|
LE-5
The LE-5 liquid rocket engine and its derivative models were developed in Japan to meet the need for an upper stage propulsion system for the H-I and H-II series of launch vehicles. It is a bipropellant design, using LH and LOX. Primary design and production work was carried out by Mitsubishi Heavy Industries. In terms of liquid rockets, it is a fairly small engine, both in size and thrust output, being in the 89 kN (20,000 lbf) and the more recent models the 130 kN (30,000 lbf) thrust class. The motor is capable of multiple restarts, due to a spark ignition system as opposed to the single use pyrotechnic or hypergolic igniters commonly used on some contemporary engines. Though rated for up to 16 starts and 40+ minutes of firing time, on the H-II the engine is considered expendable, being used for one flight and jettisoned. It is sometimes started only once for a nine-minute burn, but in missions to GTO the engine is often fired a second time to inject the pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LE-5
The LE-5 liquid rocket engine and its derivative models were developed in Japan to meet the need for an upper stage propulsion system for the H-I and H-II series of launch vehicles. It is a bipropellant design, using LH and LOX. Primary design and production work was carried out by Mitsubishi Heavy Industries. In terms of liquid rockets, it is a fairly small engine, both in size and thrust output, being in the 89 kN (20,000 lbf) and the more recent models the 130 kN (30,000 lbf) thrust class. The motor is capable of multiple restarts, due to a spark ignition system as opposed to the single use pyrotechnic or hypergolic igniters commonly used on some contemporary engines. Though rated for up to 16 starts and 40+ minutes of firing time, on the H-II the engine is considered expendable, being used for one flight and jettisoned. It is sometimes started only once for a nine-minute burn, but in missions to GTO the engine is often fired a second time to inject the pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
H3 (rocket)
The H3 Launch Vehicle is an expendable launch system in development in Japan. H3 launch vehicles are liquid-propellant rockets with strap-on solid rocket boosters and are planned to be launched from Tanegashima Space Center in Japan. Mitsubishi Heavy Industries (MHI) and JAXA are responsible for the design, manufacture, and operation of the H3. The H3 is the world's first rocket to use an expander bleed cycle for the first stage engine. , the minimum configuration is to carry a payload of up to into Sun-synchronous orbit (SSO) for about 5 billion yen, and the maximum configuration is to carry more than into geostationary transfer orbit (GTO). The H3-24 variant will deliver more than of payload to lunar transfer orbit (TLI) and of payload to geostationary transfer orbit (GTO)(∆Ｖ=1830 m/s). , the first H3 is planned to be launched in 2023 or later. Development The development of the H3 was authorized by the Japanese government on 17 May 2013. The H3 Launch Vehi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expander Cycle (rocket)
The expander cycle is a power cycle of a bipropellant rocket engine. In this cycle, the fuel is used to cool the engine's combustion chamber, picking up heat and changing phase. The now heated and gaseous fuel then powers the turbine that drives the engine's fuel and oxidizer pumps before being injected into the combustion chamber and burned. Because of the necessary phase change, the expander cycle is thrust limited by the square–cube law. When a bell-shaped nozzle is scaled, the nozzle surface area with which to heat the fuel increases as the square of the radius, but the volume of fuel to be heated increases as the cube of the radius. Thus beyond approximately 300 kN (70,000 lbf) of thrust, there is no longer enough nozzle area to heat enough fuel to drive the turbines and hence the fuel pumps. Higher thrust levels can be achieved using a bypass expander cycle where a portion of the fuel bypasses the turbine and or thrust chamber cooling passages and goes directly to the ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LE-9
The LE-9 is a liquid cryogenic rocket engine burning liquid hydrogen and liquid oxygen in an expander bleed cycle. Two or three will be used to power the core stage of the H3 launch vehicle. The newly developed LE-9 engine is the most important factor in achieving cost reduction, improved safety and increased thrust. The expander bleed cycle used in the LE-9 engine is a highly reliable combustion method that Japan has put into practical use for the LE-5A/ B engine. However, it is physically difficult for an expander bleed cycle engine to generate large thrust, so the development of the LE-9 engine with a thrust of is the most challenging and important development element. Firing tests of the LE-9 first-stage engine began in April 2017. On 21 January 2022, the launch of the first H3 was rescheduled to FY 2022 or later, citing technical problems regarding the first stage LE-9 engine. See also * H3 Launch Vehicle * LE-7 * LE-5 The LE-5 liquid rocket engine and its derivati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
H-IIB
H-IIB (H2B) was an expendable space launch system jointly developed by the Japanese government's space agency JAXA and Mitsubishi Heavy Industries. It was used to launch the H-II Transfer Vehicle (HTV, or ''Kōnotori'') cargo spacecraft for the International Space Station. The H-IIB was a liquid-fueled rocket, with solid-fuel strap-on boosters and was launched from the Tanegashima Space Center in southern Japan. H-IIB made its first flight in 2009, and had made a total of nine flights through 2020 with no failures. H-IIB was able to carry a payload of up to to Geostationary transfer orbit (GTO), compared with the payload of 4000-6000 kg for the H-IIA, a predecessor design. Its performance to low Earth orbit (LEO) was sufficient for the H-II Transfer Vehicle (HTV). The first H-IIB was launched in September 2009 and the last H-IIB was launched in May 2020. Development The H-IIB was a space launch vehicle jointly designed, manufactured and operated by JAXA and Mitsub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LE-7
The LE-7 and its succeeding upgrade model the LE-7A are staged combustion cycle LH/LOX liquid rocket engines produced in Japan for the H-II series of launch vehicles. Design and production work was all done domestically in Japan, the first major ( main/first-stage) liquid rocket engine with that claim, in a collaborative effort from the National Space Development Agency (NASDA), Aerospace Engineering Laboratory (NAL), Mitsubishi Heavy Industries, and Ishikawajima-Harima. NASDA and NAL have since been integrated into JAXA. However, a large part of the work was contracted to Mitsubishi, with Ishikawajima-Harima providing turbomachinery, and the engine is often referred to as the Mitsubishi LE-7(A). The original LE-7 was an expendable, high efficiency, medium-sized motor with sufficient thrust for use on the H-II. H-II Flight 8, only operational LE-7 failure The fuel turbopump had an issue using the originally designed inducer (a propeller-like axial pump used to raise the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
H-IIA
H-IIA (H-2A) is an active expendable launch system operated by Mitsubishi Heavy Industries (MHI) for the Japan Aerospace Exploration Agency. These liquid fuel rockets have been used to launch satellites into geostationary orbit; lunar orbiting spacecraft; '' Akatsuki'', which studied the planet Venus; and the Emirates Mars Mission, which was launched to Mars in July 2020. Launches occur at the Tanegashima Space Center. The H-IIA first flew in 2001. , H-IIA rockets were launched 45 times, including 39 consecutive missions without a failure, dating back to 29 November 2003. Production and management of the H-IIA shifted from JAXA to MHI on 1 April 2007. Flight 13, which launched the lunar orbiter SELENE, was the first H-IIA launched after this privatization. The H-IIA is a derivative of the earlier H-II rocket, substantially redesigned to improve reliability and minimize costs. There have been four variants, with two in active service (as of 2020) for various purposes. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Rocket
A liquid-propellant rocket or liquid rocket utilizes a rocket engine that uses liquid propellants. Liquids are desirable because they have a reasonably high density and high specific impulse (''I''sp). This allows the volume of the propellant tanks to be relatively low. It is also possible to use lightweight centrifugal turbopumps to pump the rocket propellant from the tanks into the combustion chamber, which means that the propellants can be kept under low pressure. This permits the use of low-mass propellant tanks that do not need to resist the high pressures needed to store significant amounts of gasses, resulting in a low mass ratio for the rocket. An inert gas stored in a tank at a high pressure is sometimes used instead of pumps in simpler small engines to force the propellants into the combustion chamber. These engines may have a higher mass ratio, but are usually more reliable, and are therefore used widely in satellites for orbit maintenance. Liquid rockets can be monop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocket Engines Of Japan
A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely from propellant carried within the vehicle; therefore a rocket can fly in the vacuum of space. Rockets work more efficiently in a vacuum and incur a loss of thrust due to the opposing pressure of the atmosphere. Multistage rockets are capable of attaining escape velocity from Earth and therefore can achieve unlimited maximum altitude. Compared with airbreathing engines, rockets are lightweight and powerful and capable of generating large accelerations. To control their flight, rockets rely on momentum, airfoils, auxiliary reaction engines, gimballed thrust, momentum wheels, deflection of the exhaust stream, propellant flow, spin, or gravity. Rockets for military and recreational uses date back to at least 13th-century China. Significant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Impulse
Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine (a rocket using propellant or a jet engine using fuel) creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse is exactly proportional to the effective exhaust gas velocity. A propulsion system with a higher specific impulse uses the mass of the propellant more efficiently. In the case of a rocket, this means less propellant needed for a given delta-v, so that the vehicle attached to the engine can more efficiently gain altitude and velocity. In an atmospheric context, specific impulse can include the contribution to impulse provided by the mass of external air that is accelerated by the engine in some way, such as by an internal turbofan or heating by fuel combustion participation then thrust expansion or by external propeller. Jet engines breathe external air for both combustion and by-pass, and therefore have a much higher specific impulse than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
