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Файл:English for engineers in construction mechanization and automation (Коммуникативный метод обучения профессиональному английскому языку). Учебное пособ
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Unit 3. ENGINES AND MOTORS
Vocabulary
1) an output
производительность; мощность, отдача;
пропускная способность; ёмкость
2) a motion
движение, ход
3) a combustion
горение
4) a device
устройство, приспособление;
механизм; аппарат, машина, прибор
5) to eject
извергать, выбрасывать, выталкивать
6) a fuel
топливо, горючее
7) gasoline
бензин
8) to ignite
воспламенять, зажигать; раскалять
9) to occur
происходить, случаться, совершаться
10) residual
остаточный
11) a substance
вещество
12) a shaft
вал, ось, шпиндель
13) a piston
поршень; плунжер
14) a stator
статор двигателя
15) hydraulic
гидравлический
Text 1.
MOTOR VS ENGINE
The dictionary definition of “motor” represents it as a machine that
produces kinetic power as the primary output and sends it to
an automobile or other devices. On the other hand, an “engine” is a com-
plex machine with moving components that transform power into motion.
1. Motor.
Most motors these days are electrical motors and they transform electrical power into mechanical energy. You can divide them into two broad
categories – AC motor and DC motor. AC current is the power behind
running AC motors while DC electricity runs DC motors. You can divide
these two types into more categories based on horsepower, power rating,
and other factors.
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2. Engine.
The engine is a mechanical component that converts any form energy
into mechanical power. Based on the functions, you can put them into
several groups. For example, combustion engines transform heat into
mechanical power while hydraulic engines produce mechanical energy
from pressurized fluids. Similarly, the electrical engines convert electrical power.
Motor vs Engine: The Components. The mechanism of these two
devices are quite different and they also have different types of components. The engine has cylinders and pistons. The piston moves by the pressure created by the burnt fuel and pushes the cylinder to move. A motor
has a rotor and stator instead. The supplied electricity creates an electromotive force that makes the rotor to move and generate mechanical power.
Motor vs Engine: The Differences. As the definitions suggest, these
are completely two different types of devices with separate functions.
1. Answer the following questions:
1. What is the definition of word “motor”?
2. What types of motors do you know?
3. What is engine?
4. What do you know about the mechanism of these devices?
5. What is the difference between motor and engine?
6. What main functions have motor and engine?
2. Fill in the gaps to know their differences:
Engine
Motor
The word “engine” usually refers
to the reciprocating engine variations such as ……. combustion or
steam engines.
The word “motor” is commonly
used to indicate a rotating device
such as an ……. motor.
It produces ……. power from
chemical energy.
It transforms electrical energy
into ………. energy.
Most engines are run by ……….
Motors mostly run on ………. or
batteries.
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………. is needed for its components to run continuously with
reduced friction.
No lubrication is needed.
Main components are …. and
cylinders.
Coils and rotors are the main …
of motors.
Given that both devices produce
the same power, an engine is
heavier than a motor.
Motors are lighter than engines.
Engines are less efficient than
motors because the ratio of fuel
to converted energy is lower.
Motors are highly efficient because
the percentage of lost power is
minimal.
Engines are ……...
Motors are relatively ………
Examples: Cars, trains, large
ships, and more.
Examples: fans, washing machines,
vacuum cleans, and more.
Text 2.
Vocabulary
1) vapor
пар; пары; испарения
2) a chamber
камера
3) a stroke
удар
4) to expel
выбрасывать, выталкивать
5) to render
приводить в какое-л. состояние
6) a nozzle
сопло; форсунка, выпускное отверстие; наконечник; патрубок
7) a thrust
опора, упор, осевая нагрузка
8) a crankshaft
коленчатый вал
9) a propulsion
силовая установка, двигатель
импульс, толчок
10) interstellar
межзвёздный
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ENGINES
Self-contained devices that convert electrical, chemical, or nuclear energy into mechanical energy are called motors and engines. In many areas
of the world they have replaced human and animal power by providing energy for transportation and for driving all kinds of machines. The chemical
energy of a fuel can be converted by combustion into thermal, or heat,
energy in a heat engine. The engine in turn converts the thermal energy
into mechanical energy, as in engines that drive shafts. When the combustion occurs within the same unit that produces the mechanical energy, the
device is called an internal-combustion engine. Automobile gasoline or
diesel engines are internal-combustion engines. The steam engine, on the
other hand, is an external-combustion engine the boiler is separate from the
engine. Electric motors convert electrical energy into mechanical energy.
Heat Engines. The term heat engine includes all engines that produce
work, or the transference of energy, by operating between high and low
temperatures and often between high and low pressures as well. The most
widely used heat engines are internal-combustion engines, particularly
gasoline engines.
Gasoline engines run on a mixture of air and gasoline vapor, which is
usually drawn into a piston-cylinder arrangement and compressed by a piston. As the volume of the chamber decreases, the pressure and temperature
within it increase. Near the point of maximum compression, the fuel vapor
is ignited by a spark. The hot gases expand and force the piston down
in what is called the power stroke, delivering work through the piston rod
to the crankshaft. The residual gases are then expelled, and the process is
repeated.
Diesel engines initially compress air to a much higher pressure and
temperature than do gasoline engines. The fuel is then injected and ignites
without a spark. The higher pressures required render diesel engines
heavier and more expensive than gasoline engines; however, they are
generally more efficient. They are used primarily in buses, trucks, locomotives, and in some power plants.
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Gas turbine engines use a rotary compressor to compress a continuous flow of incoming air, thereby increasing the air's temperature. The air
then passes through a combustion chamber, where fuel is injected and
burned. The gas, which is at a high pressure and temperature, expands
through a turbine, providing the power to drive the compressor. At the turbine exit the gases are still at a temperature and pressure above that of the
outside air. Gas turbine engines are less efficient than diesels but can produce more power for a given size. They are often used for stand-by power
by electric utilities.
Rocket engines use two chemicals that, when combined, release
chemical energy that increases the temperature and pressure in the rocket
chamber. The hot gases are then allowed to expand through a nozzle to
produce thrust. The fuels may be liquid or solid. Because rocket engines
can work outside of the Earth's atmosphere, they are the propulsion systems used in spacecraft.
Steam engines are external-combustion engines that burn fuel in a
separate boiler to produce steam at high pressure and temperature. The
steam then expands in a reciprocating engine or a turbine. The lowpressure steam is normally condensed to water before being pumped back
into the boiler. In a steam locomotive, however, the expanded steam is
blown off.
Ion engines have been proposed for space flight. Their source of fuel
would be an easily ionizable substance, such as cesium metal, to supply
ions, or charged particles. A generator or solar batteries would produce an
electric field that would repulse the ions strongly enough to eject them
from the engine, thereby generating thrust. Such engines would produce
very little thrust, but they should be able to operate for long periods in
interstellar flight.
1. Answer the following questions:
1. What types of engines do you know?
2. What kind of energy do engines use?
3. What does gas turbine engine use?
4. What is the difference between gasoline and diesel engines?
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5. What engines can be used for space flight?
6. Describe the difference between internal and external-combustion
engines?
7. What are the functions of the engine?
2. Explain how the engine works, using this scheme:
3. Translate sentences from Russian into English:
1. Словарь Ожегова толкует слово «мотор» как двигатель внутреннего сгорания или электрический двигатель. Само слово «мотор»
было заимствовано из немецкого языка.
2. Мотор в большинстве случаев обозначает электродвигатель
или ДВС, тогда как двигатель включает в себя более широкий спектр
понятий.
3. Двигатель – это механическое или электрическое устройство,
генерирующее вращательное или линейное усилие, используемое для
движения механизмов.
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4. Двигатели подразделяют на первичные и вторичные. К первич-
ным относят непосредственно преобразующие природные энергетические ресурсы в механическую работу, а ко вторичным – преобразующие энергию, выработанную или накопленную другими источниками.
5. Проект первого двигателя внутреннего сгорания (ДВС) принадлежит известному изобретателю Христиану Гюйгенсу и был предложен
ещё в XVII веке.
6. В XX веке ДВС стал основным двигателем в автомобильном
транспорте.
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Unit 4. ELECTRICITY
Vocabulary
1) to occur
происходить, случаться, совершаться
2) hydrogen
водород
3) carbon
углерод
4) oxygen
кислород
5) copper
медь
6) tiny
очень маленький, крошечный
7) to dive
нырять
8) outer
внешний, наружный, поверхностный
Text 1.
WHAT IS ELECTRICITY?
Any appliances that we use in our daily lives such as household appliances, office equipment and industrial equipment, almost all of those
things take electricity. Therefore, we should understand electricity. The
first question that we will find out the answer is "where does electricity
come from?"
Electricity is a natural phenomenon that occurs throughout nature and
takes many different forms. How does electricity flow from a power
source through wires, lighting up LEDs, spinning motors, and powering
our communication devices? Electricity is briefly defined as the flow of
electric charge, but there's so much behind that simple statement. To understand the fundamentals of electricity, we need to begin by focusing in
on atoms, one of the basic building blocks of life and matter.
Atoms exist in over a hundred different forms as chemical elements
like hydrogen, carbon, oxygen, and copper. Atoms of many types can
combine to make molecules, which build the matter we can physically see
and touch. Atoms are tiny, stretching at a max to about 300 picometers
long. Even the atom isn't small enough to explain the workings of electricity. We need to dive down one more level and look in on the building
blocks of atoms: protons, neutrons, and electrons.
An atom is built with a combination of three distinct particles: electrons, protons, and neutrons. Each atom has a center nucleus, where the
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protons and neutrons are densely packed together. Every atom must have
at least one proton in it. The number of protons in an atom is important,
because it defines what chemical element the atom represents. For example, an atom with just one proton is hydrogen, an atom with 29 protons is
copper, and an atom with 94 protons is plutonium. This count of protons is
called the atom's atomic number.
The proton's nucleus-partner, neutrons, serve an important purpose;
they keep the protons in the nucleus and determine the isotope of an atom.
They're not critical to our understanding of electricity, so let's not worry
about them for this tutorial.
Electrons are critical to the workings of electricity. In its most stable,
balanced state, an atom will have the same number of electrons as protons.
As in the Bohr atom model, a nucleus with 29 protons is surrounded by an
equal number of electrons. The atom's electrons aren't all forever bound to
the atom. The electrons on the outer orbit of the atom are called valence
electrons. With enough outside force, a valence electron can escape orbit
of the atom and become free. Free electrons allow us to move charge,
which is what electricity is all about.
1. Answer the questions:
1. What is electricity?
2. What is the origin of the
electricity?
3. What parts does atom consist
of?
4. What is an electron?
5. What are the main parts of
atom?
6. What is a proton?
7. How does electricity work?
8. What purpose do you use electricity at home or at work for?
https://learn.sparkfun.com/tutorials/what-is-
electricity/all
31
2. Complete the sentences with the missing information.
1. Elements make up ______________________________________.
2. Identical atoms _________________________________________.
3. Atoms consist of ________, __________and _________________.
4. Inside there are _________ and ________, while outside ________.
5. Valence electrons _______________________________________.
6. Neutrons do not have ____________________________________.
7. Electricity is generated when ______________________________.
3. What statements are true (T) and false (F), correct the false
ones.
1. A flow of electrons moving inside a conductor creates an electric
current.
2. A generator is used to move the charges.
3. Electrons can easily pass through any material.
4. Any material is a good conductor.
5. Conductors are coated with insulators.
6. The presence of free electrons affects the conductivity of materials.
7. Impurities are introduced to increase conductivity.
8. Insulating materials resist the flow of electrons.
Text 2.
Vocabulary
1) to charge
заряжать (аккумулятор)
2) coated
покрытый, облицованный
3) a conductor
проводник
4) a current
ток
5) a flow
поток
6) impurity
загрязнение
7) an insulator
диэлектрик; изолятор; непроводник
8) halfway
наполовину; отчасти
9) a transistor
транзистор, кристаллический триод
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