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Dual Pulse Rocket Motor
A pulsed rocket motor is typically defined as a multiple-pulse solid-fuel rocket motor. This design overcomes difficulties shutting down and reigniting solid propellant motors. The pulse rocket motor allows the motor to be burned in segments (or pulses) that burn until completion of that segment. The next segment can be ignited on command by either an onboard algorithm or in a pre-planned sequence. All of the segments are contained in a single rocket motor case, as opposed to staged rocket motors. The pulsed rocket motor is made by pouring each segment of propellant separately. Between each segment is a barrier that prevents the other segments from burning until ignited. At ignition of a second pulse, the burning of the propellant generally destroys the barrier. The benefit of the pulsed rocket motor is that, by the on-command ignition of the subsequent pulses, near-optimal energy management of the propellant burn can be accomplished. Each pulse can have a different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulse (physics)
In physics, a pulse is a generic term describing a single disturbance that moves through a transmission medium. This medium may be vacuum (in the case of electromagnetic radiation) or matter, and may be indefinitely large or finite. Pulse reflection Consider a pulse moving through a medium - perhaps through a rope or a slinky. When the pulse reaches the end of that medium, what happens to it depends on whether the medium is fixed in space or free to move at its end. For example, if the pulse is moving through a rope and the end of the rope is held firmly by a person, then it is said that the pulse is approaching a fixed end. On the other hand, if the end of the rope is fixed to a stick such that it is free to move up or down along the stick when the pulse reaches its end, then it is said that the pulse is approaching a free end. Free end A pulse will reflect off a free end and return with the same direction of displacement that it had before reflection. That is, a pulse with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocket Engine Nozzle
A rocket engine nozzle is a propelling nozzle (usually of the de Laval type) used in a rocket engine to expand and accelerate combustion products to high supersonic velocities. Simply: propellants pressurized by either pumps or high pressure ullage gas to anywhere between two and several hundred atmospheres are injected into a combustion chamber to burn, and the combustion chamber leads into a nozzle which converts the energy contained in high pressure, high temperature combustion products into kinetic energy by accelerating the gas to high velocity and near-ambient pressure. History Simple bell-shaped nozzles were developed in the 1500s. The de Laval nozzle was originally developed in the 19th century by Gustaf de Laval for use in steam turbines. It was first used in an early rocket engine developed by Robert Goddard, one of the fathers of modern rocketry. It has since been used in almost all rocket engines, including Walter Thiel's implementation, which made possible G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Pulse Propulsion
Nuclear pulse propulsion or external pulsed plasma propulsion is a hypothetical method of spacecraft propulsion that uses nuclear explosions for thrust. It originated as Project ''Orion'' with support from DARPA, after a suggestion by Stanislaw Ulam in 1947. Newer designs using inertial confinement fusion have been the baseline for most later designs, including Project ''Daedalus'' and Project ''Longshot''. History Los Alamos Calculations for a potential use of this technology were made at the laboratory from and toward the close of the 1940s to the mid-1950s. Project Orion Project Orion was the first serious attempt to design a nuclear pulse rocket. A design was formed at General Atomics during the late 1950s and early 1960s, with the idea of reacting small directional nuclear explosives utilizing a variant of the Teller–Ulam two-stage bomb design against a large steel pusher plate attached to the spacecraft with shock absorbers. Efficient directional explosives maxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomized Fuel
Atomization refers to breaking bonds in some substance to obtain its constituent atoms in gas phase. By extension, it also means separating something into fine particles, for example: process of breaking bulk liquids into small droplets. Atomization may also refer to: Science and technology * The making of an aerosol, which is a colloidal suspension of fine solid particles or liquid droplets in a gas * An apparatus using an atomizer nozzle * Sprays, mists, fogs, clouds, dust clouds and smoke, which appear to be atomized * A nebulizer, which is a device used to administer medication in the form of a mist inhaled into the lungs * An electronic cigarette atomiser is a component which employs a heating element to vaporize a flavored solution, that may or may not contain nicotine, for inhalation into the lungs * The conversion of a vaporized sample into atomic components in atomic spectroscopy Sociology * Atomization is frequently used as a synonym for social alienation. The arts * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jet Engine
A jet engine is a type of reaction engine, discharging a fast-moving jet (fluid), jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition may include Rocket engine, rocket, Pump-jet, water jet, and hybrid propulsion, the term typically refers to an internal combustion airbreathing jet engine, air-breathing jet engine such as a turbojet, turbofan, ramjet, pulse jet engine, pulse jet, or scramjet. In general, jet engines are internal combustion engines. Air-breathing jet engines typically feature a Axial compressor, rotating air compressor powered by a turbine, with the leftover power providing thrust through the propelling nozzle—this process is known as the Brayton cycle, Brayton thermodynamic cycle. Jet aircraft use such engines for long-distance travel. Early jet aircraft used turbojet engines that were relatively inefficient for subsonic flight. Most modern subsonic jet aircraft use more complex High-bypass turbofan, high-bypas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulse Jet Engine
In medicine, the pulse refers to the rhythmic pulsations (expansion and contraction) of an artery in response to the cardiac cycle (heartbeat). The pulse may be felt (palpated) in any place that allows an artery to be compressed near the surface of the body close to the skin, such as at the neck (carotid artery), wrist (radial artery or ulnar artery), at the groin (femoral artery), behind the knee (popliteal artery), near the ankle joint (posterior tibial artery), and on foot (dorsalis pedis artery). The pulse is most commonly measured at the wrist or neck for adults and at the brachial artery (inner upper arm between the shoulder and elbow) for infants and very young children. A sphygmograph is an instrument for measuring the pulse. Physiology Claudius Galen was perhaps the first physiologist to describe the pulse. The pulse is an expedient Touch, tactile method of determination of Systole (medicine), systolic blood pressure to a trained observer. Diastolic blood pressure i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Generator
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. The term often refers to a device that uses a rocket propellant to generate large quantities of gas. The gas is typically used to drive a turbine rather than to provide thrust as in a rocket engine. Gas generators of this type are used to power turbopumps in rocket engines, in a gas-generator cycle. It is also used by some auxiliary power units to power electric generators and hydraulic pumps. Another common use of the term is in the industrial gases industry, where gas generators are used to produce gaseous chemicals for sale. For example, the chemical oxygen generator, which delivers breathable oxygen at a controlled rate over a prolonged period. During World War II, portable gas generators that converted Coke (fuel), coke to producer gas were used to power vehicles as a way o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinetic Kill Vehicle
A kinetic energy weapon (also known as kinetic weapon, kinetic energy warhead, kinetic warhead, kinetic projectile, kinetic kill vehicle) is a projectile weapon based solely on a projectile's kinetic energy to inflict damage to a target, instead of using any explosive, incendiary, chemical or radiological payload. All kinetic weapons work by attaining a high flight speedgenerally supersonic or even up to hypervelocityand collide with their targets, converting their kinetic energy and relative impulse into destructive shock waves, heat and cavitation. In kinetic weapons with unpowered flight, the muzzle velocity or launch velocity often determines the effective range and potential damage of the kinetic projectile. Kinetic weapons are the oldest and most common ranged weapons used in human history, with the projectiles varying from blunt projectiles such as rocks and round shots, pointed missiles such as arrows, bolts, darts, and javelins, to modern tapered high-velocity i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SM-3
The RIM-161 Standard Missile 3 (SM-3) is a ship-based surface-to-air missile used by the United States Navy to intercept ballistic missiles as a part of Aegis Ballistic Missile Defense System. Although primarily designed as an anti-ballistic missile, the SM-3 has also been employed in an anti-satellite capacity against a satellite at the lower end of low Earth orbit.Pentagon news briefing of February 14, 2008video : although no name for the satellite is given, the launch date of December 14, 2006 is stated The SM-3 is primarily used and tested by the and also operated by the |
PL-15
The PL-15 ( zh, s=霹雳-15, p=Pī Lì-Yāo Wǔ, l=Thunderbolt-15, NATO reporting name: CH-AA-10 Abaddon) is an active radar homing, active radar-guided long-range beyond-visual-range air-to-air missile developed by the People's Republic of China, used by the People's Liberation Army Air Force (PLAAF) and People's Liberation Army Naval Air Force, Naval Air Force (PLANAF), and the Pakistan Air Force. It can reach speeds of up to Mach 5 (speed), Mach 5 and has a maximum range of about 300 km, though the PL-15E export version that is sold to Pakistan is reported to have a reduced range of about 145 km. It is the primary beyond-visual-range air-to-air missile carried by PLA fixed-wing combat aircraft. Its within-visual-range counterpart is the PL-10. Development The PL-15 is developed by Luoyang-based China Airborne Missile Academy (CAMA). The missile was test fired in 2011 and referenced by Chinese state media in 2015. It was spotted in 2013 mounted on a prototype of C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burn Time
A burn is an injury to skin, or other tissues, caused by heat, electricity, chemicals, friction, or ionizing radiation (such as sunburn, caused by ultraviolet radiation). Most burns are due to heat from hot fluids (called scalding), solids, or fire. Burns occur mainly in the home or the workplace. In the home, risks are associated with domestic kitchens, including stoves, flames, and hot liquids. In the workplace, risks are associated with fire and chemical and electric burns. Alcoholism and smoking are other risk factors. Burns can also occur as a result of self-harm or violence between people (assault). Burns that affect only the superficial skin layers are known as superficial or first-degree burns. They appear red without blisters, and pain typically lasts around three days. When the injury extends into some of the underlying skin layer, it is a partial-thickness or second-degree burn. Blisters are frequently present and they are often very painful. Healing can requir ... [...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 Rocket propellant#Solid chemical propellants, solid propellants (fuel/oxidizer). The earliest rockets were solid-fuel rockets powered by gunpowder. The inception of gunpowder rockets in warfare can be credited to the ancient Chinese, and in the 13th century, the Mongols played a pivotal role in facilitating their westward adoption. All rockets used some form of solid or powdered propellant until the 20th century, when liquid-propellant rockets offered more efficient and controllable alternatives. Because of their simplicity and reliability, solid rockets are still used today in military armaments worldwide, model rockets, solid rocket boosters and on larger applications. Since solid-fuel rockets can remain in storage for an extended period without much propellant degradation, and since they almost always launch reliably, they have been frequently used in military applications such as missiles. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
