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Hydroelectric Power-Station



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Thermal Power-station

 

A modern thermal power-station is known to consist of four principal components, namely, coal handling and storage, boiler house, turbine house, switchgear.

If you have not seen a power-station boiler it will be difficult for you to imagine its enormous size.

Besides the principal components mentioned above there are many additional parts of the plant. The most important of them is the turbogenerator in which the current is actually generated.

A steam turbine requires boilers to provide steam. Boilers need a coal-handling plant on the one hand and an ash-disposal plant on the other. Large fans are quite necessary to provide air for the furnaces. Water for the boilers requires feed pumps. Steam must be condensed after it has passed through the turbines, and this requires large quantities of cooling water. The flue gases carry dust which must be removed by cleaning the gases before they go into the open air.

A modern thermal power-station is equipped with one or more turbine generator units which convert heat energy into electric energy. The steam to drive the turbine which, in its turn, turns the rotor or revolving part of the generator is generated in boilers heated by furnaces in which one of three fuels may be used-coal, oil and natural gas. Coal continues to be the most important and the most economical of these fuels.

At present great attention is being paid to combined generation of heat and electricity at heat-and-power plants and to centralized heat supply. One of the world’s largest heat-and-power installations is operating at the Moskowskaya thermal power-station-25.

Thermal power-stations are considered to be the basis of our country’s power industry. More than 80% of the country’s total power output comes from the above stations. It is necessary to say that separate power-stations in our country are integrated into power systems. Integration of power systems is a higher stage in the scientific and technical development of power engineering.

ТЭС

Современные тепловые электростанции, как известно, состоят из четырех основных компонентов, а именно, погрузка и хранение угля, котельная, турбина дом, ру.
Если Вы не видели электростанции котел, это будет трудно для вас, чтобы представить его огромных размеров.
Помимо основных компонентов, упомянутых выше, есть много дополнительных частей растения. Наиболее важным из них является турбогенератор, в котором ток создается.
Паровая турбина требует котлов, чтобы обеспечить паром. Котлы нужен уголь-обработка растений, с одной стороны, и пепельно-завод по утилизации на другие. Большие вентиляторы весьма необходимы, чтобы обеспечить доступ воздуха для печи. Воды для котлов требует питательных насосов. Пара должна быть сокращенной после прохождения через турбины, а это требует большого количества воды для охлаждения. Дымовых газов забивается пылью, которые должны быть удалены путем очистки газов, прежде чем они идут на открытый воздух.
Современная тепловая электростанция оснащена одной или более турбин-генераторов, которые преобразуют тепловую энергию в электрическую энергию. Пара для привода турбины, которая, в свою очередь, вращает ротор или вращающаяся часть генератора создается в котлах, отапливаемых печами, в которых один из трех видов топлива-угля, нефти и природного газа. Уголь продолжает быть самым важным и самым экономичным из этих видов топлива.
В настоящее время большое внимание уделяется комбинированной выработки тепла и электроэнергии на тепло-и электростанций и централизованного теплоснабжения. Один из крупнейших теплоэнергетических установок, работающих на Moskowskaya ТЭС-25.
Тепловые электростанции являются основой нашей энергетики страны. Более 80% страны Суммарная мощность исходит от вышеуказанных станций. Надо сказать, что отдельные электростанций в нашей стране объединены в энергосистемы. Интеграция энергетических систем является более высокой стадии научно-технического развития энергетики.

VI. Письменно ответьте на вопросы по содержанию текста:

1. What does a modern thermal power-station consist of?

2. What is the efficiency of such power-stations?

3. 1. Что делает современная тепловая электростанция состоит?
2. Какова эффективность таких электростанций?

 

Вариант II

I. Перепишите предложения. Переведите на русский язык, обращая

внимание на перевод герундия. Подчеркните герундий в предложениях.

 

1. On splitting atoms in the reactor, heat is developed.

2. Franklin's having worked in the field of electricity is known the world over.

3. After completing the computations of the problems the personal computer displayed the answers.

4. In studying magnetism, we cannot help observing the relations between magnetism and the electric current.

5. 1. На расщепление атомов в реакторе, тепла.
2. Франклина проработав в области электричества известна во всем мире.
3. После завершения вычислений проблем персонального компьютера отображаются ответы.
4. В изучении магнетизма, мы не можем помочь наблюдая отношения между магнетизма и электрического тока.

 

II. Перепишите предложения, подчеркните причастия. Переведите

предложения на русский язык. Укажите № предложения, в котором

употреблен независимый причастный оборот.

 

1. Having invented the lightning conductor, Franklin continued working at the problem of atmospheric electricity.

2. Unless translated into a machine code the high level language must not be used by any computer.

3. The energy sources of the world decreasing, it is necessary to turn to atomic energy.

4. Water falling from its raised position changes potential energy into kinetic energy.

5. While developing the new automated management systems, engineers use modern PCs (Personal Computers).

6. They saw the laboratory assistant demonstrating a new electrical device.

 

 

III. Перепишите предложения и переведите их на русский язык.

Подчеркните в придаточных предложениях глаголы в сослагательном

наклонении.

 

1. Should there be even a small deviation in the velocity, the space vehicle would pass the planet.

2. The engineer demanded that the test be repeated.

3. I wish you had operated those computers more carefully.

4. It is desirable that this new electronic device should be tested in this laboratory.

IV. Перепишите предложения. Переведите на русский язык, обращая

внимание на условные придаточные предложения.

1. If we look around, we can see that electricity is serving us in one way or another.

2. Provided the operator’s cabin had been equipped with electronic control, he would have been able to work faster and with greater precision.

3. Were electric motors used, cars would not pollute the air, would be practically noiseless and very easy to control.

 

V. Прочитайте текст, перепишите его и письменно переведите на

русский язык.

Hydroelectric Power-Station

 

Water power was used to drive machinery long before Polzunov and James Watt harnessed steam to meet man’s needs for useful power.

Modern hydroelectric power-stations use water power to turn the machines which generate electricity. The water power may be obtained from small dams in rivers or from enormous sources of water power. However, most of our electricity, that is about 86 per cent, still comes from steam power-stations.

The locality of a hydroelectric power plant depends on natural conditions. The hydroelectric power plant may be located either at a dam or at a considerable distance below. That depends on the desirability of using the head supply at the dam itself or the desirability of getting a greater head. In the latter case, water is conducted through pipes or open channels to a point farther downstream where the natural conditions make a greater head possible.

The design of machines for using water power greatly depends on the nature of the available water supply. In some cases great quantities of water can be taken from a large river with only a few feet head. In other cases, instead of a few feet, we may have a head of several thousands of feet. In general, power may be developed from water by the action of its pressure, of its velocity, or by a combination of both.

A hydraulic turbine and a generator are the main equipment in a hydroelectric power-station. Hydraulic turbines are the key machines converting the energy of flowing water into mechanical energy. Such turbines have the following principal parts: a runner composed of radial blades mounted on a rotating shaft and a steel casing which houses the runner. There are two types of water turbines, namely, the reaction turbine and the impulse turbine. The reaction turbine is the one for low heads and a small flow. Modified forms of the above turbine are used for medium heads up to 500-600 ft, the shaft being horizontal for the larger heads. High heads, above 500 ft, employ the impulse- type turbine.

Hydropower engineering is developing mainly by constructing high capacity stations integrated into river systems known as cascades. Such cascades are already in operation on the Dnieper, the Volga and the Angara.

 

VI. Письменно ответьте на вопросы по содержанию текста:

1. What does the locality of a hydroelectric power plant depend on?

2. What is the key machine for converting the energy of water into mechanical energy?

 

Вариант III

I. Перепишите предложения. Переведите на русский язык, обращая

внимание на перевод герундия. Подчеркните герундий в предложениях.

 

1. Protecting buildings from strokes of lighting was a great achievement in the field of electricity.

2. Supercomputers are used for calculating complex problems.

3. His taking part in the development of the new semiconductor device was of great help to us.

4. Besides using optical telescopes scientists are extensively employing radio telescopes, which are huge antennae, and constantly listening to the radio signals coming from our distant neighbours in the Universe.

II. Перепишите предложения. Подчеркните причастия. Переведите

предложения на русский язык. Укажите № предложения, в котором

употреблен независимый причастный оборот.

 

1. In future, the nuclear reactor will be one of the most reliable “furnaces” producing atomic energy.

2. Atomic energy being developed in a reactor in the form of heat, we can get both heat and electrical energy.

3. Having been translated into a machine language any high level programming language can be used by any computer.

4. Knowing how to detect radio signals emitted by the Sun and other heavenly bodies people can greatly enlarge their possibilities of observing the universe.

5. When passed through the reading equipment (устройство ввода) the characters are read into the memory of a PC (Personal Computer).

6. The students heard the professor speaking about his experimental work.

III. Перепишите предложения и переведите их на русский язык, обращая

внимание на глаголы в сослагательном наклонении.

1. Without radioelectronics there would be no cybernetic, cosmonautic or nuclear physics.

2. The electrons move round the nucleus as if they were the planets of the solar system moving round the sun.

3. It is essential that a superconductor should be cooled to - 273˚C.

4. The substance should be purified so that it might be used for this purpose.

IV. Перепишите предложения. Переведите на русский язык, обращая

внимание на условные придаточные предложения.

1. If there were no computers, space flights would be impossible.

2. If atomic energy replaces the present sources of energy, we shall get more energy than we produce at present.

3. Had there been no Earth`s gravitational, the artificial satellites would have moved through airless space in a straight line at a uniform speed.

V. Прочитайте текст, перепишите его и письменно переведите на

русский язык.

Nuclear Power Plant

 

The heart of the nuclear power plant is the reactor which contains the nuclear fuel. The fuel usually consists of hundreds of uranium pellets placed in long thin cartridges of stainless steel. The whole fuel cell consists of hundreds of these cartridges. The fuel is situated in a reactor vessel filled with a fluid. The fuel heats the fluid and the superhot fluid goes to a heat exchanger, i.e. steam generator, where the hot fluid converts water to steam. The fluid is highly radioactive, but it should never come into contact with the water that is converted into steam. Then this steam operates steam turbines in exactly the same way as in a coal- or oil-fired power-plant.

A nuclear reactor has several advantages over power-plants that use coal or natural gas. The latter produce considerable air pollution, releasing combusted gases into the atmosphere, whereas a nuclear power plant gives off almost no air pollutants. As to nuclear fuel, it is far cleaner than any other fuel for operating a heat engine. Furthermore, our reserves of coal, oil and gas are decreasing so nuclear fuel is to replace them. It means that coal and oil can be used for some other purposes. The amount of nuclear fuel which the nuclear power-plant consumes is negligible, while the world’s uranium and thorium resources will last for hundreds of years.

The construction of the first world’s nuclear power-plant in Obninsk near Moscow, was a great historical event and the beginning of atomic energetics. Since then our country has achieved great progress in this field. It should be noted that while the unit capacity of the Obninsk nuclear power-plant was five thousand kW, that of the first unit of the Leningradskaya nuclear power-plant was one million kW.

Our country produces two main types of reactors namely vessel-type reactors and channel-type reactors.

It is necessary to mention here that channel-type reactors have been operating since 1954 at the world’s first nuclear power-plant and in the far North-East of our country, where they produce both electricity and heat.

The nuclear power-stations are mostly designed for the generation of electricity. If a station generates only electric energy, it is equipped with condensing turbines and the station is known as a condensing one. At present, nuclear power-stations mainly operate as condensing plants. The nuclear power-station designed to produce not only electrical energy but also heat are called nuclear heat-and-power plants.

 

VI. Письменно ответьте на вопросы по содержанию текста:

1. What are the advantages of nuclear power plants over power plants?

2. What two types of reactors are mentioned in the text?

 

Вариант IV

 

I. Перепишите предложения. Переведите на русский язык, обращая

внимание на перевод герундия. Подчеркните герундий в предложениях.

 

1. Using atomic fuel for the production of electricity is one of the most perspective sources.

2. A fax machine is used for sending and receiving copies of original documents via phone line.

3. Lomonosov’s having studied atmospheric electricity contributed to the development of science.

4. After finishing calculations a supercomputer puts out necessary results.

 

II. Перепишите предложения, подчеркните причастия. Переведите

предложения на русский язык. Укажите № предложения, в котором

употреблен независимый причастный оборот.

 

1. The construction of power-stations operating on atomic fuel and generating electric current is quite necessary.

2. Having discussed the structure of a PC, we can explain its operation.

3. Atomic energy replacing the present sources of energy, the latter will find various new applications.

4. The equipment (элементная база) used in this control unit is the same as in the arithmetic unit.

5. While splitting atoms, scientists have learned to release much energy.

6. The students watched the operator using a new PC (Personal Computer).

 

 

III. Перепишите предложения и переведите их на русский язык, обращая

внимание на глаголы в сослагательном наклонении.

 

1. It is desirable that the engine should combine high efficiency and lightness.

2. K. Onnes found that it was necessary that a mercury wire be cooled to - 265˚C for electrical resistivity to disappear.

3. It is possible that a compound should become a superconductor even if the chemical elements constituting it are not.

4. If computers had not been invented, many important problems might never have been solved.

 

IV. Перепишите предложения. Переведите на русский язык, обращая

внимание на условные придаточные предложения.

 

1. These electrical devices can work for a long time, provided they are made of high-quality material.

2. Should a permanent magnet be moved in and out of a coil of wire, both the magnet and the coil would be used as a simple electric generator.

3. Unless the internal combustion engine had been invented, the automobile industry would not have begun to develop so rapidly all over the world.

 

V. Прочитайте текст, перепишите его и переведите на русский язык.

 

Transformers

The transformer is a device for changing the electric current from one voltage to another. As a matter of fact, it is used for increasing voltage. A simple transformer is a kind of induction coil. It is well known that in its usual form it has no moving parts. On the whole, it requires very little maintenance, provided it is not misused and is not damaged by lightning.

We may say that the principal parts of a transformer are two windings, that is coils, and an iron core. They call the coil which is supplied with current the “primary winding”, or just “primary”, for short. The winding from which they take the current is referred to as the “secondary winding” or “secondary”, for short. It is not new to you that the former is connected to the source of supply, the latter being connected to the load.

When the number of turns of wire on the secondary is the same as the number on the primary, the secondary voltage is the same as the primary, we get what is called a “one-to-one” transformer. In case, however, the number of turns on the secondary winding is greater than those on the primary, the output voltage is larger than the input voltage and the transformer is called a step-up transformer. On the other hand, the secondary turns being fewer in number than the primary, the transformer is known as a step-down transformer.

The transformer operates equally well to increase the voltage and to reduce it. By the way, the above process needs a negligible quantity of power. It is important to point out that the device under consideration will not work on d.c. but it is rather often employed in direct-current circuits. All radio sets and all television sets are known to use two or more kinds of transformers. These are familiar examples showing that electronic equipment cannot do without transformers.

 

Notes on the text:

one-to-one transformer – с соотношением 1:1

a step-up (a step-down) transformer –повышающий (понижающий) трансформатор

d.c. – direct current – постоянный ток

VI. Письменно ответьте на вопросы по содержанию текста:

1. What are the principle parts of a transformer?

2. What types of transformers are described in the text?

 



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