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Задание 3. Прочтите и переведите следующие предложения, обращая внимание на сослагательное наклонение.

1.Some parts of an internal combustion engine would melt from the heat of the burning gas if no cooling system were provided.

2.It would probably be more correct to refer to the engine cooling system as "a temperature regulation" system.

3.We would like to maintain the water jacket temperature slightly under the boiling point of water at all times if that were possible.

Задание 4. Прочтите текст "Cooling System", выделите смысловые части, и озаглавьте каждую из них.

COOLING SYSTEM

The petrol engine is only about 25% efficient. That is to say of all the potential energy in the fuel only a quarter is used to propel the car. Three gallons out of every four are wasted in heating up the engine. In fact so much heat is produced that the engine would become red hot and long before this happened it would seize up and cease to function.

Some parts of the internal combustion engine would melt from the heat of the burning gas if no cooling system were provided. However it would probably be more correct to refer to the engine cooling system as a "temperature regulation" system. We do not want the engine to run too hot neither do we want it to run too cool. We would like to maintain the water jacket temperature slightly under the boiling point of water or at about 200 deg.F.

There are two types of engines: water cooled and air cooled.

The cylinder walls of air cooled engines operate at a temperature considerably above 200 deg.F. in many cases. This is hot to touch, but cool in comparison with the heat generated in the combustion chamber of the engine.

As the fuel is burned in the combustion chamber, about one third of the heat energy of the fuel is converted into power.

Another third goes out the exhaust pipe unused, and remaining third must be handled by the cooling system.

It is interesting to note that the heat removed by the cooling system of a large motor truck at normal speed is sufficient to keep a thirty-five-room house warm in freezing weather. Even a passenger car engine will develop enough heat to keep a six-room house warm in zero weather.

This means that several gallons of cooling water must be circulated in the cooling system every hour to absorb the heat and carry it to the radiator. It also means that many thousands cubic feet of air must flow through the radiator every hour in order to dissipate the heat to the air. It is important to distinguish

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between heat transfer and heat dissipation.

The heat generated by the mixture burned in the cylinder must be transferred from the iron cylinder to the water in the water jacket.

The outside of the water jacket dissipates some of the heat to the air surrounding it, but most of the heat is carried by the cooling water on to the radiator from when it is dissipated to the air.

Thus the heat flows or transfers from the cylinder iron to the cooling water, and from the cooling water to the copper radiator.

Iron water and copper are all good conductors of heat, sо if they are in good contact, the heat will flow readily from one to another. If, however, there is a coating of lime or rust between the water and the bare metal the flow will be retarded because lime and mat are very poor heat conductors.

Air-Cooled Engines

Some cars are fitted with air cooled engines; in these the surface area of the cylinder block is very greatly increased by extensive finning and air is blown through the fins by means of a fan. The large area aids the transfer of heat to the air. A fan is generally mounted in front of the cylinder block. It is driven by the crankshaft via a fan-belt. The distance thermometer of the lubrication system controls the cooling system. The optimal temperature of oil should be from 55o to 100o C, and maximum – 120o С in extreme conditions. The air cooling creates the comfortable heat conditions for the engine, operating even with the surrounding temperature up to +55o C.

Задание 5. Пользуясь информацией текста, найдите английские эквиваленты для следующих слов и словосочетаний:

A). Surface area; air blow; fins; fan; to transfer the heat; in front of; crankshaft; via a fan-belt; lubrication system; oil; in extreme conditions; comfortable heat conditions.

B). Посредством ремня вентилятора; воздушный поток; спереди; внешняя поверхность; переносить тепло; внешние рёбра; система смазки; вентилятор; коленчатый вал; масло; благоприятный тепловой режим; тяжёлые условия.

Задание 6. Заполните пропуски в тексте следующими словами и словосочетаниями:

fins, crankshaft, to conduct, to control, the air-flow, to force.

1.Cylinders are constructed with many ... .

2.The cylinders are cooled by ... .

3.Heat is ... away from the cylinder and radiated into the air.

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4.The purpose of the fan is ... air through passages in the engine and over finned cylinders.

5.Fan is driven by ....

6.The distance thermometer ... the cooling system.

Задание 7. Ответьте на вопросы по теме "Air Cooling".

1.Why the surface area of the cylinder block is large?

2.What is the purpose of the fins around an air-cooled cylinder?

3.By means of what is air forced through passages in the engine?

4.By means of what operates the fan?

5.What is the purpose of distance termometer?

Задание 8. Опишите устройство и работу двигателя с воздушным охлаждением по рис.10.

При описании используйте уже известные Вам модели:

Глаголы и глагольные сочетания, используемые для описания процесса охлаждения двигателя:

to cool, to pass over, to blow through, to mount, to drive, to control, to force air through.

Задание 9. Закончите следующие предложения.

1.Some parts of the internal combustion engine would melt from the heat of the burning gas if...

2.We would like to maintain the water jacket temperature...

3.The cylinder walls of air cooled engines operate at...

4.The heat generated by the mixture burned in the cylinder must be transferred…

5.Most of the heat is carried by the cooling water on to…

Задание 10. Образуйте все возможные производные слова от дан-

ных:

cool, melt, heat, use, conduct, regulate, convert, radiator, possibility.

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Задание 11. Найдите ответ, соответствующий содержанию тек-

ста.

1.What is the function of the cooling system in an automobile engine?

2.What type of engine cooling system can be find in modern vehicles?

3.How much heat is created during the automobile operation?

4.What is the function of the water jacket?

Задание 12. Посмотрите на схему на с. 204 и назовите:

1.The main parts of the cooling system.

2.The functions of these parts.

Используйте следующие глаголы при выполнении задания: to cool, to pump, to transfer, to absorb, to carry, to dissipate, to flow, to maintain.

air blow cooling improved

by longer piston fins

fins

Рис.10

Текст 17

WATER-COOLED ENGINES

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The most common method to cool the engine is to circulate water, in a water jacket, round the cylinders. The water absorbs the heat and carries it away. The heated water is passed through a radiator in which it is cooled before being circulated again over the hot cylinders. The radiator is designed to expose a very large surface area to the air flow, maintained partly by the motion of the car and partly the action of the fan which belt is driven off the engine crankshaft.

The operation of the water-cooling system is controlled by the distance thermometer. The thermostat automatically maintains the required temperature of the engine.

Pressurised systems.

On modern cars the cooling system is "pressurised". The filler cap has a spring loaded valve in it to maintain the pressure in the radiator about 10 pounds per square inch above normal atmospheriс pressure. This increased pressure raises the boiling point of the water and increases the running temperature of the engine slightly. A second valve in the filler cap allows air into the system as the water cools and thus avoids the formation of a partial vacuum.

Задание 1. Изучите рис. 11 и подберите русские эквиваленты терминов, обозначающих элементы двигателя с водяным охлаждением. Проверьте себя по специальному словарю.

1)filler cap; 2) radiator; 3) water pump; 4) fan; 5) drain tap; 6) top hose;

7)thermostat; 8) water jacket; 9) bottom hose; 10) thermometer; 11) sensor; 12) cylinder; 13) oil radiator; 14) curtain.

Задание 2. Догадайтесь о значении следующих словосочетаний, используемых для описания работы двигателя c водяным охлаждением:

to cool the engine; to circulate water; round cylinders; absorb the heat; over the hot cylinders; to expose surface area; the air flow; the pressurised system; boiling point.

Задание 3. Расскажите об устройстве и работе двигателя с водяным охлаждением, дополнив следующие предложения.

1.In the ... ... engine water ... heat.

2.Water circulates in ... ... round cylinders.

3.The heated water is passed through ... .

4.The radiator ... a very large surface area to the ... ... .

5.The cooled water ... again over the hot ... .

6.… maintains the required temperature of the ... .

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Vocabulary

Узлы и детали двигателя с водяным охлаждением: water jacket, cylinders, radiator, thermostat, engine.

Глаголы, используемые для описания рабочих процессов в двигателе с водяным охлаждением:

to absorb, to expose, to circulate, to cool.

fan belt

Рис. 11

Текст 18

THE THERMOSTAT

The thermostat is a heat operated valve which controls the water flow through the radiator. It is normally located on the engine below the top outlet hose. When the engine is cold the thermostat is closed and it opens gradually аs the engine warms to reach the fully open position when the engine is at normal operating temperature.

When the engine is first started the water in the cylinder block heats up

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quickly because the thermostat prevents it from circulating through the radiator. As the water becomes warm some circulation is allowed but water in the cylinder block is always maintained at a high temperature and it is some time before the whole of the water in the system i.e. at its normal operating temperature.

Failure of the thermostat can cause overheating or over-cooling.

Задание 1. Дополните следующие предложения соответствующими окончаниями из правого столбца:

Задание 2. Расскажите о месте термостата в системе водяного охлаждения по следующему плану:

а) местонахождение; б) назначение; в) принцип работы.

Vocabulary

Детали двигателя: valve, radiator, engine, the top outlet hose, cylinder

block.

Глаголы, используемые при описании работы термостата:

To control, to locate (mount), to close, to open, to warm, to reach, to start, to heat up, to prevent, to circulate.

OVERHEATING

Overheating may be due to a fault in the engine and, in a water cooled engine, overheating accompanied by loss of power water generally indicate a fault somewhere other than in the cooling system, such as weak mixture, retarded ignition, or binding brakes, possibly the handbrake. Overheating due to a fault in the cooling system could be caused simply by a low water level. A common cause is a broken fan belt.

Another cause of overheating is restriction of water flow due to a deposit

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of "fur" in the system, because of the calcium content of the rater being high. The deposit may be effectively removed by using one of the proprietary "fur" removers.

Occasionally the radiator matrix, especially when it faces the direction of travel, becomes clogged with insects and dirt and its effeciency is in consequence reduced.

Задание 3. Переведите словосочетания с определениями, образованными по моделям.

N + N, Ved + N, Ving +N

Water cooled engine; cooling system; retarded ignition; binding brakes; water level; fan belt; water flow; calcium content; "fur" removers; radiator matrix.

Задание 4. Расскажите о причинах перегрева двигателя с водяным охлаждением.

Задание 5. Просмотрите текст и озаглавьте его.

Air cooled engines run at very much higher temperature than water cooled engines do. Air cooled engines heat up more quickly than water cooled engines do and this reduces cylinder wear slightly; it also reduces fuel consumption during the heating — up period. Air cooling also eliminates the need for a radiator and its connecting hoses, thermostat and water cooled engine is the fact that it is very much quieter due to the noise deadening effect of the water jacket round the cylinder.

Задание 6. Найдите русские эквиваленты для следующих английских слов и словосочетаний:

A). To run; to heat up; to reduce; cylinder wear; fuel consumption; to eliminate; to require; noise deadening effect.

B). Потребление топлива; снижать; работать; шумопоглощающий эффект; нагреваться; износ цилиндра; устранять; требовать.

Задание 7. Укажите преимущества и недостатки двигателя с…

a) воздушным охлаждением;

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b) водяным охлаждением.

Задание 8. Просмотрите текст “ Antifreeze” и найдите ответы на вопросы.

1.Как может пострадать двигатель при отсутствии антифриза?

2.Каково соотношение воды и антифриза в системе охлаждения?

3.Какие 2 способа заправки системы охлаждения антифризом Вы

знаете?

ANTI-FREEZE

In the winter time anti-freeze must be used; water alone will freeze in the coldest weather and the result of this is likely to be a cracked block. Long life anti-freeze is now obtainable and it is usual to keep it in the system Summer and Winter.

It is best to flush out the system thoroughly before filling with fresh antifreeze mixture of even if water was previously in the system. A common strength of the mixture is 25%, or one part anti-freeze to three parts water. Antifreeze can be used in two ways. One is to mix the anti-freeze and water in the correct proportions in a large container and fill the system from this. Alternatively, knowing the water capacity of the cooling system, you find out how much anti-freeze is required and pour this into the drained system and then fill up to the correct level with clean water.

Задание 9. Укажите функции инфинитива в тексте “Anti-freeze”.

Текст 19

Задание 1. Слушайте и повторяйте:

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