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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 СибАДИ56 части 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 between heat transfer and heat dissipation.

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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 СибАДИ57 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 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 сло-

восочетаниями: 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.

Задан е 8. Оп ш те устройство работу двигателя с воздушным охлажден ем по р сунку (fig.11).

Fig.11. Air-cooling system

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При описании используйте уже известные Вам модели:

СибАДИ59 Глаголы глагольные сочетания, используемые для описания процесса охлажден я двигателя: to cool, to pass over, to blow through, to mount, to drive, to control, to force air through.

Задан е 9. Законч те 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 данных: cool, melt, heat, use, conduct, regulate, convert, radiator, possibility.

Задание 11. Найдите ответ, соответствующий содержанию текста.

1.What is the function of the cooling system in an automobile engine? 2.What type of engine cooling system can be found in modern vehi-

cles?

3.How much heat is created during the automobile operation? 4.What is the function of the water jacket?

Текст 17 WATER-COOLED ENGINES

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.

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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 “pressurized”. The filler cap

Сhas a spring loaded valve in it to maintain the pressure in the radiator about

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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 al-

дениемlows air into the system as the water cools and thus avoids the formation of a partial vacuum.

Задан е 1. Изуч те р сунок (fig. 11) и подберите русские эквиваленты терм нов, о означающих элементы двигателя с водяным охлаж-

sensor; 12) cylinder;б13) oil radiator; 14) curtain.

. Проверьте се я 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)

system; boiling point. А

Задание 2. Догадайтесь о значении следующих словосочетаний, используемых для описания ра оты 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

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

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.

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