Техническое чтение для энергетиков. Бухарова Г.П. - 68 стр.

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70
decided to spend $800 million a year on the development of new car technology.
Many engineers believe that the electric car will lead to other forms of technology
being used for transportation.
Car companies are working at developing a supercar. A super-efficient car will
have an electric motor. Four possible power sources are being investigated. The
simple one is batteries. Another possibility is fuel cells, which combine oxygen from
air with hydrogen to make electricity. Yet another approach would be a flywheel
(маховик), an electric generator consisting of free-spinning wheels with magnets in
the rims that can produce a current. A fourth possible power source for the super-car
would be a small turbine engine, running on a clean fuel like natural gas. It would run
at a constant speed, generating electricity for driving vehicles or for feeding a bank of
batteries, storing energy for later use.
ENGINES
Do you know what the first engine was like? It was called the «water wheel».
This was an ordinary wheel with blades fixed to it, and the current of a river turned it.
These first engines were used for irrigating fields.
Then a wind-powered engine was invented. This was a wheel, but a very small
one. Long wide wooden blades were attached to it. The new engine was driven by the
wind. Some of these ones can still be seen in the country.
Both of these, the water- and wind-operated engines are very economical. They
do not need fuel in order to function. But they are dependent on the weather.
Many years passed and people invented a new engine, one operated by steam.
In a steam engine, there is a furnace and a boiler. The furnace is filled with wood or
coal and then lit. The fire heats the water in the boiler and when it boils, it turns into
steam which does some useful work.
The more coal is put in the furnace, the stronger the fire is burning. The more
steam there is, the faster a train or a boat is moving.
The steam engine drove all sorts of machines, for example, steam ships and
steam locomotives. Indeed, the very first aeroplane built by A.F. Mozhaisky also had
a steam engine. However, the steam engine had its disadvantages. It was too large
and heavy, and needed too much fuel.
The imperfections of the steam engine led to the design of a new type. It was
called the internal combustion engine, because its fuel ignites and burns inside the
engine itself and not in a furnace. It is smaller and lighter than a steam engine
because it does not have a boiler. It is also more powerful, as it uses better-quality
fuel: petrol or kerosene.
The internal combustion engine is now used in cars, diesel locomotives and
motor ships. But to enable aeroplanes to fly faster than the speed of sound another,
more powerful engine was needed. Eventually, one was invented and it was given the
name «jet engine». The gases in it reach the temperature of over a thousand degrees.
It is made of a very resistant metal so that it will not melt.

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