Paper
The Evolution of Jet Engines
The jet engine is a complex propulsion device which draws in air by
means of an intake, compresses it, heats it by means of an internal combustion
engine, which when expelled it turns a turbine to produce thrust, resulting in a
force sufficient enough to propell the aircraft in the opposite direction
(Morgan 67). When the jet engine was thought of back in the 1920’s the world
never thought it would become a reality, but by 1941 the first successful jet
flight was flown in England. Since then the types of engines have changed, but
the basic principals have remained the same.
In 1921 thoughts of a jet engine were based upon adaptations of piston
engines and were usually very heavy and complicated. These thoughts were
refined in the 1930’s when the turbine engine design lead to the patent of the
turbojet engine by Sir Frank Whittle of Great Britian. It was Sir Whittle’s
design that lead Great Britian into the jet age with the first successful flight.
At the same time, the Germans were designing there own jet engine and aircraft
which would be one of the factors that kept Germany alive in World War II. With
technological advances by the allies a prototype turbojet known as the “Heinkel
He 178″ came into a few operational squadrons in the German, British, and the
American air forces towards the end of World War II. These jets finally helped
the allies to win the war against the axis powers(Smith 23-27).
A later development in the jet industry was the overcoming of the sound
barrier and establishing normal operations up to and beyond twice the speed of
sound. Also air force bombers and transports were able to reach and cruise at
supersonic speeds(Silverstein 56-70). In the late 1950’s civil transcontinental
jet services started with the Comet 4 and the Boeing 707. In the mid 1960’s all
major jet manufacturing companies revised their present engines with new
materials such as aircraft aluminium which made them lighter and turbine changes
so they could compress the air at a much higher pressure so the engine can
produce much more thrust.The first supersonic airliner is the twin turbojet
Concorde which flies at over twice the speed of sound which was brought into
regular service in 1976(Smith 27-30). The one company that dominates the
private jet industry is Bombardier which makes the Learjet turbofans, they have
an approximate cruising distance of 1880 nautical miles(Jennings 103).
In the future, turbojet engines will continue to further develop due to the
technological advances made. As in graphite composite wings, thermoplastic
chassis, and kevlar skins that have changed the weight of modern planes and
gliders. With these and other developments jet engines will be honed to produce
greater thrust without increases in weight or size. Which will involve small
refinements rather than major changes to the existing engine and engine
compartment. In the near future there will be a substantial reduction of noise
emitted from the jet engine, due to a change in materials and a reduction of
vibration in the housing. Right now the jet industry has over one thousand jets
operational at one time, which poses the threat of malfunction and crashes. With
the new computer analysis of problems and the new materials found in the
internals of the engines, there is less of a risk of malfunction than in the
past.
Many factors have lead to the popular take over of the jet, replacing the
traditional propeller driven planes. Some of the basic reasons are the speed,
fuel economy, and endurance of the jet engine oveer piston-driven engines.
Together with the new refinements and the currently changing jet industry,
future transportation will become faster and safer for the flier.
! |
Как писать рефераты Практические рекомендации по написанию студенческих рефератов. |
! | План реферата Краткий список разделов, отражающий структура и порядок работы над будующим рефератом. |
! | Введение реферата Вводная часть работы, в которой отражается цель и обозначается список задач. |
! | Заключение реферата В заключении подводятся итоги, описывается была ли достигнута поставленная цель, каковы результаты. |
! | Оформление рефератов Методические рекомендации по грамотному оформлению работы по ГОСТ. |
→ | Виды рефератов Какими бывают рефераты по своему назначению и структуре. |