Vocabulary Word
Word: propellant
Definition: (propellent) substance which propels or drives forward (such as an explosive charge or a rocket fuel)
Definition: (propellent) substance which propels or drives forward (such as an explosive charge or a rocket fuel)
Sentences Containing 'propellant'
As a result the H-IIB first stage holds 70% more propellant than that of the H-IIA.
The rocket engine uses a combination of high test peroxide and kerosene; the propellant tanks contain about 1500 kg of hydrogen peroxide and 500 kg of kerosene.
The accident had significant long-term consequences, however, as it exposed the volatility of German propellant charges.
The Germans therefore reworked the composition of the propellant, which was in service by 1914.
Electric matches can be used in any application where source of heat is needed at a precisely controlled point in time, typically to ignite a propellant or explosive.
It is a separate-loading projectile - propellant bags or MAC charges are loaded separately.
The M114 howitzer can fire an M107 up to 14.5 km using M4A2 "White Bag" propellant; maximum range is 18.1 km.
Measures to reduce the expenditure were evaluated and based on the analysis, enough propellant could be saved to complete the planned 9-day plus science mission.
For this reason, the mono-metal bullets similar to the Barnes TSX may have to be seated more deeply into the case displacing volume which could be filled with the propellant.
A lightning rocket can have solid propellant that has cesium salts added which produces a conductive path when the exhaust gases are discharged from the rocket that is expelled to the static layer of a thundercloud.
The main engines were shut down before complete depletion of propellant, as running dry would have destroyed the engines.
Chemical rockets are the most common type of high performance rocket and they typically create their exhaust by the combustion of rocket propellant.
In guns internal ballistics covers the time from the propellant's ignition until the projectile exits the gun barrel.
These guns fired a projectile using cordite MD propellant.
There may be a single propellant, or multiple propellants; in the latter case one can distinguish fuel and oxidizer.
A potential other method is that the propellant is not burned but just heated.
The mass ratio is just a way to express what proportion of the rocket is propellant (fuel/oxidizer combination) prior to engine ignition.
Typically, a single-stage rocket might have a mass fraction of 90% propellant, 10% structure, and hence a mass ratio of 10:1 . The impulse delivered by the motor to the rocket vehicle per weight of fuel consumed is often reported as the rocket propellant's "specific impulse".
A propellant with a higher specific impulse is said to be more efficient because more thrust is produced while consuming a given amount of propellant.
Hybrid solid/liquid bi-propellant rocket engines are starting to see limited use as well.
Often, the ingredients of a double-base propellant have multiple roles such as RDX which is both a fuel and oxidizer or nitrocellulose which is a fuel, oxidizer, and plasticizer.
During the 1950s and 60s researchers in the United States developed Ammonium Perchlorate Composite Propellant (APCP).
A comparison of the highest specific impulses achieved with the various solid and liquid propellant combinations used in current launch vehicles is given in the article on solid-fuel rockets.
Solid propellant rockets are much easier to store and handle than liquid propellant rockets.
High propellant density makes for compact size as well.
These features plus simplicity and low cost make solid propellant rockets ideal for military applications.
The propellant mass ratios of solid propellant upper stages is usually in the .91 to .93 range which is as good as or better than that of most liquid propellant upper stages but overall performance is less than for liquid stages because of the solids' lower exhaust velocities.
A drawback to solid rockets is that they cannot be throttled in real time, although a programmed thrust schedule can be created by adjusting the interior propellant geometry.
Casting large amounts of propellant requires consistency and repeatability which is assured by computer control.
Casting voids in propellant can adversely affect burn rate so the blending and casting takes place under vacuum and the propellant blend is spread thin and scanned to assure no large gas bubbles are introduced into the motor.
Only the combustion chamber of a liquid-fueled rocket needs to withstand high combustion pressures and temperatures and they can be regeneratively cooled by the liquid propellant.
On vehicles employing turbopumps, the propellant tanks are at very much less pressure than the combustion chamber.
While liquid propellants are cheaper than solid propellants, for orbital launchers, the cost savings do not, and historically have not mattered; the cost of the propellant is a very small portion of the overall cost of the rocket.
A gas propellant usually involves some sort of compressed gas.
The mixing is not a well-controlled process and generally quite a lot of propellant is left unburned, which limits the efficiency of the motor.
There has recently been an increase in hybrid motor development for nonmilitary suborbital work:
Gel propellant.
Some work has been done on gelling liquid propellants to give a propellant with low vapor pressure to reduce the risk of an accidental fireball.
Gelled propellant behaves like a solid propellant in storage and like a liquid propellant in use.
Indeed, some dense hydrocarbon/LOX propellant combinations have higher performance when the dry mass penalties are included.
Due to lower "I"sp, dense propellant launch vehicles have a higher takeoff mass, but this does not mean a proportionately high cost; on the contrary, the vehicle may well end up cheaper.
Troposphere 5 is a two stage solid-propellant rocket with a thrust of 7 tons, launched on March 29, 2009.
Improvements made from the Delta III stage to the Delta IV stage include the use of friction stir welding and increased propellant tank dimensions.
Because of this the gun could be fired using three different sized propellant charges, a light, medium and heavy charge.
It can also transfer propellant from "Zvezda" and "Zarya" to the propulsion system of docked vehicles—Soyuz and Progress.
In some other designs, the propellant charge burns completely within the tube.
All necessary propellant and consumables were to be brought from Earth in von Braun's proposal. Some crew remained in the passenger ships during the mission for orbit-based observation of Mars and to maintain the ships.
However even if such a ship stocked full of goods could be put together in orbit, it would need an additional (large) supply of propellant to send it to Mars.
When we think of getting astronauts to the surface of Mars and back home we quickly realize that an enormous amount of propellant is needed if everything is taken from the Earth.
Another technique to reduce Earth-brought propellant requirements is aerobraking.
This is a form of rocket propulsion by virtue of Newton's third law with the asteroid's mass as the propellant.