The SCRAMJET, simply abbreviated from Supersonic Combustion Ramjet, is the latest evolution of the jet engine family. NASA made the news with each test of the X-43A scramjet craft, so I set about to discover why this type of jet engine should garner so much scientific attention.
Turbojet
The most basic jet engine is the turbojet. As soon as the air enters the front of the engine, the blades of the compressor, compresses the air before funneling it into the combustion chamber. During the compression, not only is the density of the air increased by compressing it in a confined chamber, but the temperature of the air also increases as the air molecules of squeezed closer together.
The resulting air that emerges into the combustion chamber is thereby preheated, and the amount of oxygen per volume is increased to facilitate combustion. This becomes an important factor at increased altitudes, where the air density (and thus also oxygen density) decreases. In the combustion chamber, fuel mixes with the air before being ignited.
As the air-fuel mixture is burned, the gases expand so that the pressure is increased further. Part of this energy is captured by the turbine blades and translated into the rotation of the compressor shaft, and thereby supplying the energy the compressor needs to function.
The rest of the hot gases are forced through the necked-down exhaust nozzle, thus accelerating them further. The force of the hot gases expelled in the exhaust, provides all of the planes thrust.
Turbofan
This a modified turbojet engine in which part of the air compressed in the compressor completely bypasses inner engine core housing the combustion chamber and turbine. Since the bypassed air is compressed and...
... middle of paper ...
...e the use of scramjets in missiles and satellite rockets is much more realistic than in aircraft. A missile can be fairly easily accelerated by a gun system, but it would be highly difficult to accelerate an aircraft to hypersonic speeds so that the scramjet can take over. Even if a way could be found to accelerate an aircraft, the design shape necessary to handle hypersonic speeds is not suited for subsonic speeds necessary for landings. The craft could be slowed by a system of parachutes, but seems highly uneconomical and impractical for a craft subject to regular use. The other alternative is the development of a hybrid engine that could be switched between subsonic jet operation, to ramjet, and finally scramjet configurations. In the future this may become a viable possibility, but first it will require years of research and testing of scramjet behavior.
...Another way to decrease the disturbance over the wings are to move the wings lower than the horizontal stabilizer or visa versa to allow the shock waves moving over each wing to miss each other. Most aircraft today do not have enough fuel to maintain the speed of sound for great distances. Engineers have designed a brand new aircraft known as the F-22, which has the ability to fly an entire mission at supersonic speeds. The speed of light is unattainable by aircraft due to drag. We have no materials that could with stand the heat caused by the friction of the air moving over its body, nor materials strong enough to be able to take the enormous drag. Today there is no thrust capability that would allow for the speed of light. Although aircraft has proved such things as time dilation it is still impossible for an aircraft to travel at 900,000 miles per second.
Major Ted Tolman’s F-105 Thud fighter/bomber streaked through the air at just under the speed of sound. His aircraft performed modestly at best, struggling to maintain its speed and altitude under the heavy load of ordinance and fuel it carried under its wings (Patrick).
4.Exhaust: After the Air/Fuel mix has been burnt the remaining chemicals in the cylinder (water and CO2 for the most part) must be removed so that fresh air can be brought in. As the piston goes back up after combustion the exhaust valve opens allowing the exhaust gasses to be released.
Following World War II and the jet engine technology that emerged largely toward its end, aerospace engineers knew well that the technology had great potential for use in the commercial aviation industry. The Comet was the first aircraft to utilize jet propulsion; however, its designers failed to consider the metallurgy of the aircraft’s materials under flight conditions or the consequences of their atypical window design. The aircraft was designed by Britain’s De Havilland Aircraft Company and entered service in May 1952. After a year of service, however, the design issues mentioned above resulted in the failure of several Comet aircraft. Extensive evaluations revealed that repeated pressurization stress on the aircraft’s main cabin had caused its structure to fail.
Many people are amazed with the flight of an object, especially one the size of an airplane, but they do not realize how much physics plays a role in this amazing incident. There are many different ways in which physics aids the flight of an aircraft. In the following few paragraphs some of the many ways will be described so that you, the reader, will realize physics at work in the world of flight.
For a plane to create lift, its wings must create low pressure on top and high pressure on the bottom. However, at the tips of the wings, the high pressure pushes and the low pressure pulls air onto the top of the wing, reducing lift and creating a current flowing to the top. This current remains even after the wing has left the area, producing really awesome vortices.
Travelling at a speed twice that of sound might seem to be something futuristic; however, this feat has already been achieved almost 40 years ago by the world’s only supersonic passenger aircraft-The Concorde. Concorde brought a revolution in the aviation industry by operating transatlantic flights in less than four hours. The slick and elegant aircraft with one of the most sophisticated engineering was one of the most coveted aircrafts of its time. However, this was all destined to end when Air France Flight 4590 was involved in a tragic disaster just outside the city of Paris on July 25, 2000. The crash killed 113 people, but more disastrous was its impact. The belief and confidence people had with Concorde gradually started to fade, and finally Concorde was grounded after two and a half years of the crash. Official reports state that the main cause of the crash was a piece of metal dropped by a Continental aircraft that flew moments before Concorde, but, over the last decade, the report has met a lot of criticism, and many alternative hypotheses have thus been proposed.
This hot gas is pushed out through the back and it makes the rocket move forward. This is using Newton's third law of
When a rocket is in flight, the force of the air pushing on it keeps the Cp behind the Cg. This is important because the rocket is pushed by the force of the exhaust coming out the back. If the Cp was in front of the Cg, the rocket would want to spin around (so that its back was pointing forwards).. However, because the exhaust is always pushing the rocket forward, it spins around again and again... and you get the picture from there.
Firstly, the gas turbine engine operation begins with the air intake process. As of all internal combustion engine, oxygen is required to support the combustion of the fuel and the source of oxygen is from the fresh air that is taken in. Initially, the fan is rotated by a driving shaft that is powered by the turbine of the engine. A negative or vacuum pressure at the intake side is then created by the rotating fan. Next, the surrounding air is drawn towards the inlet and causes it to flow into the gas turbine engine inlet (Cengel & Boles, 2011). At the same time, the pressure on the other side of the fan is increased as it is compressed at a lower pressure ratio and causes the air in the outlet side of the fan to move fu...
(Morgan 67). When the jet engine was thought of back in the 1920's the world
The jet engine is a great mechanical piece of engineering. It has been used in almost all aircraft since its invention. This one improvement in aircraft allowed aircraft to fly higher, faster, and more efficient. The turbocharged engine invented by GE was the main building block for other engines. Since its invention, the jet engine has been the workhorse for all jet powered aircraft.
... turned by pistons, it is fueled by a combustion process using turbine exhaust to spin the prop rather, hence the term turboprop. A turbofan is what you will find on all private business jets and airliners. Instead of turning a prop, turbofan engines use the exhaust to turn a fan which helps produce more thrust by helping creating bypass air. Military planes such as the F-22 Raptor use the plain jet engine which produces thrust by in simple terms lighting jet fuel on fire and pushing it out the back. Whatever type of engine it may be, they are all important pieces of a plane.
This experiment will be conducted outdoors using water, a bottle, and launching equipment. All three of Newton’s laws will apply to this water rocket lab. The pressure will be measured in pounds per square inch (psi) using the bicycle pump and the horizontal displacement will be measured as the linear distance in meters (m) from the launching site to the location of first impact.
A in November 1962, the British and French governments agreed to develop and build a supersonic aircraft. Each design presents an aerodynamic supersonic aircraft with a range of difficult problems, including two that have the highest interest powerplant installation and design of subsonic aircraft. supersonic speed because it is there are many configuration changes have been introduced, particularly in the areas of the nose and visor, rear wing and fuselage. the head of...