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A ramjet is a form of jet engine that contains no major moving parts and can be particularly useful in applications requiring a small and simple engine for high-speed use, such as with missiles.
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ramjet and is
* ramjet assisted, similar to rocket assisted but using a ramjet instead of a rocket motor ; it is anticipated that a ramjet-assisted 120-mm mortar shell could reach a range of.
Home is resettled quickly though, since another ramjet with colonists is already on its way when the colony " fails ".
The heart of an actual ramjet — a miles-wide electromagnetic field — is invisible.
The Bussard ramjet is a theoretical method of spacecraft propulsion proposed in 1960 by the physicist Robert W. Bussard, popularized by Poul Andersons novel Tau Zero, Larry Niven in his Known Space series of books, Vernor Vinge in his Zones of Thought series, and referred to by Carl Sagan in the television series and book Cosmos.
# The thrust to mass ratio of the ramjet, which is: A
# How long the ramjet is actually able to remain under thrust before it breaks down.
Such an ion scoop will use electromagnetic funnels, or electrostatic fields to collect ionized hydrogen gas from space for use as propellant by ramjet propulsion systems ( since much of the hydrogen is not ionized, some versions of a scoop propose ionizing the hydrogen, perhaps with a laser, ahead of the ship.
The collection-radius of such an ionic ramscoop is the distance from the ramjet at which the ramscoop's electric field is greater than the galactic electric field of 1. 6 × 10 < sup >− 19 </ sup > V / m, or the ramscoop's electromagnetic field is greater than the natural galactic magnetic field of 0. 1 nanotesla ( 1 × 10 < sup >− 6 </ sup > gauss ).
Another disadvantage of Bussard ramjet engine ( even with the most effective proton-proton chain ) is the speed limit for the ship equipped with ( maximum 0. 119 c = 35, 7 thousand km / s ).
The key condition that determines whether or not an interstellar ramjet will accelerate forward in the direction of its thrust is that the thrust of the ramjet must exceed drag that results from scooping up ions from space.
* d / dt ( mv < sub > 1 </ sub >) is the drag force experienced by the ramjet during its actual operation ; d / dt ( mv < sub > 1 </ sub >) is the mass of collected propellant per unit time times the velocity of the scooped ions relative to the ramjet starship.
* d / dt ( mv < sub > 2 </ sub >) is the thrust produced by the ramjet ; d / dt ( mv < sub > 2 </ sub >) is the mass of the collected ramjet propellant per unit time multiplied by the exhaust velocity at which it is expelled from the Ramjet engine to generate thrust.
ramjet and form
On 19 November 1996 Bayern-Chemie completed the latest in a series of tests designed to assess the attenuation of signals by the boron rich exhaust plume of the TDR, a concern highlighted by opponents of this form of ramjet propulsion.
ramjet and jet
Jet engines take a large volume of hot gas from a combustion process ( typically a gas turbine, but rocket forms of jet propulsion often use solid or liquid propellants, and ramjet forms also lack the gas turbine ) and feed it through a nozzle that accelerates the jet to high speed.
So long as the velocity of the ramjet engine exhaust jet is greater than the electric field-induced velocity of the incoming scooped ions there can be a net force in the direction of the ramjet's flight that will accelerate the spacecraft.
There are missiles in development, such as the MBDA Meteor, that “ breathe ” air ( using a ramjet, similar to a jet engine ) in order to extend their range.
Many jet engines, including rocket engines use a turbopump which is a centrifugal pump usually propelled by a gas turbine or in some cases a ram-air device ( particularly in ramjet engines which lack a shaft ).
A jet engine afterburner is an extended exhaust section containing extra fuel injectors, and since the jet engine upstream ( i. e., before the turbine ) will use little of the oxygen it ingests, the afterburner is, at its simplest, a type of ramjet.
The ATREX engine ( Air Turbo Ramjet Engine with eXpander cycle ) developed in Japan is an experimental precooled jet engine that works as a turbojet at low speeds and a ramjet up to mach 6. 0.
The scramjet had first been outlined at about the same time as the original LACES design in a NASA paper of 1958, and many companies were highly interested in seeing it develop, perhaps none more than Marquardt, whose ramjet business was dwindling with the introduction of newer jet engines and who had already started work on the scramjet.
ramjet and engine
A replacement for Blue Steel, the Mark 2, was planned with increased range and a ramjet engine, but was cancelled in 1960 to minimise delays to the Mk. 1.
* Jet engine ( including turbojet, turbofan, ramjet, Rocket, etc.
) An electric field can electrostatically attract the positive ions, and thus draw them inside a ramjet engine.
The scooped ions will however have an electric field-induced velocity when they are drawn inside of the ion ramjet engine.
On May 14, 1961, the world's first nuclear ramjet engine, " Tory-IIA ," mounted on a railroad car, roared to life for a few seconds.
Air-augmented rockets ( also known as rocket-ejector, ramrocket, ducted rocket, integral rocket / ramjets, or ejector ramjets ) use the supersonic exhaust of some kind of rocket engine to further compress air collected by ram effect during flight to use as additional working mass, leading to greater effective thrust for any given amount of fuel than either the rocket or a ramjet alone.
As it travels down the tube it is further compressed and mixed with the fuel-rich exhaust from the rocket engine, which heats the air much as a combustor would in a ramjet.
This design can even be slightly more efficient than a ramjet as the exhaust from the rocket engine compresses the air more than a ramjet normally would ; this raises the combustion efficiency as a longer, more efficient nozzle can be employed.
Another advantage is that the rocket works even at zero forward speed, whereas a ramjet requires forward motion to feed air into the engine.
Marquardt Corporation was one of the few aeronautical engineering firms that was dedicated almost solely to the development of the ramjet engine.
Meanwhile the main Van Nuys plant was also involved in research into new systems, including a nuclear-powered ramjet for Project Pluto and a liquid air cycle engine ( LACE ) for the Air Force's Aerospaceplane efforts.
* Bristol Thor, ramjet engine used on the Bristol Bloodhound missile
These proved very disappointing due to ramjet problems, which were traced to the use of a flare as an ignition source inside the engine.
II with a longer range ( around 75 miles ) achieved with improved ramjet engine and larger boosters.
This bypass ramjet system is designed to reduce the negative effects of drag resulting from air that passes into the intakes but doesn ’ t get fed into the main rocket engine, rather than generating appreciable thrust of their own.
ramjet and no
The slow pace of Russia's ramjet powered R-77 derivative, a mock-up of which had been displayed at the Paris Air Show but which had not progressed past component ground tests and for which the Russian air force had no requirement due to lack of funding, was offered as evidence that the full capability required by SR ( A ) 1239 would not be necessary for some time.
Scramjet ( supersonic combustion ramjet ) engines present a much different situation for the combustor than conventional gas turbine engines ( scramjets are not gas turbines, they generally have few or no moving parts ).
ramjet and major
Marquardt designs were developed through the 1940s into the 1960s, but the ramjet never became a major design and the company turned to other fields in the 1970s.
ramjet and can
The generated thrust can be calculated as the mass of ions expelled per second multiplied by the ramjet exhaust velocity ( V < sub > e </ sub >), adjusted for relativistic effects.
The " scoop " on the front of the ship sucks hydrogen from the currents in space and converts it into fuel like a Bussard ramjet and can, theoretically, keep going forever.
ramjet and be
Accordingly, an interstellar ramjet would have to be powered by other nuclear reactions, but the required isotopes are rare in the interstellar medium.
A fusion reactor used to power a ramjet starship might be a steady state magnetic fusion reactor based on the following nuclear fusion reactions.
The mass of the ion ram scoop must be minimized on an interstellar ramjet.
Heppenheimer analysed Bussard's original suggestion of fusing protons, but found the bremsstrahlung losses from compressing protons to fusion densities was greater than the power that could be produced by a factor of about 1 billion, thus indicating that the proposed version of the Bussard ramjet was infeasible.
They determined that their version of the ramjet would be unable to accelerate into the solar wind.
In the solar system, if the exhaust velocity of the ramjet exceeds 500 km / s there will be a net thrust that will accelerate the ramjet.
In order to reach ramjet speed, it would be launched from the ground by a cluster of conventional rocket boosters.
Many modern solid fueled ' ramjet ' powered missiles, such as the Mbda meteor, may in fact be air augmented rockets, and the distinction between a ramjet and an air augmented missile is rather blurred.
Many solid fueled ramjet missiles seem to be solid fueled ramrockets in all but name.
An RKV could theoretically be launched using any of the spacecraft propulsion techniques that are capable of accelerating starships to relativistic velocities, such as antimatter rockets, Bussard ramjet systems, or nuclear pulse propulsion ( see also relativistic rockets ).
Beta thus effectively functions as a ramjet in the lower atmosphere and thus must be launched using an electric launch track.
The idea was to combine the booster and ramjet into a single airframe, thereby reducing cost, size, and range safety requirements, as nothing would be jettisoned in flight.
Although his Eagles appear to be children, each of them, except for Dee, flies his own individual ramjet aircraft expertly, and are obviously much more savvy than their leader.
The HF-3 missile uses a rocket-ramjet propulsion system, with two side-by-side solid-propellant jettisonable strap-on rocket boosters for initial acceleration and a liquid-fueled ramjet ( believed to be using JP-10 fuel ) for sustained supersonic cruise.
Earlier speculation around the AMR-1 / LY-60 programme suggested that a ramjet engine was being developed for it, and such a powerplant would allow a missile to be effective at such long ranges.
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