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SABRE (rocket Engine)
SABRE (Synergetic Air Breathing Rocket Engine) was a concept under development by Reaction Engines Limited for a hypersonic precooled hybrid air-breathing rocket engine. The engine was designed to achieve single-stage-to-orbit capability, propelling the proposed Skylon spaceplane to low Earth orbit. SABRE was an evolution of Alan Bond's series of LACE-like designs that started in the early/mid-1980s for the HOTOL project. Reaction Engines went into bankruptcy in 2024 before completing the project. The design comprised a single combined cycle rocket engine with two modes of operation. The air-breathing mode combined a turbo-compressor with a lightweight air precooler positioned just behind the inlet cone. At high speeds this precooler would cool the hot, ram-compressed air, which would otherwise reach a temperature that the engine could not withstand, leading to a very high pressure ratio within the engine. The compressed air would subsequently be fed into the rocket combu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotland, Wales and Northern Ireland. The UK includes the island of Great Britain, the north-eastern part of the island of Ireland, and most of List of islands of the United Kingdom, the smaller islands within the British Isles, covering . Northern Ireland shares Republic of Ireland–United Kingdom border, a land border with the Republic of Ireland; otherwise, the UK is surrounded by the Atlantic Ocean, the North Sea, the English Channel, the Celtic Sea and the Irish Sea. It maintains sovereignty over the British Overseas Territories, which are located across various oceans and seas globally. The UK had an estimated population of over 68.2 million people in 2023. The capital and largest city of both England and the UK is London. The cities o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Air Cycle Engine
A liquid air cycle engine (LACE) is a type of spacecraft propulsion engine that attempts to increase its efficiency by gathering part of its oxidizer from the atmosphere. A liquid air cycle engine uses liquid hydrogen (LH2) fuel to liquefy the air. In a liquid oxygen/liquid hydrogen rocket, the liquid oxygen (LOX) needed for combustion is the majority of the weight of the spacecraft on lift-off, so if some of this can be collected from the air on the way, it might dramatically lower the take-off weight of the spacecraft. LACE was studied to some extent in the USA during the late 1950s and early 1960s, and by late 1960 Marquardt had a testbed system running. However, as NASA moved to ballistic capsules during Project Mercury, funding for research into winged vehicles slowly disappeared, and LACE work along with it. LACE was also the basis of the engines on the British Aerospace HOTOL design of the 1980s, but this did not progress beyond studies. Principle of operation Conc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supersonic Transport
The ogive.html" ;"title="Concorde supersonic transport had an ogive">ogival delta wing, a slender fuselage and four underslung Rolls-Royce/Snecma Olympus 593 engines. file:Tu-144.jpg, The Tupolev Tu-144 was the first SST to enter service and the first to leave it. Only 55 passenger flights were carried out before service ended due to safety concerns. A small number of cargo and test flights were also carried out after its retirement. A supersonic transport (SST) or a supersonic airliner is a Civil aviation, civilian supersonic aircraft designed to transport passengers at speeds greater than the speed of sound in terms of air speed. To date, the only SSTs to see regular service have been Concorde and the Tupolev Tu-144. The last passenger flight of the Tu-144 was in June 1978 and it was last flown in 1999 by NASA. Concorde's last commercial flight was in October 2003, with a November 26, 2003 ferry flight being its last flight. Following the termination of flying by Concorde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reaction Engines A2
LAPCAT (Long-Term Advanced Propulsion Concepts and Technologies) was a 36-month European FP6 study to examine ways to produce engines for a Mach number 4-8 hypersonic flight aircraft. The project ended in April 2008. It was funded by the European Commission research and development fund (rather than ESA), and cost 7 million euros. LAPCAT II, a 10 million euro, four-year, follow on project, started in October 2008. The study aims to refine some of the results of the first study "allowing the definition of a detailed development roadmap" of a Mach five vehicle. Objectives Two major technologies were to be considered: * ram-compression, which needs an additional propulsion system to achieve its minimum working speed. * active compression, which has an upper Mach number limitation but can accelerate a vehicle up to its cruise speed. Key objectives were the definition and evaluation of: * different propulsion cycles and concepts for high-speed flight at Mach 4 to 8 such as turbin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reaction Engines Scimitar
The Reaction Engines Scimitar is a derivative of the SABRE engine technology, but intended for jet airliners (the Reaction Engines LAPCAT A2 concept), rather than space launch applications. Consequently, most of the Scimitar engine technology is similar to SABRE but designed for much longer life. Both engines are designed around existing ramjet technology, but the Scimitar engine lacks the rocket features and has high bypass features for greater efficiency. The engines burn liquid hydrogen as fuel. The incorporation of lightweight heat exchangers in the main thermodynamic cycles of these engines is a new feature to aerospace propulsion. Similar studies of intercooler An intercooler is a heat exchanger used to cool a gas after compression. Often found in turbocharged engines, intercoolers are also used in air compressors, air conditioners, refrigeration and gas turbines. Internal combustion engines Mo ...s used on jet engines show significant improvement of efficiency. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staged Combustion Cycle (rocket)
The staged combustion cycle (sometimes known as topping cycle, preburner cycle, or closed cycle) is a power cycle of a bipropellant rocket engine. In the staged combustion cycle, propellant flows through multiple combustion chambers, and is thus combusted in stages. The main advantage relative to other rocket engine power cycles is high fuel efficiency, measured through specific impulse, while its main disadvantage is engineering complexity. Typically, propellant flows through two kinds of combustion chambers; the first called and the second called . In the preburner, a small portion of propellant, usually fuel-rich, is partly combusted under non- stoichiometric conditions, increasing the volume of flow driving the turbopumps that feed the engine with propellant. The gas is then injected into the main combustion chamber and combusted completely with the other propellant to produce thrust. Tradeoffs The main advantage is fuel efficiency due to all of the propellant flowin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mach Number
The Mach number (M or Ma), often only Mach, (; ) is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a boundary to the local speed of sound. It is named after the Austrian physicist and philosopher Ernst Mach. \mathrm = \frac, where: * is the local Mach number, * is the local flow velocity with respect to the boundaries (either internal, such as an object immersed in the flow, or external, like a channel), and * is the speed of sound in the medium, which in air varies with the square root of the thermodynamic temperature. By definition, at Mach1, the local flow velocity is equal to the speed of sound. At Mach0.65, is 65% of the speed of sound (subsonic), and, at Mach1.35, is 35% faster than the speed of sound (supersonic). The local speed of sound, and hence the Mach number, depends on the temperature of the surrounding gas. The Mach number is primarily used to determine the approximation with which a flow can be treated as an i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Air
Liquid Air was the marque of an automobile planned by Liquid Air Power and Automobile Co. of Boston and New York City in 1899. page 1432 A factory location was acquired in Boston, Massachusetts in 1899 and Liquid Air claimed they would construct a car that would run a hundred miles on liquid air. In 1901 the company had gone into receivership with declared capital stock of $1,500,000 but assets of only $7,500. See also *Alternative fuel vehicle *Compressed-air vehicle *Liquid nitrogen vehicle References {{reflist Defunct motor vehicle manufacturers of the United States Alternative fuels Veteran vehicles 1900s cars Vehicle manufacturing companies established in 1899 Vehicle manufacturing companies disestablished in 1901 Motor vehicle manufacturers based in Massachusetts Motor vehicle manufacturers based in New York (state) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion Chamber
A combustion chamber is part of an internal combustion engine in which the air–fuel ratio, fuel/air mix is burned. For steam engines, the term has also been used for an extension of the Firebox (steam engine), firebox which is used to allow a more complete combustion process. Internal combustion engines In an internal combustion engine, the pressure caused by the burning air/fuel mixture applies direct force to part of the engine (e.g. for a piston engine, the force is applied to the top of the piston), which converts the gas pressure into mechanical energy (often in the form of a rotating output shaft). This contrasts an external combustion engine, where the combustion takes place in a separate part of the engine to where the gas pressure is converted into mechanical energy. Spark-ignition engines In spark ignition engines, such as petrol engine, petrol (gasoline) engines, the combustion chamber is usually located in the cylinder head. The engines are often designed such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overall Pressure Ratio
In aeronautical engineering, overall pressure ratio, or overall compression ratio, is the amount of times the pressure increases due to ram compression and the work done by the compressor stages. The compressor pressure ratio is the ratio of the stagnation pressures at the front and rear of the compressor of a gas turbine. Overall pressure ratio in a high-bypass turbofan is a function of inlet pressure ratio and compressor pressure ratio: OPR = IPR \times CPR The terms ''compression ratio'' and ''pressure ratio'' are used interchangeably. Advantages of high overall pressure ratios As can be seen in the formula for maximum theoretical thermal efficiency in an ideal Brayton cycle engine, a high pressure ratio leads to higher thermal efficiency: \eta = 1-\left(\frac\right) where PR is the pressure ratio and gamma the heat capacity ratio of the fluid, 1.4 for air. Keep in mind that pressure ratio scales exponentially with the number of compressor stages. Imagine a gas turbin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inlet Cone
Inlet cones (sometimes called shock cones or inlet centerbodies) are a component of some supersonic aircraft and missiles. They are primarily used on ramjets, such as the D-21 Tagboard and Lockheed X-7. Some turbojet aircraft including the Su-7, MiG-21, English Electric Lightning, and SR-71 also use an inlet cone. Purpose An inlet cone, as part of an Oswatitsch-type inlet used on a supersonic aircraft or missile, is the 3D-surface on which supersonic ram compression for a gas turbine engine or ramjet combustor takes place through oblique shock waves. Slowing the air to low supersonic speeds using a cone minimizes loss in total pressure (increases pressure recovery). Also, the cone, together with the inlet cowl lip, determine the area which regulates the flow entering the inlet. If the flow is more than that required by the engine then shock position instability (buzz) can occur. If less than that required then the pressure recovery is lower which reduces engine thrust. An in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precooled Jet Engine
A precooled jet engine is a concept that enables jet engines with turbomachinery, as opposed to ramjets, to be used at high speeds. Precooling restores some or all of the performance degradation of the engine compressor (by preventing rotating stall/choking/reduced flow), as well as that of the complete gas generator (by maintaining a significant combustor temperature rise within a fixed turbine temperature limit), which would otherwise prevent flight with high ram temperatures. History Robert P. Carmichael in 1955 devised several engine cycles that used liquid hydrogen to precool the inlet air to the engine before using it as fuel. Interest in precooled engines saw an emergence in the UK in 1982, when Alan Bond (engineer), Alan Bond created a precooled air breathing rocket engine design he called SATAN. The idea was developed as part of the HOTOL SSTO spaceplane project, and became the Rolls-Royce RB545. In 1989, after the HOTOL project was discontinued, some of the RB545 engi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
