Related Research Articles
A jet engine is a type of reaction engine, discharging a fast-moving jet of heated gas that generates thrust by jet propulsion. While this broad definition may include rocket, water jet, and hybrid propulsion, the term jet engine typically refers to an internal combustion air-breathing jet engine such as a turbojet, turbofan, ramjet, or pulse jet. In general, jet engines are internal combustion engines.
A ramjet, or athodyd, is a form of airbreathing jet engine that uses the forward motion of the engine to take in air for combustion that produces jet thrust. Since it produces no thrust when stationary ramjet-powered vehicles require an assisted take-off like a rocket assist to accelerate it to a speed where it begins to produce thrust. Ramjets work most efficiently at supersonic speeds around Mach 3 and can operate up to speeds of Mach 6.
A turbopump is a propellant pump with two main components: a rotodynamic pump and a driving gas turbine, usually both mounted on the same shaft, or sometimes geared together. They were initially developed in Germany in the early 1940s. The purpose of a turbopump is to produce a high-pressure fluid for feeding a combustion chamber or other use. While other use cases exist, they are most commonly found in liquid rocket engines.
Specific impulse is a measure of how efficiently a reaction mass engine creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse is exactly proportional to the effective exhaust gas velocity.
A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other.
Monopropellants are propellants consisting of chemicals that release energy through exothermic chemical decomposition. The molecular bond energy of the monopropellant is released usually through use of a catalyst. This can be contrasted with bipropellants that release energy through the chemical reaction between an oxidizer and a fuel. While stable under defined storage conditions, monopropellants decompose very rapidly under certain other conditions to produce a large volume of its own energetic (hot) gases for the performance of mechanical work. Although solid deflagrants such as nitrocellulose, the most commonly used propellant in firearms, could be thought of as monopropellants, the term is usually reserved for liquids in engineering literature.
A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accordance with Newton's third law. Most rocket engines use the combustion of reactive chemicals to supply the necessary energy, but non-combusting forms such as cold gas thrusters and nuclear thermal rockets also exist. Vehicles propelled by rocket engines are commonly called rockets. Rocket vehicles carry their own oxidiser, unlike most combustion engines, so rocket engines can be used in a vacuum to propel spacecraft and ballistic missiles.
A propellant is a mass that is expelled or expanded in such a way as to create a thrust or another motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the engine that expels the propellant is called a reaction engine. Although technically a propellant is the reaction mass used to create thrust, the term "propellant" is often used to describe a substance which contains both the reaction mass and the fuel that holds the energy used to accelerate the reaction mass. For example, the term "propellant" is often used in chemical rocket design to describe a combined fuel/propellant, although the propellants should not be confused with the fuel that is used by an engine to produce the energy that expels the propellant. Even though the byproducts of substances used as fuel are also often used as a reaction mass to create the thrust, such as with a chemical rocket engine, propellant and fuel are two distinct concepts.
A liquid-propellant rocket or liquid rocket utilizes a rocket engine that uses liquid propellants. Gaseous propellants may also be used but are not common because of their low density and difficulty with common pumping methods. Liquids are desirable because they have a reasonably high density and high specific impulse (Isp). This allows the volume of the propellant tanks to be relatively low. The rocket propellants are usually pumped into the combustion chamber with a lightweight centrifugal turbopump, although some aerospace companies have found ways to use electric pumps with batteries, allowing the propellants to be kept under low pressure. This permits the use of low-mass propellant tanks that do not need to resist the high pressures needed to store significant amounts of gasses, resulting in a low mass ratio for the rocket.
SABRE is a concept under development by Reaction Engines Limited for a hypersonic precooled hybrid air-breathing rocket engine. The engine is being designed to achieve single-stage-to-orbit capability, propelling the proposed Skylon spaceplane to low Earth orbit. SABRE is an evolution of Alan Bond's series of LACE-like designs that started in the early/mid-1980s for the HOTOL project.
A jet pack, rocket belt, or rocket pack is a device worn on the back which uses jets of gas or liquid to propel the wearer through the air. The concept has been present in science fiction for almost a century and became widespread in the 1960s.
The highest specific impulse chemical rockets use liquid propellants. They can consist of a single chemical or a mix of two chemicals, called bipropellants. Bipropellants can further be divided into two categories; hypergolic propellants, which ignite when the fuel and oxidizer make contact, and non-hypergolic propellants which require an ignition source.
The RBCC, or rocket-based combined cycle propulsion system, was one of the two types of propulsion systems that may have been tested in the Boeing X-43 experimental aircraft. The RBCC, or strutjet as it is sometimes called, is a combination propulsion system that consists of a ramjet, scramjet, and ducted rocket, where all three systems use a shared flow path.
Jet propulsion is the propulsion of an object in one direction, produced by ejecting a jet of fluid in the opposite direction. By Newton's third law, the moving body is propelled in the opposite direction to the jet. Reaction engines operating on the principle of jet propulsion include the jet engine used for aircraft propulsion, the pump-jet used for marine propulsion, and the rocket engine and plasma thruster used for spacecraft propulsion. Underwater jet propulsion is also used by several marine animals, including cephalopods and salps, with the flying squid even displaying the only known instance of jet-powered aerial flight in the animal kingdom.
A gas generator is a device for generating gas. A gas generator may create gas by a chemical reaction or from a solid or liquid source, when storing a pressurized gas is undesirable or impractical.
A rocket car is a land vehicle propelled by a rocket engine. A rocket dragster is a rocket car used for competing in drag racing, and this type holds the unofficial world record for the 1/4 mile.
The Armstrong Siddeley, later Bristol SiddeleyGamma was a family of rocket engines used in British rocketry, including the Black Knight and Black Arrow launch vehicles. They burned kerosene fuel and hydrogen peroxide. Their construction was based on a common combustion chamber design, used either singly or in clusters of up to eight.
Rocket propellant is the reaction mass of a rocket. This reaction mass is ejected at the highest achievable velocity from a rocket engine to produce thrust. The energy required can either come from the propellants themselves, as with a chemical rocket, or from an external source, as with ion engines.
Space Engine Systems Inc. (SES) is a Canadian aerospace company and is located in Edmonton, Alberta, Canada. The main focus of the company is the development of a light multi-fuel propulsion system to power a reusable single-stage-to-orbit (SSTO) and hypersonic cruise vehicle. Pumps, compressors, gear boxes, and other related technologies being developed are integrated into SES's major R&D projects. SES has collaborated with the University of Calgary to study and develop technologies in key technical areas of nanotechnology and high-speed aerodynamics.
Aircraft engine performance refers to factors including thrust or shaft power for fuel consumed, weight, cost, outside dimensions and life. It includes meeting regulated environmental limits which apply to emissions of noise and chemical pollutants, and regulated safety aspects which require a design that can safely tolerate environmental hazards such as birds, rain, hail and icing conditions. It is the end product that an engine company sells.
References
- ↑ "Analysis of the effect of factors on the efficiency of liquid rocket turbine" by Zu, Guojun; Zhang, Yuanjun Journal of Propulsion Technology no. 6, p. 38-43, 58.
- ↑ Hydrogen peroxide based propulsion system for micro air vehicle applications b WS Cheung, JR Tilston ISABE 99-7298 "Hydrogen Peroxide Based Propulsion System for Micro Air Vehicle Applications" (PDF). Archived from the original (PDF) on 2011-07-11. Retrieved 2011-03-10.
- ↑ "Testing of a novel propulsion system for micro air vehicles". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering. 215 (4): 207–218. 2001. Retrieved April 8, 2023.
| Concepts | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Physical propulsion | |||||||||
| Chemical propulsion |
| ||||||||
| Electrical propulsion |
| ||||||||
| Nuclear propulsion |
| ||||||||
| External power | |||||||||
| Related concepts | |||||||||
| Liquid fuel |
|  | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solid fuel |
| |||||||||||||||||
| ||||||||||||||||||
 | This technology-related article is a stub. You can help Wikipedia by expanding it. |
 | This rocketry article is a stub. You can help Wikipedia by expanding it. |
 | This aviation-related article is a stub. You can help Wikipedia by expanding it. |