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Excess Thrust
Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that system. The force applied on a surface in a direction perpendicular or normal to the surface is also called thrust. Force, and thus thrust, is measured using the International System of Units (SI) in newtons (symbol: N), and represents the amount needed to accelerate 1 kilogram of mass at the rate of 1 meter per second per second. In mechanical engineering, force orthogonal to the main load (such as in parallel helical gears) is referred to as static thrust. Examples A fixed-wing aircraft propulsion system generates forward thrust when air is pushed in the direction opposite to flight. This can be done by different means such as the spinning blades of a propeller, the propelling jet of a jet engine, or by ejecting hot gases from a rocket e ... [...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] |
Jet Engine
A jet engine is a type of reaction engine discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include rocket, Pump-jet, water jet, and hybrid propulsion, the term typically refers to an internal combustion airbreathing jet engine such as a turbojet, turbofan, ramjet, or pulse jet engine, pulse jet. In general, jet engines are internal combustion engines. Airbreathing 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-bypass turbofan engines. They give higher speed and greater fuel eff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meganewton
The newton (symbol: N) is the unit of force in the International System of Units (SI). It is defined as 1 kg⋅m/s, the force which gives a mass of 1 kilogram an acceleration of 1 metre per second per second. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion. Definition A newton is defined as 1 kg⋅m/s (it is a derived unit which is defined in terms of the SI base units). One newton is therefore the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in the direction of the applied force. The units "metre per second squared" can be understood as measuring a rate of change in velocity per unit of time, i.e. an increase in velocity by 1 metre per second every second. In 1946, Conférence Générale des Poids et Mesures (CGPM) Resolution 2 standardized the unit of force in the MKS system of units to be the amount needed to accelerate 1 kilogram of mass at the rate of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Shuttle Main Engine
The Aerojet Rocketdyne RS-25, also known as the Space Shuttle Main Engine (SSME), is a liquid-fuel cryogenic rocket engine that was used on NASA's Space Shuttle and is currently used on the Space Launch System (SLS). Designed and manufactured in the United States by Rocketdyne (later Pratt & Whitney Rocketdyne and Aerojet Rocketdyne), the RS-25 burns cryogenic liquid hydrogen and liquid oxygen propellants, with each engine producing thrust at liftoff. Although RS-25 heritage traces back to the 1960s, its concerted development began in the 1970s with the first flight, STS-1, on April 12, 1981. The RS-25 has undergone upgrades over its operational history to improve the engine's reliability, safety, and maintenance load. The engine produces a specific impulse (''I''sp) of in a vacuum, or at sea level, has a mass of approximately , and is capable of throttling between 67% and 109% of its rated power level in one-percent increments. Components of the RS-25 operate at tempera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
