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Тексты по направлению
190600.62 "Эксплуатация транспортно-технологических машин и комплексов"
ВАРИАНТ 1
1. Прочитайте и письменно переведите на русский язык текст:
THE DIESEL ENGINE
In 1890s, Rudolf Diesel, a German, invented the engine that bears his name. As distinguished from gasoline engines diesels have no ignition system fed with electricity. The fuel is ignited simply by contact with very hot air in the cylinder. The operation performed is like this: when taken in the cylinder the air is highly compressed, the temperature rises so the heated fuel-air mixture burns. The higher the pressure, the higher is the temperature. Besides the compressed mixture produced more power than that uncompressed. Diesel engines power many of the used vehicles and other equipment. They are usually used in cases where engine weight is not a prime factor. Their advantage is that they are simple in design and use much heavier liquid fuels than gasoline engines. The cost of a heavier fuel is much less than that of a light one. Besides the fuel consumption of a diesel is much less than that of gasoline engines. Although applied for many purposes diesel engines have certain disadvantages. Their weight is more than that of a gasoline engine of the same power and it occupies much space. The disadvantages of diesels as passenger-car engines are slow performance, noise and smoke. All the companies investigating diesels are trying to reduce noise and smoke, but the problems are not yet entirely solved. Diesel engines clatter when started on a cold morning. And the warm-up period for all diesels seems too long to drivers accustomed to gasoline models.
2. Прочитайте текст снова и письменно ответьте на вопросы:
1. Who invented the diesel engine?
2. Do diesel engines have ignition system fed with electricity?
3. How is the fuel ignited in the diesel engine?
4. What is the operation performed?
5. What is the advantage of diesel engines?
ВАРИАНТ 2
1. Прочитайте и письменно переведите на русский язык текст:
THE ENGINE
The word engine originally meant any ingenious device, and came from the Greek word ingenious, clever. Any kind of vehicle must be able to move. The ability to move demands power. A machine that produces mechanical power or energy is called an engine or a power plant. Engines present one of the most interesting groups of problems considered in the engineering field. One of the main problems is receiving the maximum possible power or thrust for minimum weight. The weight is included in the factor called the weight/power ratio, which may be defined as the weight in pounds per horse power output. Another important problem is that of fuel. Both in the past and today the designers work to lower specific fuel consumption. Specific fuel consumption is obtained by dividing the weight of the fuel burned per hour by the horse power developed. Another possible problem considered in any engine is its flexibility. Flexibility is the ability of the engine to run smoothly and perform properly at all speeds and through all variations of atmospheric conditions. One more important problem worked at by the designers is the engine reliability. The engine is to have a long life, with maximum of time between overhaul periods. In some cases the problem of balance is one of the main. Balance has several possible meanings but the principle factor is freedom from vibration. Besides any engine must be started easily and carry its full load in a few minutes. There are gasoline engines, diesel engines, gas turbines, steam engines, jet engines and rocket engines. Each of them has certain advantages and disadvantages over other forms of power plants.
2. Прочитайте текст снова и письменно ответьте на вопросы:
1. What did the word engine originally mean?
2. What is one of the main problems engines present?
3. What is flexibility of the engine?
4. Do the designers work at the engine reliability?
5. What engines do you know?
ВАРИАНТ 3
1. Прочитайте и письменно переведите на русский язык текст:
THE ENGINE
Basically, the automobile consists of three parts: the power plant, or the engine, the chassis and the body. To these may be added the accessories: the heater, lights, radio, speedometer and other devices. The engine is the source of power that makes the wheels rotate and the car move. It includes electric, fuel, cooling and lubricating systems. It is usually called an internal combustion engine because gasoline is burned within its cylinders or combustion chambers. Most automobile engines have six or eight cylinders. The operating cycle of the four-stroke engine that takes place in the engine cylinder can be divided into four strokes. The upper limit of the piston movement is called the top dead centre. The lower limit of piston movement is called the bottom dead centre. A stroke is the piston movement from the top dead centre to the bottom dead centre, or from the bottom dead centre to the top dead centre. In other words, the piston completes a stroke each time it changes the direction of its motion. Where the entire cycle of events in the cylinder requires four strokes (two crankshaft revolutions), the engine is called a four-stroke cycle engine. The four strokes are: intake, compression, power and exhaust. Two-cycle engines have also been made, and in such engines the entire cycle of events is completed in two strokes or one revolution of the crankshaft. On the intake stroke the intake valve is opened. The mixture of air and vaporized gasoline is delivered into the cylinder through the inlet valve. On the compression stroke the inlet valve is closed so that the mixture can be compressed.
2. Прочитайте текст снова и письменно ответьте на вопросы:
1. What parts does the automobile consist of?
2. What is the engine?
3. How many cylinders do most automobile engines have?
4. How is the upper limit of the piston movement called?
5. How is the lower limit of piston movement called?
ВАРИАНТ 4
1. Прочитайте и письменно переведите на русский язык текст: