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Rolls-Royce has developed the Trent family of large
turbofans. These Trent engines carry advanced technology
features and are designed to have a minimum impact on
the environment.
Power
The power a Trent engine generates at take off is about
90,000 horsepower. This is equivalent to the power of
1,200 family-sized cars and the same amount of energy
used as 250,000 people jogging at the same time.
The total power generated by the turbines in order
to drive the fan and compressors is about 250,000 horsepower.
There are 92 high pressure turbine blades in a Trent
800 engine. Each of these generates about 800 horsepower,
which is equivalent to a Formula 1 racing car.
Efficiency
The Boeing 777, which is powered by two Trent 800 engines,
carries around 330 passengers and gives about 120 passenger-miles
to the gallon. This is equivalent to a family-sized
car travelling at 40 miles per hour. However, the Boeing
777 travels 10 times faster.
Reliability
The Trent achieves around 13,000 flying hours between
major overhauls, demonstrating the reliability typical
of big Rolls-Royce engines. This is equivalent to 7
million miles or flying around the world 250 times.
Airflow
While generating its 92,000lb thrust, the Trent sucks
in more than 1 ton of air per second at about 350 miles
per hour. This is equivalent to emptying a squash court
of air in less than one second. By the time the air
leaves the nozzle at the back of the engine, it has
been accelerated to a speed of 1050 miles per hour.
Extremes of temperature
Fuel burns in the Trent engine's combustion chamber
at temperatures up to 2,000°C, which is well above
the 1,300°C at which some component metals used
would start to melt, so a very sophisticated cooling
system is needed. The heat transfer rate achieved by
the cooling air system in each High Pressure Turbine
blade is equivalent to a domestic central-heating boiler
or air-conditioning unit.
Strength
Components in the Trent are subject to extreme forces
which make high demands on the special alloys used in
their construction.
The force on a fan blade at take-off is equivalent
to a load of almost 100 tonnes. This is equivalent to
hanging a main-line diesel locomotive or a Boeing 757
on each blade.
The force on the small first stage turbine blade is
about 10 tonnes. This is equivalent to hanging a double-decker
London bus on each blade.
Speed
The tip speed of the Trent fan blades and first stage
turbine blades is about 1,500 ft per second or over
1,000 miles per hour.
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