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Thrust Curve
A thrust curve, sometimes known as a "performance curve" or "thrust profile" is a graph of the thrust of an engine or motor, (usually a rocket) with respect to time. Most engines do not produce linear thrust (thrust which increases at a constant rate with time). Instead, they produce a curve of some type, where thrust will slowly rise to a peak, and then fall, or "tail off". Richard Nakka's Experimental Rocketry Web Site"Solid Rocket Motor Theory -- Chamber Pressure"/ref> Rocket engines 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 accordanc ..., particularly solid-fuel rocket engines, produce very consistent thrust curves, making this a useful metric for judging their performance. This information is vital when designing spacecraft, particularly multistage spacecraft, since it may be ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estes
Estes is an English-language surname said to derive from Old English and have the meaning "of the East" (literally, "East's"). As a surname, it has been traced to southern Kent, as early as the mid-15th century, Nicholas Estes (Ewstas, Esteuzi) b. 1475 Deal, Kent, England, d. 1506 Dover, Kent, England. Notable people with the surname include: * Billie Sol Estes, Texas businessman and politician * Bob Estes, U.S. professional golf player * Bradley Estes, U.S. neuropsychologist * David H Estes, United States Attorney, Southern District of Georgia * Eleanor Estes, U.S. children's author * James A. Estes U.S. ecologist * Jim Estes, U.S. golfer * John Estes, U.S. football player * Lauren Estes, Vocaloid Producer * Sleepy John Estes, John Adam Estes, also known as "Sleepy John" Estes, U.S. blues musician * John Curtis Estes, birth name of adult film star John Holmes (pornographic actor), John Holmes * Patrick Estes, U.S. football player * Richard Estes, U.S. photorealist painter * Richard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engine
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power generation), heat energy (e.g. geothermal), chemical energy, electric potential and nuclear energy (from nuclear fission or nuclear fusion). Many of these processes generate heat as an intermediate energy form, so heat engines have special importance. Some natural processes, such as atmospheric convection cells convert environmental heat into motion (e.g. in the form of rising air currents). Mechanical energy is of particular importance in transportation, but also plays a role in many industrial processes such as cutting, grinding, crushing, and mixing. Mechanical heat engines convert heat into work via various thermodynamic processes. The internal combustion engine is perhaps the most common example of a mechanical heat engine, in which he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocket Engines
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. Compared to other types of jet engine, rocket engines are the lightest and have the highest thrust, but are the least propellant-efficient (they have the lowest specific impulse). The ideal exhaust is hydrogen, the lightest of all elements, but chemical rockets produce a mix of heavier species, reducing the ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid-fuel Rocket
A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants ( fuel/oxidizer). The earliest rockets were solid-fuel rockets powered by gunpowder; they were used in warfare by the Arabs, Chinese, Persians, Mongols, and Indians as early as the 13th century. All rockets used some form of solid or powdered propellant up until the 20th century, when liquid-propellant rockets offered more efficient and controllable alternatives. Solid rockets are still used today in military armaments worldwide, model rockets, solid rocket boosters and on larger applications for their simplicity and reliability. Since solid-fuel rockets can remain in storage for an extended period without much propellant degradation and because they almost always launch reliably, they have been frequently used in military applications such as missiles. The lower performance of solid propellants (as compared to liquids) does not favor their use as primary propulsion in mode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multistage Rocket
A multistage rocket or step rocket is a launch vehicle that uses two or more rocket ''stages'', each of which contains its own engines and propellant. A ''tandem'' or ''serial'' stage is mounted on top of another stage; a ''parallel'' stage is attached alongside another stage. The result is effectively two or more rockets stacked on top of or attached next to each other. Two-stage rockets are quite common, but rockets with as many as five separate stages have been successfully launched. By jettisoning stages when they run out of propellant, the mass of the remaining rocket is decreased. Each successive stage can also be optimized for its specific operating conditions, such as decreased atmospheric pressure at higher altitudes. This ''staging'' allows the thrust of the remaining stages to more easily accelerate the rocket to its final speed and height. In serial or tandem staging schemes, the first stage is at the bottom and is usually the largest, the second stage and subseq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
