Английский язык. Писарева Л.П. - 20 стр.

                                     4 курс
                             Контрольная работа № 4

   Грамматический материал, который необходимо повторить студенту прежде,
чем приступить к выполнению упражнений контрольной работы № 4.
- Неличные глагольные формы:
   Причастие (Participle I, Participle II)
   Инфинитив (Infinitive)
   Герундий (Gerund)
- Модальные глаголы (can, must, may, could, might) и их заменители (to be able
   to, to have to, to be allowed to, should, to be to)
- Система времен в английском языке.

Для защиты контрольной работы необходимо:
1. Устно ответить на вопросы к тексту.
2. Кратко пересказать текст контрольной работы.



                                     Вариант I
                                        Text
                                  “Cooling System”

When fuel burns in the cylinders of a diesel engine, only about one-third of the fuel’s
heat energy changes into mechanical energy, and then leaves the engine in the form of
brake horsepower. The rest of the heat shows up in hot exhaust gases, frictional heat of
the rubbing surfaces and heating of the metal walls which form the combustion
chamber, namely, the cylinder head and piston. The cooling system’s job is to remove
the unwanted heat from these parts so as to prevent:
1. Overheating and resulting breakdown of the lubricating-oil film which separates the
   engine rubbing surfaces.
2. Overheating and resulting loss of strength of the metal itself.
3. Excessive stresses in or between the engine parts due to unequal temperatures.
Cooling is usually provided also for the exhaust manifold to prevent its reaching an
uncomfortable temperature. Cylinder heads and cylinders are generally provided with
jackets through which cooling water is circulated. Pistons transfer their heat to the
cylinder walls and to the lubricating oil. Many engines use oil coolers to remove the
heat in the lubricating oil. The heat balance of an engine and the amount of heat
absorbed by the cooling water vary with the type of engine and the design of cylinders,
exhaust manifold, pistons, lubricating-oil system and any other equipment which may
be cooled directly or indirectly by the circulating water.
Closed Cooling Systems
In closed cooling systems the jacket water is recalculated through closed heat
exchangers. A heat exchanger is a device that transfers heat from one fluid to another.
Thus, in closed systems, the same water remains in the system indefinitely and is
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