Safran Aircraft Engines (formerly known as Snecma) of France, and GE Aerospace (GE) of the United States. GE produces the high-pressure compressor, combustor, and high-pressure Components of jet engines#Turbines, turbine, Safran manufactures the fan, Transmission (mechanics), gearbox, Nozzle, exhaust and the low-pressure turbine, and some components are made by Avio of Italy and Honeywell from the US. Both companies have their own final assembly line, GE in Evendale, Ohio, and Safran in Melun Villaroche Aerodrome, Villaroche, France. The engine initially had extremely slow sales but has gone on to become the most used turbofan aircraft engine in the world. The CFM56 first ran in 1974. By April 1979, the joint venture had not received a single ord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klimov VK-1
The Klimov VK-1 was the first Soviet jet engine to see significant production. It was developed by and first produced by the GAZ 116 works. Derived from the Rolls-Royce Nene, the engine was also built under licence in China as the Wopen WP-5. Design and development Immediately after World War II, the Soviet Union manufactured copies of first generation German Junkers 004 and BMW 003 engines, which were advanced designs with poor durability, limited by Germany's shortage of rare metals in wartime. However, in 1946, before the Cold War had really begun, the new British Labour government under the prime minister, Clement Attlee, keen to improve diplomatic relations with the Soviet Union, authorised Rolls-Royce to export 40 Rolls-Royce Nene centrifugal flow turbojet engines. In 1958 it was discovered during a visit to Beijing by Whitney Straight, then deputy chairman of Rolls-Royce, that this engine had been copied without license to power the MiG-15 'Fagot', first as the RD-4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pratt & Whitney J57
The Pratt & Whitney J57 (company designation: JT3C) is an axial-flow turbojet engine developed by Pratt & Whitney in the early 1950s. The J57 (first run January 1950) was the first 10,000 lbf (45 kN) thrust class engine in the United States. It is a two spool engine. The J57/JT3C was developed into the J52 turbojet, the J75/JT4A turbojet, the JT3D/TF33 turbofan, and the XT57 turboprop (of which only one was built). The J57 and JT3C saw extensive use on fighter jets, jetliners, and bombers for many decades. Design and development The J57 was a development of the Pratt & Whitney XT45 (PT4) turboprop engine that was originally intended for the Boeing XB-52. As the B-52 power requirements grew, the design evolved into a turbojet, the JT3. Pratt & Whitney designed the J57 to have a relatively high overall pressure ratio to help improve both thrust-specific fuel consumption and specific thrust, but it was known that throttling a single high-pressure-ratio compressor w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sankey Diagram
Sankey diagrams are a data visualisation technique or flow diagram that emphasizes flow/movement/change from one state to another or one time to another, in which the width of the arrows is proportional to the flow rate of the depicted extensive property. The arrows being connected are called nodes and the connections are called links. Sankey diagrams can also visualize the energy accounts, material flow accounts on a regional or national level, and cost breakdowns. The diagrams are often used in the visualization of material flow analysis. Sankey diagrams emphasize the major transfers or flows within a system. They help locate the most important contributions to a flow. They often show conserved quantities within defined system boundaries. History and name Sankey diagrams are named after Irish Captain Matthew Henry Phineas Riall Sankey, who used this type of diagram in 1898 in a classic figure (see diagram) showing the energy efficiency of a steam engine. The original chart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frank Whittle
Air Commodore Sir Frank Whittle, (1 June 1907 – 8 August 1996) was an English engineer, inventor and Royal Air Force (RAF) air officer. He is credited with co-creating the turbojet engine. A patent was submitted by Maxime Guillaume in 1921 for a similar invention which was technically unfeasible at the time. Whittle's jet engines were developed some years earlier than those of Germany's Hans von Ohain, who designed the first-to-fly turbojet engine as well as Austria’s Anselm Franz. Whittle demonstrated an aptitude for engineering and an interest in flying from an early age. At first he was turned down by the RAF but, determined to join the force, he overcame his physical limitations and was accepted and sent to No. 2 School of Technical Training to join No 1 Squadron of Cranwell Aircraft Apprentices. He was taught the theory of aircraft engines and gained practical experience in the engineering workshops. His academic and practical abilities as an Aircraft Apprentice earned ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
