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:

VEHICLES AIR CONDITIONING AND ENVIRONMENT

1. In the near future, there will be 1 billion vehicles on the world's roads. As this number grows, so does environmental concern over fuel usage, emissions, and end-of-life disposal.

2. Today's vehicles are composed of many systems, each affecting customer satisfaction and environmental impact. One of many such systems is air-conditioning (A/C). Customers have come to expect the high level of comfort and safety current systems offer. As a result, A/C is now standard on most new vehicles in the U.S. while demand for it in Europe and Asia is rising. The refrigerant used in current systems is HFC-134a, which is classified as a global warming gas and is under scrutiny for possible phase-out in Europe. Emissions of HFC-134a from vehicle A/C systems account for about 0.1% of total world emissions. While the automotive industry is improving HFC-134a systems, it is evaluating two replacement refrigerants: carbon dioxide (C0₂) and propane. The C0₂ system has higher operating pressures; if used, C0₂ would require all new A/C system components.

3. The use of propane requires only a modification of the existing HFC-134a system. In the secondary-loop propane system, a device in the engine compartment chills a coolant (water-glycol). This coolant, not propane, circulates through the passenger compartment.

4. Although these technical options are promising, cost-benefit analysis is needed to understand the environmental and consumer benefits they offer compared to other potential vehicle fuel-saving technologies.

5. The international impact of SAE (Society of Automotive Engineers) documents on mobile A/C systems is far-reaching. SAE standards for system design, service equipment, and technician service procedures and training have been used throughout the world. Vehicle makers will have to determine which systems need to be changed to best manage total vehicle emissions and then implement those changes.