Scramjet is a variant of the Ramjet airbreathing jet engine where combustion takes place in supersonic air flow. Serpenti on ramjets, scramjets that depend on high-speed vehicles to force compresses and reduce the speed of the air that enters before combustion (hence ram jets), but while ramjets decrease airspeed to subsonic speeds before combustion, the air flow on the scramjet is supersonic flow throughout the engine. This allows the scramjet to operate efficiently at very high speeds: theoretical projections place the highest speed of the scramjet between Mach 12 (9,100 mph, 15,000 km / h) and Mach 24 (18,000 mph, 29,000 km / h).
A scramjet engine is a type of jet engine, and relies on burning fuel and oxidizing compounds to produce thrust. Similar to conventional jet engines, aircraft-powered scramjets carry fuel on the aircraft, and are obtained by oxidants by atmospheric oxygen consumption (compared to rockets, which carry both fuel and oxidizing agents). This requirement limits scramjets to suborbital flight of the atmosphere, where the oxygen content of the air is sufficient to sustain combustion.
Scramjet engine is designed to be a hypersonic or high speed aircraft driver above 5 mach. Previously, for hypersonic-powered aircraft a rocket type engine was used. Unlike a rocket engine, a scramjet engined airplane does not need to carry oxygen as a fuel burner because oxygen is taken from free air. With no need to carry oxygen, the flight load will be lighter. This allows the aircraft to move faster or have more room to carry space.
Scramjet engine is a development of the type of ramjet engine (ram-air compression). Both types of engines are different from conventional jet engines, turboprops, or turbojets. In a turbojet engine, air enters the combustion chamber after passing through the engine compressor to increase the pressure. Not so with scramjet and ramjet machines. In both types of engine the outside air for combustion of fuel enters the combustion chamber without being compressed. There are no rotating engine components on the scramjet or ramjet engines. Air pressure is free to enter the combustion chamber of the scramjet or ramjet engine solely because of the speed of the aircraft. Herein lies the difference between ramjet and scramjet machines.
On ramjet, air enters the combustion chamber at subsonic speed or below the speed of sound. Whereas on Scramjet, air enters the combustion chamber at supersonic speeds. The faster air flow velocity on the scramjet makes the oxygen supply to the scramjet engine more intensive, so the energy produced is greater and allows the aircraft to move up to hypersonic speeds.
The advantages of an aircraft using a scramjet engine are as follows:
1. No need to carry oxygen
planes that already use this scram jet engine don’t need to carry oxygen
the aircraft becomes lighter
2. No rotating parts make it easier to produce
if an airplane that uses a turbojet engine, turbofan etc. uses a turbine to generate
thrust with a plane that uses a scramjet engine is no longer using a turbine
to produce thrust power makes the aircraft lighter and more efficient
3. Have a specific higher push
Scramjet planes have a higher thrust (change in momentum per propellant unit) than at
conventional engines, can provide between 1000 and 4000 seconds, while rockets only provide
600 seconds or less
4. Higher speed can mean cheap access to space in the future
this scramjet plane has a higher speed than a rocket making this scramjet plane more
easy to fly into space and certainly cheaper & more efficient.
Scramjet will fly at 10 times the speed of sound. Compared to the American Raptor, the most sophisticated aircraft today, the maximum speed is 2 times the speed of sound.
For example: If we are living in New York and want to go to Tokyo take a long time, which is 18 hours (1080 minutes), if taken by using a Scramjet plane, the time taken is only 120 minutes or equal to 2 hours, it is really a time saving very efficient.
Technology does aim to increase the ease of human life, but that does not mean we are very dependent on the technology. Even to be a necessity and will plunge human beings into unproductive because it is too dependent on the name of technology. Therefore, it must be based on strong thinking so that in the future it does not harm humans themselves.
During World War II, a significant amount of time and effort was put into research into high-speed jet aircraft and rockets, which were dominated by Germany. After the war, the US and Britain engaged several German scientists and military technology through Operation Paperclip to begin to put more emphasis on developing their own weapons, including jet engines. Bell X-1 achieved supersonic flights in 1947 and in the early 1960s, rapid progress toward faster aircraft suggested that operational aircraft would fly at “hypersonic” speeds within a few years. Except for special rocket research vehicles such as the North American X-15 and other rocket-powered spacecraft, aircraft with top speeds remain parallel, generally in the range of Mach 1 to Mach 3. In the 1950s and 1960s various experimental scramjet machines were built and tested in the US and UK. In 1958, an analytical paper discussed the benefits and disadvantages of supersonic herbs. In 1964, Drs. Frederick S. Billig and Gordon L. Dugger filed a patent application for supersonic burning ramjet based on Billig’s Ph.D. thesis. This patent was issued in 1981 after the issuance of a confidentiality order. In 1981 tests were carried out in Australia under the guidance of Professor Ray Stalker at the T3 soil test facility at ANU.
The first Scramjet flight test was conducted by the Soviet Union in 1991. This is a dual axisymmetric fuel mode scramjet developed by the Central Institute of Aviation Motors (CIAM), Moscow in the late 1970s. Scramjet flies forcefully over SA-5 land-to-air missiles that include an experimental support unit known as the “Hypersonic Flying Laboratory” (HFL), “Kholod”.
Progress in the 2000s
In the 2000s, significant progress was made in developing hypersonic technology, especially in the field of scramjet machines. The HyShot project demonstrated scramjet combustion on July 30, 2002. The scramjet engine worked effectively and demonstrated supersonic combustion in action. However, the engine was not designed to give impetus to move a craft. It was designed more or less as a technology demonstrator. The joint British and Australian teams from the British defense company QinetiQ and the University of Queensland were the first group to show skramjets working in atmospheric tests.
The US effort is probably the best funded, and the Hyper-X team claims the first flight of a scramjet powered vehicle with thrust with a full surface aerodynamic maneuver in 2004 with the X-43A. On June 15, 2007, the US Defense Research and Development Agency (DARPA), in collaboration with the Australian Defense Science and Technology Organization (DSTO), announced a successful scramjet flight on Mach 10 using rocket engines to raise test vehicles to hypersonic speeds. A series of scramjet soil tests were completed at the Langley Arc-Heated Scramjet (AHSTF) Scramjet Test Facility on simulated Mach 8 flight conditions. This trial is used to support HIFiRE 2 flights.
On May 22, 2009, Woomera hosted the first successful hypersonic flight test flight at HIFiRE. The launch is one of ten planned flight trials. The flight series is part of a joint research program between the Defense Science and Technology Organization and the US Air Force, which is designated as the International Hypersonic Aviation Experimental Experiment (HIFiRE). HIFiRE is investigating hypersonic technology (the study of flight exceeds five times the speed of sound) and its application in launching scramjet-scale launch vehicles, the aim of which is to support the new Boeing X-51 scamjet demonstrators while also building a strong base. flight test data for the development of the rapid reaction chamber launch and hypersonic “quick strike” weapons.
Progress in the 2010s
On 22 and 23 March 2010, Australian and American defense scientists successfully tested hypersonic rockets (HIFiRE). The aircraft reached an atmospheric speed “more than 5,000 kilometers per hour” (Mach 4) after taking off from the Woomera Test Range in the interior of South Australia. On May 27, 2010, NASA and the United States Air Force successfully flew the X-51A Waverider for approximately 200 seconds on Mach 5, setting a new world record for flight duration with hypersonic airspeed. Waverider flies independently before losing acceleration due to unknown reasons and destroys himself according to plan.
The test was declared successful. The X-51A was carried on a B-52, accelerated to Mach 4.5 through a solid rocket booster, and then turned on the Pratt & Whitney Rocketdyne scramjet engine to reach Mach 5 at a price of 70,000 feet. However, the second flight on June 13, 2011 ended prematurely when the engine ignited briefly on ethylene but failed to switch to its main JP-7 fuel, failing to reach full power.
How a Scramjet Machine Works
Scramjet will fly at 10 times the speed of sound. Compared to the American Raptor, the most sophisticated aircraft today, the maximum speed is 2 times the speed of sound. For example: If we are living in New York and want to go to Tokyo take a long time, which is 18 hours (1080 minutes), if taken by using a Scramjet plane, the time taken is only 120 minutes or equal to 2 hours, it is really a time saving very efficient.
Technology does aim to increase the ease of human life, but that does not mean we become very dependent on the technology even to become a habbit and will plunge human beings into productive armpit because it is too dependent on the so-called instant devices. Actually the benefits of technology is to improve the level and quality of human civilization on earth to a better level. Therefore, it must be based on strong thinking so that in the future it does not harm humans themselves.